Logotyp: till Uppsala universitets webbplats

uu.sePublikationer från Uppsala universitet
Ändra sökning
Avgränsa sökresultatet
12 1 - 50 av 65
RefereraExporteraLänk till träfflistan
Permanent länk
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association
  • vancouver
  • Annat format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annat språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf
Träffar per sida
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sortering
  • Standard (Relevans)
  • Författare A-Ö
  • Författare Ö-A
  • Titel A-Ö
  • Titel Ö-A
  • Publikationstyp A-Ö
  • Publikationstyp Ö-A
  • Äldst först
  • Nyast först
  • Skapad (Äldst först)
  • Skapad (Nyast först)
  • Senast uppdaterad (Äldst först)
  • Senast uppdaterad (Nyast först)
  • Disputationsdatum (tidigaste först)
  • Disputationsdatum (senaste först)
  • Standard (Relevans)
  • Författare A-Ö
  • Författare Ö-A
  • Titel A-Ö
  • Titel Ö-A
  • Publikationstyp A-Ö
  • Publikationstyp Ö-A
  • Äldst först
  • Nyast först
  • Skapad (Äldst först)
  • Skapad (Nyast först)
  • Senast uppdaterad (Äldst först)
  • Senast uppdaterad (Nyast först)
  • Disputationsdatum (tidigaste först)
  • Disputationsdatum (senaste först)
Markera
Maxantalet träffar du kan exportera från sökgränssnittet är 250. Vid större uttag använd dig av utsökningar.
  • 1.
    Abdelki, Andreas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för materialvetenskap, Nanoteknologi och funktionella material.
    Fused deposition modeling of API-loaded mesoporous magnesium carbonate2020Självständigt arbete på avancerad nivå (yrkesexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    In this thesis, the incorporation of drug loaded mesoporous magnesium carbonate as an excipient for the additive manufacturing of oral tablets by fused deposition modeling was investigated. Cinnarizine, a BCS class II drug, was loaded into the pores of the mesoporous material via a soaking method, corresponding to a drug loading of 8.68 wt%. DSC measurements on the loaded material suggested that the drug was partially crystallized after incorporation, meanwhile the XRD diffractogram implied that the drug was in a state lacking long range order. The drug loaded material was combined with two pharmaceutical polymers, Aquasolve LG and Klucel ELF, and extruded into filaments with a single screw extruder. Filaments of Klucel ELF and drug loaded Upsalite (30:70 wt% ratio) were successfully implemented for the printing oral tablets, in contrast to the Aquasolve LG based filaments which were difficult to print due to thickness variations and non-uniform material distributions. The drug content obtained by TGA suggested drug loadings of 7.71 wt% and 2.23 wt% in the drug loaded Upsalite and tablets respectively. Dissolution studies using an USP II apparatus showed a slower API-release from the tablets in comparison to the crystalline drug, most probably due to slow diffusion of drug species through the polymeric matrix. For future studies, pharmaceutical polymers with higher aqueous solubility should be investigated in order to thoroughly examine the potential of utilizing the immediate release property of Upsalite.

    Ladda ner fulltext (pdf)
    fulltext
  • 2.
    Abenayake, Himesha
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för materialvetenskap, Tillämpad materialvetenskap. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Oorganisk kemi.
    Additively Manufactured Rare Earth Free Permanent Magnets2023Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    It’s well known that MnAl(C) material consists of a metastable phase (τ) with promising ferromagnetic properties, produced either by controlled cooling from the high-temperature hexagonal ε-phase or rapid cooling that freezes the ε-phase followed by low-temperature annealing. Due to the high cooling rates involved, additive manufacturing (AM) especially selective laser melting (SLM), has been identified as a possible method to retain the high-temperature ε-phase, hence containing a potential capacity to produce permanent magnets upon low-temperature annealing. Moreover, the competency of additive manufacturing to address manufacturing design complexity, material scarcity and tailored properties, yields a great opportunity to produce permanent magnets with suitable magnetic properties for complex applications. This work provides a systematic study on three main aspects; development of printing parameters for improved relative density of as-printed MnAl(C) samples; investigation of the influence of scanning strategies on the crystallographic texture of as-printed and annealed samples; investigation of the influence of annealing time and temperature on τ-phase purity and magnetic properties. It was found that laser remelting (multiple laser exposure) combined with specific scanning strategies is a promising path to enhance the relative density of as-printed samples. Some specific scanning strategies were found to be capable of retaining relatively strong crystallographic textured ε-phase in as-printed samples. Following the annealing process for ε→τ transformation, only a partial transformation of crystallographic texture was observed. Characterization of annealed samples through XRD (x-ray diffraction) and phase fractions calculations through Rietveld refinement reveals that relatively short annealing times and low temperatures result in incomplete ε→τ transformation. In addition, longer annealing times and higher temperatures surpass the complete ε→τ transformation and lead to the formation of equilibrium phases subsequently reducing the magnetic performance. Furthermore, the experimental findings demonstrated a pronounced influence of higher carbon content in the powder, resulting in improved magnetic properties.

