Sökning: "Pia Åkerfeldt"

Visar resultat 1 - 5 av 6 avhandlingar innehållade orden Pia Åkerfeldt.

1. 1. Additive Manufacturing of Ti-6Al-4V: Relationship between Microstructure, Defects and Mechanical Properties

   Författare :Pia Åkerfeldt; Barbara Shollock; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Materialteknik; Engineering Materials;

   Sammanfattning : Additive manufacturing (AM) is a relatively new technology that is labelled to be innovative, disruptive, near-net shaping, enabling manufacturing of complex and customised products, for limitless number of applications, directly from the CAD model into real physical parts. For titanium alloys in aerospace applications, AM moreover stands for a reduced material cost, but also for large challenges when considering consistency and qualification of material properties and components in serial production. LÄS MER

3. 2. Solid metal induced embrittlement of titanium alloys

   Författare :Pia Åkerfeldt; Melina da Silva; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Materialteknik; Engineering Materials;

   Sammanfattning : Titanium alloys were for a time believed to be highly resistant to environmentally assisted cracking because of their ability to form a protective oxide film on the surface. Their resistance can still be considered to be high, but when cracking resistance was originally defined to ensure reliable functionality of fracture-critical components, certain conditions that promote cracking were discovered. LÄS MER

4. 3. Microstructure and hydrogen embrittlement of additively manufactured Ti-6Al-4V

   Författare :Magnus Neikter; Marta-Lena Antti; Pia Åkerfeldt; Robert Pederson; Ola Harrysson; Luleå tekniska universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Ti-6Al-4V; Additive Manufacturing; Texture; Microstructure; Hydrogen Embrittlement; Materialteknik; Engineering Materials;

   Sammanfattning : The work of this doctoral thesis has been performed between the 24th of August 2015 to the 6th of September 2019. The general purpose of this work has been to increase the knowledge of additively manufactured Ti-6Al-4V when it comes to microstructure, texture and hydrogen embrittlement. LÄS MER

5. 4. Effect of Stress Relief Annealing: Part Distortion, Mechanical Properties, and Microstructure of Additively Manufactured Austenitic Stainless Steel

   Författare :Emil Edin; Marta-Lena Antti; Pia Åkerfeldt; Fredrik Svahn; Magnus Neikter; Paul Åkerström; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Laser powder bed fusion; stainless steel; residual stress; heat treatment; tensile testing; relaxation testing; Materialteknik; Engineering Materials;

   Sammanfattning : Additive manufacturing (AM) processes may introduce large residual stresses in the as-built part, in particular the laser powder bed fusion process (L-PBF). The residual stress state is an inherent consequence of the heterogeneous heating and subsequent cooling during the process. LÄS MER

7. 5. Defects and Surfaces and their Impact on Fatigue Behaviour of Powder Bed Fused Ti-6Al-4V : Characteristics and Modelling

   Författare :Viktor Sandell; Marta-Lena Antti; Pia Åkerfeldt; Thomas Hansson; Stefano Beretta; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Defects; Additive Manufacturing; Ti-6Al-4V; Probabilistic Modelling; Fatigue; Extreme Value Statistics; Materialteknik; Engineering Materials;

   Sammanfattning : Additive manufacturing (AM), of metals is gaining popularity as an alternative to conventional manufacturing techniques such as casting and forging. Metal-AM allows for the production of complex part geometries with reduced material waste and shorter lead times. LÄS MER