Sökning: "Nitriding"

Visar resultat 1 - 5 av 17 avhandlingar innehållade ordet Nitriding.

1. 1. Mechanical properties and microstructure of laser sintered and starch consolidated iron-based powders

   Författare :Yu Wang; Jens Bergström; Karlstads universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Powder metallurgy; Laser sintering; Microstructure; Fatigue; Thermal fatigue; Wear; Starch consolidation; Rapid forming; Net shaping; Liquid phase sintering; Nitriding; High speed steels; Materials science; Teknisk materialvetenskap; Materialteknik; Materials Engineering;

   Sammanfattning : In powder metallurgy research field, Direct Metal Laser Sintering (DMLS) and Metal Powder Starch Consolidation (MPSC) are relatively new rapid forming techniques to fabricate complex and near net-shaped components. The working principles of DMLS are to melt and fuse metal powder layer by layer in computer controlled systems to pile up components like three dimensional printing. LÄS MER

3. 2. Internal oxidation processing : New alloys and new simulation techniques

   Författare :Henrik Larsson; KTH; []
   Nyckelord :Internal oxidation; nitriding; diffusion; simulation; random walk; TECHNOLOGY; TEKNIKVETENSKAP;

   Sammanfattning : Nitriding and oxidising treatments of alloys for toolingpurposes have been investigated both experimentally andtheoretically. Specimens prepared by a combination of differentprocessing steps are investigated by light-optical, scanningand transmission electron microscopy and hardness measurments. LÄS MER

4. 3. Secondary hardening in some low-chromium hot-work tool steels

   Författare :Jörgen Andersson; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; LEAP; coarsening; nitriding; SEM; TEM; vanadium; precipitation hardening;

   Sammanfattning : Low-chromium hot-work tool steels combine good heat conductivity with excellent tempering resistance. This property combination has made these steels ideal for die casting and extrusion. LÄS MER

5. 4. Low-temperature carburizing/nitriding of austenitic stainless steels - Influence of alloy composition on microstructure and properties

   Författare :Giulio Maistro; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; tribology; surface engineering; S-phase; SEM; corrosion; XPS; Austenitic stainless steel; expanded austenite; plasma nitriding; EBSD; XRD; thermal stability; low-temperature carburizing; surface analysis; GDOES;

   Sammanfattning : Austenitic stainless steels are among the most used materials in applications where corrosion resistance is important, as the food, pharmaceutical, chemical, oil and gas industries. However, low hardness and poor tribological properties is often an obstacle for their applicability. LÄS MER

7. 5. Local structure and composition : in additively manufactured bulk metallic glasses and composites

   Författare :Inga Katharina Goetz; Jochen M. Schneider; Björgvin Hjörvarsson; Ulf Jansson; Maria Teresa Pérez Prado; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; additive manufacturing; bulk metallic glasses; nanoscale clustering; convective flow; laser nitriding; laser powder bed fusion; metallic glass - ceramic composites; oxygen impurities; mechanical properties; magnetic properties; viscosity; Fysik; Physics;

   Sammanfattning : Additive manufacturing enables the production of complex multi-material geometries and bulk metallic glass parts beyond their critical casting thickness. The local modification of structure, composition, and properties is explored in this thesis with the aim to design novel composite materials and functional gradients. LÄS MER