    Ladda ner fulltext (pdf)
    Additively Manufactured Rare Earth Free Permanent Magnets
  • 3.
    Amaralapudi Bala Vardha Raju, Rahul
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för materialvetenskap.
    Thammisetty, Raja Surya Mahesh
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för materialvetenskap.
    Material selection and topology optimization of a shift fork for metal 3D printing2022Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    In collaboration with Kongsberg Automotive, the thesis focuses on material selection and redesigning the shift fork for additive manufacturing using topology optimization. The shift fork is a component in the gear shifting mechanism in the automotive industry. The current shift fork at Kongsberg is manufactured from aluminum using die-casting. This design and material do not withstand huge dynamic loads in commercial vehicles. The material to withstand the loading conditions and is widely available across powder manufacturers is selected using the weighted properties method. The topology optimization of the design resulted in a 50 % reduction in mass. The shift fork's two legs undergo uneven load distribution due to eccentricity. The optimized models are simulated using Finite Element Analysis to validate the design. The optimized design is obtained such that the difference in displacement between both legs is within 50 %. Numerous metal powder manufacturers and 3D printing service providers were contacted to understand the current additive manufacturing market.

    Ladda ner fulltext (pdf)
    fulltext
  • 4.
    Berglund, Johan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Industriell teknik.
    Framtagning av ny bärare för kassettöverdelar2015Självständigt arbete på grundnivå (yrkesexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Fiomi Diagnostics AB tillverkar och utvecklar patientnära blodprovskassetter för attidentifiera risk för hjärtinfarkt och hjärtsvikt för att användas inom hälsovården.Kassetterna består av tre huvuddelar, en överdel, en underdel samt ett plastchip.Underdelarna kommer direkt från leverantör till monteringen medan överdelarna måsteförses med ett blodseparationsmembran genom ultraljudssvets innan det kan skickas tillmonteringen.

    I dagsläget förses överdelarna med blodseparationsmembran på våningen undermonteringen och måste därför transporteras på bärare till monteringen. Dessa bärare äridag stora plåtar (400 x 600 mm) som rymmer 120 kassettöverdelar, men som ärskrymmande både vid ultraljudsprocessen och vid monteringen. För att lösa platsbristenställer operatörerna dessa plåtar ofta snett bakom sig där plats finns. Detta skaparergonomiska problem då många vridningar av överkroppen sker vid båda processerna.

    För att lösa de ergonomiska problemen initierades detta examensarbete för att ta fram enny smidigare bärare mellan processerna. I arbetet så används TRIZ för att genererakreativa koncept samt sålla bland dessa och kombinera det som var bra från ett koncepttill andra. Efter konceptfasen utforskades olika produktionstekniker för att tillverkakoncepten. För att veta att koncepten kunde tillverkas för tänkt tillverkningsmetodkontaktades tillverkare och tillfrågades vad som krävdes för att metoden skulle varagenomförbar. Tillverkningsmetoder som utforskades var; formsprutning, extrusion avplast samt aluminium, vakuumformning, additiv tillverkning samt plåtbockning.

    Prototyper togs fram med hjälp av 3D-printer av de tre bästa alternativen för att utvärderasav operatörerna som i framtiden kan komma att använda dessa. Tillsamman med enutvärdering av bärarnas ekonomi och prestanda utsågs en rekommendation av vilkenbärare som bör användas.

    Resultatet blev en bärare tillverkad genom plåtbockning med utskuret mönster för att låtakassettöverdelarna hänga i den. Designen har en kapacitet för 60 kassettöverdelar vilketär en halvering av den befintliga, men basytan för den nya designen är en sjättedel av denbefintliga bäraren vilket ger en yteffektivitetsökning med 300 %. Då seriestorleken avbärarna var relativt låg så blev plåtalternativet också billigaste av alternativet.

