Sökning: "Ni-Fe"

Visar resultat 1 - 5 av 14 avhandlingar innehållade ordet Ni-Fe.

1. 1. Additive Manufacturing of Ni-Fe Superalloys : Exploring the Alloying Envelope and the Impact of Process on Mechanical Properties

   Författare :Carl Johan Hassila; Urban Wiklund; Staffan Jacobson; Johan Moverare; Uppsala universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Additive manufacturing; alloying for AM; PBF-LB; microstructure; tensile and impact testing; Teknisk fysik med inriktning mot tribomaterial; Engineering Science with specialization in Tribo Materials;

   Sammanfattning : Additive manufacturing of metals has received a lot of attention in the last decade as this family of manufacturing processes allows the manufacturing of complicated geometries which would be difficult to produce using conventional manufacturing techniques. Additive manufacturing of the Ni-Fe based superalloys 625 and 718 using the Powder Bed Fusion – Laser Beam (PBF-LB) process is facilitated by the fact that these alloys were developed as weldable alternatives to other high-strength, high-temperature Ni-based superalloys. LÄS MER

3. 2. Liquid phase sintering of W-Ni-Fe composites : liquid penetration, agglomerate separation and tungsten particle growth

   Författare :Anders Eliasson; Hasse Fredriksson; Thomas Gomez-Acebo; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Liquid phase sintering; heavy metal; particle composites; tungsten; penetration; agglomerate separation; particle interaction; parabolic flight; sounding rockets; microgravity; Kirkendall effect; Metallurgical process engineering; Metallurgisk processteknik;

   Sammanfattning : The initial stage of liquid phase sintering, involving liquid penetration, agglomerate separation, particle spreading and growth has been investigated in experiments using tungsten heavy alloys. The particle composites used were produced by hot isostatic pressing (HIP) of pure powder mixtures of W-Ni-Fe-(Co). LÄS MER

4. 3. Microstructural Development of Nanocrystalline Ni- and Co-Based Materilas upon Annealing

   Författare :Melina da Silva; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Ni; grain growth; nanocrystalline materials; Co-P; Ni-Fe; thermal stability; TEM in-situ annealing;

   Sammanfattning : Nanocrystalline materials are a relatively new group of materials that are constituted by crystals/grains of a few nanometers in size. Because their mechanical, physical and chemical properties are often superior compared to their microcrystalline counterparts, these materials are attractive for many industrial applications. LÄS MER

5. 4. Powder bed fusion processing of Ni-base superalloys - Defect formation and its mitigation

   Författare :Hans Gruber; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; hot isostatic pressing; Ni-base superalloys; non-metallic inclusions; cracking; additive manufacturing; laser powder bed fusion; defect formation; Alloy 718; powder re-use; IN-738LC;

   Sammanfattning : Powder bed fusion of Ni- and Ni-Fe-base superalloys is actively considered a promising manufacturing technology for critical components for the aerospace and industrial gas turbine industries. Such components often operate under harsh conditions, and hence, high demands are placed on both process and feedstock material to meet the strict safety and long-term reliability requirements. LÄS MER

7. 5. Varestraint Weldability Testing of Cast Superalloys

   Författare :Sukhdeep Singh; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Varestraint; Hot Cracking; Welding; Alloy 718; Cast Superalloys; ATI® 718 PlusTM; HIP;

   Sammanfattning : Precipitation hardened Ni- and Ni-Fe- based superalloys, used in hot structural components for aero engines, are subjected to hot cracking phenomena during manufacturing and specifically in welding. This type of cracking involves metallurgical reactions from the liquid phase in concomitance to weld restraints. LÄS MER