    Ladda ner fulltext (pdf)
    fulltext
  • 5.
    Bergman, Henrik Dan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Increasing the Writing Resolution for Electro-hydrodynamic 3D-Printing: by Active Steering of e-jet2019Självständigt arbete på avancerad nivå (yrkesexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Additive manufacturing has grown considerably during the last couple of decades, whether it comes to the printing of metal structure or living cells. Additive manufacturing techniques relays on the successive addition of material to create the wanted structure. Among the diversity of these many printing techniques, electrohydrodynamic 3D-printing is of particular interest, as the technique has a promising outlook for high-resolution printing on the microscale. The technique is compatible with a myriad of thermoplastics, but its writing resolution is limited due to the inherent affect the manufacturing process has on the material. Electrostatic forces between already deposited fibres and the fibre in light affect the final position of printed fibre. This thesis evaluates the possibility to increase the writing resolution in melt electrohydrodynamic 3D printing by a closed-loop feedback system. Components were built and added to an already existing printing setup to implement in-situ measurements of the fibres position as well as active electrostatic guiding of the fibre. The setup consisted of a camera that determined the position of the fibre; the position was then used in a PID controller to calculate an appropriate potential. The potential was forwarded to a high voltage amplifier, connected to a steering electrode, mounted in the vicinity of the jet. The setup built for one-dimensional steering of the fibre improved the printing accuracy by ten times through suppressing the repulsive/attractive forces, where the process variable of the PID controller was measured. However, the precision decreased roughly four times as it was deposited on the substrate. The limitations of the system have been evaluated, and possible improvements for the two-dimensional control of the fibre are further discussed.

    Ladda ner fulltext (pdf)
    fulltext
  • 6.
    Bjelke, Carl-Johan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för samhällsbyggnad och industriell teknik, Industriell teknik.
    Additive Manufacturing for Volume Production: A case study in supply chain benefits of AM implementation2023Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Additive manufacturing was first introduced in the 80s and has ever since been used as a tool for rapid prototyping. Its flexible manufacturing characteristics makes it optimal for creating complex geometries in one manufacturing process, eliminating assembly time for several individual parts. Additive manufacturing has yet not been introduced as a tool for volume manufacturing. This has historically been because of quality concerns in printing as well as printing speed. Recent technique developments mitigated these issues and the case for additive manufacturing in volume production is revaluated in a context of supply chain benefits in this study. 

    The primary data was collected using interviews at the case company. Additionally official company document was used as empirical data, in conjunction with a scientific literature review to achieve data triangulation.  The results were then analyzed using a system dynamics approach. Finally, a conceptual solution of a present-day supply chain setup with additive manufacturing integration is presented.

    The analysis resulted in a solution where additive manufacturing capabilities were integrated at or near the location of the outsourced production and assembly services. This can act as a production buffer to mitigate issues related to variability in shipping. This technique can be implemented without significant alterations to the present supply chain practices. However, in order to reap the full benefits, i.e., gaining flexibility in production as greater design freedom, of using additive manufacturing, the design process must be adapted for the additive manufacturing technique. 

    Ladda ner fulltext (pdf)
    fulltext
  • 7.
    Borg, Mikael
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för materialvetenskap.
    Automatization of de-powdering process for binder jetting technology2022Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Additive manufacturing has gained considerable attention in recent years due to its capabilities of producing complex parts with tailormade mechanical properties. Because of its infancy state, additive manufacturing production chains are seldom optimized to the same extent as conventional manufacturing techniques. Companies with additive manufacturing production sitesusing powder as a building material often find themselves devoting a lot of resources towards depowdering, a post processing step that has potential of being a significant bottleneck.The purpose of this master thesis was to develop a de-powdering system that would function automatically, relieving operators from performing the process step manually. The following work has been conducted at Sandvik in Sandviken at the department for additive manufacturing.Results were acquired with high credibility due to a mixture of qualitative and quantitative gathering techniques that supplemented each other. Together with a literature review, empirical data gave rise to the possibility of developing a new de-powdering system for binder jetting technology.Optimization of the system indicated that larger inlets produced a higher removal efficiency. This was later confirmed with computational fluid dynamics, where smaller nozzles created a more turbulent air flow, making it difficult for powder particles to exit the system. Though final trials with green bodies revealed that the system, in its current state, did not have the capabilities of replacing manual de-powdering completely, it certainly displayed how efficient it can be with further development. 

    Ladda ner fulltext (pdf)
    fulltext
  • 8.
    Bremler, Oskar
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för materialvetenskap, Tillämpad materialvetenskap.
    Fatigue and microstructural study of a 316L austenitic stainless steel marine component produced by Wire Arc Additive Manufacturing (WAAM)2022Självständigt arbete på avancerad nivå (yrkesexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    In this study, the fatigue- and fracture properties and microstructure of a marine component of austenitic stainless steel 316L manufactured with the novel method Wire Arc Additive Manufacturing were investigated and compared with data from literature. The purpose was to find a critical flaw size in the material related to its fatigue life.

    It was done by studying the microstructure and interpreting fatigue- and mechanical data for the marine component in empirical models related to the fatigue- and fracture properties. Fracture properties were approximated to estimate fatigue life and critical flaw size. Fatigue limit and fatigue threshold were based on hardness test data, fracture toughness, and FADs on Charpy-V impact test data.

    The material manufactured with Wire Arc Additive Manufacturing had superior fatigue properties than cast and rolled equivalents and performed better in the fatigue test than recommendations for austenitic stainless steel in a seawater environment from the British Standard 7910:2019. Due to the conservative model's fatigue limit and fatigue threshold, the results are conservative. The reason for that could be the crack closure properties of the material. The results for fracture toughness are lower than the literature data. This is most likely due to conservative models based on Charpy-V impact test data.

    The most important properties of the fatigue life are the fatigue limit and the fatigue threshold due to their relationship with crack growth. Testing the lifetime of the component in seawater is complex and time-consuming due to the corrosion and the need for low test frequency.

    Ladda ner fulltext (pdf)
    fulltext
  • 9.
    Bugurcu, Alan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för materialvetenskap, Mikrosystemteknik, Ångström Space Technology Centre (ÅSTC).
    Investigation on how additive manufacturing with post-processing can be used to realize micronozzles2022Självständigt arbete på avancerad nivå (yrkesexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    This is predominantly a qualitative study on the manufacturing of micronozzles with an additive manufacturing (AM) technique, namely the laser-powered powder bed fusion (PBF-LB). 

    Manufacturing of micronozzles with standard microelectromechanical system technology often results in 2.5-D or close to 3-D structures and does not yield a fully rotationally symmetric nozzle. For this reason, AM can be a better solution. However, the structures obtained with PBF-LB exhibit very rough surfaces which will impair the performance of the micronozzle. To improve the surface finish electropolishing was performed on the interior walls. 

    Given the shape and the scale of the components, uniformity of the polishing is a challenge, calling for an inventive electrode configuration and electrolyte feed solution. The approach was to integrate an electrode on the inside of the converging part of the nozzle, to serve as a cathode for the electropolishing, already in the process, and to make the nozzle itself the vital part of the fluidic system. 

    With this, titanium micronozzles were manufactured with throat diameters varying between 300 and 800 μm. With the resolution of the used AM technique, it was possible to integrate the internal electrode in the micronozzles with a designed throat diameter down to 600 μm. Below this, the anode, and cathode, sometimes made contact short-circuiting the cell. Profilometry showed a decrease of the average surface roughness (𝑅𝑅𝑎𝑎) with 15-60 % for the electropolished micronozzles. The Schlieren imaging showed an exhaust that followed the throat’s axial direction and also demonstrated pressure disks and, hence, a supersonic jet exhaust. This study has shown that AM is a viable choice for manufacturing of rotationally symmetric micronozzles, and that electropolishing could be used to decrease the surface roughness on their inside uniformly with the integration of a cathode. 

    Ladda ner fulltext (pdf)
    fulltext
  • 10.
    Bång, Oskar
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Industriell teknik.
    Additiv teknik, ett hjälpmedel i produktutvecklingen2016Självständigt arbete på grundnivå (yrkesexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    This bachelor thesis has been carried out in collaboration with Maximatecc AB. In their office in Alfta they work with product development of both hardware andsoftware for various kinds of products including display computers and controllers for different kinds of equipment. In the product development process its common that several different kinds of additive manufactured (3D-printed) prototypes are ordered from an external company.

    The main objective with this thesis is to increase the knowledge about different kinds of additive manufacturing technologies that exists and are relevant for the company and how and why prototypes are important for the product development process. It will also with the help of interviews and observations at the company investigate how additive technologies are used today at Maximatecc and what other needs of the technology that exists. By doing so it will be determined if there is a need to buy an3D-printer or continue to order the service from an external company. A practical part of this thesis is to see if a component manufactured with different kinds of additive technologies is suitable to work as a substitute to an injection molded part in a product during the prototype phase.

    There could be a need for to buy a 3D-printer that uses FDM (fused depositionmodelling) -technology but it will not replace the need to buy in additive manufactured prototypes from an external company. This is because of the different kinds of desired attributes of the prototypes used during the product development process and the advantages and disadvantages of the different kinds of technologies.

    It was also concluded that components manufactured with additive technology could be used as a part in a functional product during the prototype phase. This could be used to send fully working prototypes to customers early in the product development process.

    Ladda ner fulltext (pdf)
    fulltext
  • 11.
    Cannataro, Loris
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för samhällsbyggnad och industriell teknik, Industriell teknik.
    Understanding Proximity in Research Consortia: A case study of proximity dimensions within the AddLife Competence Centre2020Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Today’s knowledge creation process has become extremely complex. On the one hand, technological innovation increasingly requires the use of complementary expertise from several apparently unrelated fields. On the other, the magnitude of the challenges that research and development present often require a large amount of resources that single actors can hardly achieve by themselves. For these reasons, the popularity of collaborative research has increased greatly in recent years. Among the many forms of collaborative research adopted today, research consortia are the most used.

    Given the steady increase of this trend, it has become important to understand the dynamics at play in research consortia. In particular, it is crucial to understand how participants interact with each other and the implication of such interactions on the success of a consortium’s outcome. The following study utilises a proximity-based framework to the single case study of the AddLife Competence Centre, an Uppsala University based R&D consortium for the development of Additive Manufacturing technology applied to Life Science. The data was collected by conducting eleven semi-structured interviews of AddLife participants.

    This study begins by presenting an overview of the literature on collaborative network, collaborative research and proximity. It moves onto analysing the interactions of actors in AddLife as a triple helix arrangement. Next, linkages between actors are expressed in terms of organisational, cognitive and social proximity. The analysis is discussed and presented as follows: uncertainty and discrepancies can lower organisational proximity, while the lack of goals alignment can lower cognitive proximity. High social proximity can mitigate the effects of both, especially in case of opportunistic behaviour. Acting on these three proximity dimensions should be prioritised over other proximity trade-offs.

    Ladda ner fulltext (pdf)
    fulltext
  • 12.
    Daly, Colin
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för materialvetenskap, Tillämpad materialvetenskap.
    Increased build rate by laser powder bed fusion of SSAB steel powder2023Självständigt arbete på avancerad nivå (yrkesexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    SSAB has built a pilot gas atomization facility looking to expand their expertise of steel into the metal powder and additive manufacturing industry. Laser powder bed fusion is an additive manufacturing method that melts and fuse metal feedstock powder together layer by layer using a high intensity laser. The complex process requires optimization in order to be competitive. The process parameters laser power, scan speed, hatch distance and layer thickness largely govern the build rate and total production time. To increase the build rate, two iterations of test cubes with unique parameters sets were experimentally printed. Evaluation of relative density, porosity, microstructure, hardness and mechanical properties was performed. All results were compared to a reference parameter set previously studied. A candidate parameter set successfully increased the build rate by 116% while maintaining satisfactory material properties.

    Ladda ner fulltext (pdf)
    Exjobb SSAB FINAL
  • 13.
    Deepankar Reddy, Attivarapu
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för samhällsbyggnad och industriell teknik, Industriell teknik.
    Bhat, Hemanth Ramesh
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för samhällsbyggnad och industriell teknik, Industriell teknik.
    Determining the factors influencing In-House Implementation of Additive Manufacturing versus External Supplier Reliance in the Surgical Field: Quantitative Research2023Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Additive manufacturing (AM), also known as 3D printing, has arisen as a revolutionary technology with the potential to revolutionize numerous industries, including the medical industry. It is a layer-by-layer manufacturing process used to create intricate structures. Numerous industries are planning to implement it on a large scale in order to meet the bespoke market demands as a result of its ability to produce individualized components. This study investigates the determinants influencing the adoption of AM in-house versus reliance on external suppliers for applications involving additive manufacturing.

    The study acknowledges the significant impact that AM has had on the evolution of the medical field, allowing for customized medical devices, patient-specific implants, and sophisticated surgical instruments. The purpose of this study is to determine the factors influencing the adoption of AM in-house versus reliance on external suppliers for applications involving additive manufacturing. This study utilized a quantitative approach with a survey-based methodology. The sample population consisted of university hospital surgeons from various origins. This research aims to gain insight into their preferences, motivations, and concerns when it comes to implementing AM by analysing their perspectives. The study employs the Consolidated Framework for Implementation Research (CFIR) framework to analyse the findings. This theoretical framework offers a comprehensive lens through which to analyse the factors that influence the adoption of AM in the medical setting. Utilizing the CFIR framework, this study investigates the numerous factors that influence the perceptions and decision-making processes of surgeons.

    In conclusion, this research examines the determinants influencing the adoption of AM in-house versus reliance on external suppliers for applications involving additive manufacturing. The quantitative approach, coupled with the application of the CFIR framework, enables a thorough examination of the factors that influence the decision-making processes of surgeons. This study's findings have implications for the future implementation and utilization of AM in the medical field, thereby contributing to the advancement of patient care and surgical procedures.

    Ladda ner fulltext (pdf)
    Additive Manufacturing implementation in medical care
  • 14.
    Deole, Dhruva
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för materialvetenskap, Nanoteknologi och funktionella material.
    3D Printing of Magnesium- and Manganese-Based Metal-Organic Frameworks for Gas Separation Applications2022Studentarbete övrigt, 10 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Metal Organic Frameworks (MOFs) are a class of porous materials that are predominantly obtained as powders and have been investigated as a solid sorbent for gas separation or carbon capture applications from combustion exhaust gases. The manufacturing of products with MOFs to use them for real life applications is still a major problem. The most common productization method used is to form pellets of the powder MOFs. This has a limitation on the product shape which makes it difficult for it to be used in gas separation applications. This study focuses on using additive manufacturing technique to give MOFs a lattice (mesh-like) geometry which is useful for gas separation applications as the mixture of gases would be able to pass through the lattice structure and be separated due to the inherent MOF properties and characteristics. Two MOFs based on magnesium and manganese salts have been studied in this project. An extrudable paste developed using alginate gel as a binder with these MOFs. With alterations in paste formulations and 3D printer parameters, lattice structures were printed using the two MOFs. CO2 and N2 gas uptakes were measured showing that the structure adsorbs CO2 gas to a higher extend which results in the separation of N2 gas in both materials. When compared to their pristine powder form, other properties of the MOFs such as crystallinity, microstructure, reusability and surface area remain to be preserved after being 3D printed in both cases. 

    Ladda ner fulltext (pdf)
    fulltext
  • 15. Deshmukh, Kaustubh
    Exploratory study on Additive Manufacturing in Urban mobility2023Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    This thesis report presents a comprehensive study on the design and development of an Additively manufactured Unit cell for car door panels, aiming to enhance impact resistance and reduce noise transmission to the vehicle cabin. In order to accomplish these goals, the study focuses on combining two novel techniques namely quasi-zero stiffness (QZS) structures and phononic crystals (both scattering and locally resonating type).The research begins by looking into similar research work, choosing appropriate unit cell topologies, and characterizing the materials suitable for AM. The performance of the unit cell design is then assessed using FEA simulations. To improve noise absorption and impact resistance, optimization techniques can be used.The experimental results demonstrate that the combination of QZS structures effectively enhances the unit cell’s ability to withstand impacts by redistributing and dissipating energy. Additionally, phononic crystal integration that employs both scattering and locally resonating mechanisms proves successful in attenuating noise transmission across a wide frequency range.The projected performance advantages of the 3D printed unit cell prototypes are confirmed by experimental testing. Measurements of noise absorption, impact resistance and mechanical testing confirm the viability of the suggested design.The findings of this research contribute to the advancement of additive manufacturing techniques in the automotive industry. The proposed unit cell design for 3D printing exhibits potential for enhancing occupant safety and acoustic comfort in automotive door panels. The proposed technologies have the potential to be further optimized and integrated to produce enhanced automotive door panels with higher impact resistance and noise reduction capabilities

    Ladda ner fulltext (pdf)
    fulltext
  • 16.
    Dsouza, Erol Christopher
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för samhällsbyggnad och industriell teknik.
    Hardi, Yash Rajesh
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för samhällsbyggnad och industriell teknik.
    Factors Affecting the Implementation of Additive Manufacturing Technology in Healthcare.2021Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Additive manufacturing (AM) has made it possible for patients to have personalized healthcare treatment such as implants, surgical guides etc., which was not possible previously. Despite the massive opportunity of custom-made implants, some factors made their use in clinical practice more difficult. Keeping this in focus the purpose of our thesis is i) To identify stakeholders relevant to AM in healthcare ii) Identify barriers for AM in healthcare iii) Propose a business framework based on barriers and stakeholder identification. 

    A literature review delineated current barriers for AM in general as well as specific to healthcare. Additionally, different dimensions that AM impacts in healthcare and the current business frameworks used were explored. A case study design was applied using deductive reasoning. The Data was collected from semi-structured interviews with the help of snowball purposive sampling. Also, a part of the studies relied on archival data. CFIR framework was employed for data collection, and an interview guide was prepared using the same. The stakeholder analysis model and new business concepts were also utilized under the theoretical framework. Data from the interview was analysed by thematic analysis. The main themes were the Inner setting, Intervention characteristics, Network, Individual professional characteristics, and Outer setting.

     

    The study results are categorized based on the technology used for printing, i.e., Metal printing and Polymer printing. Metal printing superseded polymer printing in terms of the number of barriers. Moreover, in terms of the ‘Inner setting,’ common barriers for both printing technologies were lack of training for medical professionals w.r.t AM machines and lack of skilled personal for handling the design software. In terms of ‘Intervention characteristics’, lack of infrastructure (not good enough scanner for scanning patients) and lack of user-friendly software were few common barriers for both printing technologies. The theme ‘Individual professional characteristics’ contained barriers like lack of entrepreneurial mindset (lacking in individuals who take initiatives and invest time), laggard’s attitude (individuals not willing to change the way they work), technological barrier due to generation gap, and lack of practical experience. Lack of demand and lack of legal framework were barriers for metal printing in the context of the ‘Outer setting’.

     Lastly, with evidence of AM facing numerous barriers, it becomes paramount to examine those barriers at different levels critically during its implementation. Addressing and tackling them with a solution regarding business frameworks and knowledge of relevant stakeholders can alleviate some of the hurdles.   

    Ladda ner fulltext (pdf)
    fulltext
  • 17. EBI, NIKHIL JOSEPH
    Methodology for evaluation of long-term mechanical properties of viscoelastic materials2023Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Additive manufacturing (AM) enables the fabrication of complex geometries using layer-by-layerdeposition of materials like polymers and metals. However, predicting the long-term viscoelasticcharacteristics of AM polymer parts is challenging due to limited available data. This thesisinvestigates the applicability of time-temperature superposition (TTS) to forecast mechanicalbehaviour over extended timescales beyond experimentally feasible testing durations.Comprehensive stress relaxation testing was systematically conducted on 3D-printed polylacticacid (PLA) samples across a temperature range of 26°C to 34°C using a customised climatechamber. The results demonstrated an increasing rate and extent of stress relaxation at highertemperatures, confirming the viscoelasticity of the printed PLA. Leveraging Python programmingand the Williams-Landel-Ferry (WLF) equation, the individual stress relaxation curves at differenttemperatures were shifted to create master curves. By quantitatively determining the shift factors,a continuous prediction of viscoelastic properties spanning much longer time durations wasachieved. Experimental validation through prolonged relaxation testing showed reasonableagreement between the actual mechanical data and the model predictions, thereby validating thecapability of TTS in expanding the behavioural forecast. This research provides a robustframework and methodology for the accelerated determination of time-dependent viscoelasticcharacteristics of polymers fabricated through additive manufacturing. The computational toolsand experimental techniques established here can be extended to other AM materials likecomposites and metal alloys. Overall, this thesis demonstrates a methodology for timetemperaturesuperposition as a viable and powerful tool for developing comprehensive predictivemodels of the long-term mechanical performance of viscoelastic material.

    Ladda ner fulltext (pdf)
    fulltext
  • 18.
    Eriksson, Philip
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad materialvetenskap.
    Evaluation of mechanical and microstructural properties for laser powder-bed fusion 316L2018Självständigt arbete på avancerad nivå (yrkesexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    This thesis work was done to get a fundamental knowledge of the mechanical and microstructural properties of 316L stainless steel fabricated with the additive manufacturing technique, laser powder-bed fusion (L-PBF). The aims of the thesis were to study the mechanical and microstructural properties in two different building orientations for samples built in two different machines, and to summarize mechanical data from previous research on additive manufactured 316L.

    Additive manufacturing (AM) or 3D-printing, is a manufacturing technique that in recent years has been adopted by the industry due to the complexity of parts that can be built and the wide range of materials that can be used. This have made it important to understand the behaviour and properties of the material, since the material differs from conventionally produced material. This also adds to 316L, which is an austenitic stainless steel used in corrosive environments.

    To study the effect of the building orientation, samples of 316L were built in different orientations on the build plate. The density and amount of pores were also measured. Tensile testing and Charpy-V testing were made at room temperature. Vickers hardness was also measured. Microstructure and fracture surfaces were examined using light optical microscope (LOM) and scanning electron microscope (SEM).

    The microstructure of the 316L made with L-PBF was found to have meltpools with coarser grains inside them, sometime spanning over several meltpools. Inside these coarser grains was a finer cellular/columnar sub-grain structure. The tensile properties were found to be anisotropic with higher strength values in the orientation perpendicular to the building direction. Also high dense samples had higher tensile properties than low dense samples. The impact toughness was found to be influenced negatively by high porosity. Hardness was similar in different orientations, but lower for less dense samples. Defects due to lack of fusing of particles were found on both the microstructure sample surfaces and fracture surfaces. The values from this study compare well with previous reported research findings.

    Ladda ner fulltext (pdf)
    fulltext
  • 19.
    Erol, Burak
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för samhällsbyggnad och industriell teknik, Industriell teknik.
    Datar, Maitreya Chandrashekhar
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för samhällsbyggnad och industriell teknik, Industriell teknik.
    Adoption of Additive Manufacturing in the Food Industry: Exploring marketing, sales, and after-sales strategies for the adoption of Additive Manufacturing in the food industry.2022Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Additive Manufacturing (AM) is a technology that enables to print three dimensional solid objects which can be metal, plastic, and similar. AM has a lot of advantages such as lead time reduction and reduction in the number of steps required for manufacturing compared to the traditional manufacturing (TM) method. 

     

    This research is focused on adoption of AM in the food manufacturing industry. The use of AM in the food industry currently seems to be low. Therefore, the main aim of the research is to understand adoption of AM through marketing, sales, and after-sales strategies, which can be best suited for introduction and saturation of AM products and applications in the food industry. 

    The primary data is gathered from the potential customers (experts from the food industry), sales personnel who sell products and machinery in the food industry and the employees of the sponsor company, and it consists of thirteen different interviews. Qualitative interviews were conducted to obtain an in-depth knowledge about the perceptions and perspectives of AM in the food industry.

    AM has the potential to be adopted as the main manufacturing method for spare parts in the food industry. But, considering the market today, the potential of adoption seems to be wasted. Three different analyses help in determining the current situation of the AM industry and help to understand the potential that AM brings to the food industry.

    Outcomes of the qualitative interviews present the researchers with in-depth knowledge of facilitators and barriers that AM companies may face when approaching customers from the food industry. Outcomes of the qualitative interviews also suggest that there is limited knowledge about AM in the food industry. There is also a knowledge gap about the regulations and possibilities to use AM in the food industry based on these regulations.

    Indeed, food manufacturers are interested in the adoption of newer technologies and present the researchers with the formation of various themes to develop strategies for adoption of AM, through a recommendable marketing, sales and aftersales strategy that can be employed by AM companies.

    Ladda ner fulltext (pdf)
    Adoption of Additive Manufacturing in the Food Industry
  • 20.
    Fakoya, Moyosore Babatomide
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för materialvetenskap. Uppsala University.
    Effect of Heat Treatment on the Microstructure and Hardness Property of Additively Manufactured Ti6Al-4V and Ti-6Al-4V-4.5wt.%316L Componentsfor Biomedical Applications.2023Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    AbstractThe continuous advancement of medical implants technology presents exciting possibilities.Laser Powder Bed Fusion (L-PBF) additive manufactured Ti-6Al-4V alloy implants showtremendous promise as they offer the potential for highly personalized implants, improved implantfunctionality and enhanced long-term outcomes. However, the microstructure and microhardnessproperty of components produced through L-PBF are inferior when compared to theircounterparts manufactured using traditional methods. Recent investigation presents aninnovative method that has potential to address these microstructure and microhardnesschallenges. This method creates a spatially modulated Ti alloy by adding 316L powder into Ti-6Al-4V powder before printing with L-PBF. The resulting alloy shows a reduced formation ofcoarse β columnar grains into more preferred equiaxed grains. However, the effect of heattreatment operation on this spatially modulated alloy has not yet been explored.Thus, this present study reports on the effect of heat treatment operation on the microstructureand hardness property of Laser Powder Bed Fusion (L-PBF)- fabricated Ti-6Al-4V and Ti-6Al-4V-4.5wt.%316L alloys respectively. The heat treatment processes include both super- and sub- betatransus temperature (Tβ). After the heat treatment processes, the samples were either water-quenched or air-cooled. X-ray Diffraction (XRD), Light Optical Microscopy (LOM), and ScanningElectron Microscopy (SEM) were the characterization techniques performed on these alloys andthese qualitative data gathered were correlated with their microhardness measurements. The as-fabricated Ti-6Al-4V alloy exhibited a martensite α՛ microstructure. On the other hand, the Ti-6Al-4V-4.5wt.%316L alloy possessed a β grain structure. Ti-6Al-4V alloy, subjecting it to the 1020˚Csuper-transus treatment followed by water quenching resulted in the formation of new α՛martensite microstructure and fine primary alpha. When the Ti-6Al-4V specimen was subjectedto 1020˚C and then air cooled, a bimodal microstructure comprising coarse primary alpha andα+β lamellar was formed. The 920˚C sub-transus heat treatment also produced α+β lamellarstructure. For the 1020˚C water-quenched Ti-6Al-4V sample, the microhardness value increasedby 7.3% and 11% in the transverse and cross-sections to the build direction axis, respectivelywhen compared to the as-built parts. Conversely, Ti-6Al-4V-4.5wt.%316L alloy exhibited evenlydistributed primary alpha plates in beta matrix for both the water-quenched and air-cooledsamples at 1020˚C and 920˚C. On the other hand, heat treatment at 800 ˚C retains the as-builtbeta grain morphology while alpha plates precipitate along the grain boundaries. Themicrohardness results suggest that performing only transus heat treatment on the Ti-6Al-4V-4.5wt.%316L alloy was insufficient to significantly alter its hardness properties.Key words: Additive manufacturing, Ti-6Al-4V, Laser powder bed fusion, microstructure control.

    Ladda ner fulltext (pdf)
    fulltext
  • 21.
    Feldt, Daniel
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper.
    Hedberg, Petra
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper.
    Jarlöv, Asker
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper.
    Persson, Elsa
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper.
    Svensson, Mikael
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper.
    Vennberg, Filippa
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper.
    You, Therese
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper.
    Independent Project in Chemical Engineering and Materials Engineering: A literature study of powder-based additive manufacturing2018Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    The focus of this literary study was additive manufacturing (AM) and the purpose was to find general trends for selected materials that have been additively manufactured and compare them to results from other reviews. The raw materials studied were stainless steels 316L, 17-4 PH, 15-5 PH and 420, as well as tool steel H13 and nickel alloys 625, 718 and Hastelloy X. The AM techniques studied were selective laser melting (SLM), electron beam melting (EBM) and binder jetting (BJG). 

    A total of 69 articles have been studied to fulfill the purpose above. The articles were used to write a summary of the techniques, compare them to each other and to conventional methods. They were also used to create a database to compile information on mechanical properties, microstructure and process parameters. Based on the database mechanical properties for SLM tend to be higher compared to EBM. This however varied somewhat depending on the processed material. Furthermore the yield and tensile strength obtained from the da