Sökning: "powder metallurgy PM"

Visar resultat 26 - 29 av 29 avhandlingar innehållade orden powder metallurgy PM.

1. 26. Multicomponent diffusional reactions in tool steels : Experiment and Theory

   Författare :Greta Lindwall; Malin Selleby; Karin Frisk; John Ågren; Carelyn Campbell; KTH; []
   Nyckelord :hot-work tool steel; precipitation hardening; DICTRA; coarsening; mobilities; CALPHAD; cobalt; PM tool stees; nitrogen; compound materials;

   Sammanfattning : Many phenomena determining the microstructure of a tool steel and consequently the properties of the material, are governed by multicomponent diffusion. The diffusion driven reactions that take place during, for example, tempering of a hot-work tool steel or when the microstructure develops during hot isostatic pressing of cold-work tool steel, are dependent on the types and amounts of alloying elements. LÄS MER

3. 27. High Performance Manufacture of Sintered Steel – Critical Aspects of Tooling Performance and Sintered Microstructure

   Författare :Sepehr Hatami; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Tool Steels; Chromium Alloyed Steel; Modelling; Process Selection; Sinter-Hardening; Atmosphere; Microstructure; Galling; Pressing Dies; Wear;

   Sammanfattning : Steel is the dominant material for the production of structural parts. By means of powder metallurgy (PM) processing, manufacturers have been able to manufacture steel parts with appreciable dimensional accuracy and desirable mechanical properties. LÄS MER

4. 28. Critical Aspects of High Performance Manufacturing of Structural Sintered Steel

   Författare :Sepehr Hatami; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Tool Steels; Modelling; Controlled Atmosphere; Wear Mechanisms; Sintering; Pressing Dies; Chromium Alloyed Steel;

   Sammanfattning : Steel is the dominant material for the production of structural parts. By means of powder metallurgy (PM) processing, manufacturers have been able to manufacture steel parts with appreciable dimensional accuracy and proper mechanical properties. LÄS MER

5. 29. Structural Silicides - Processing, Microstructure and Toughening

   Författare :Danqing Yi; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; toughening; solid solubility; processing; microstructures; mechanical properties; composites; silicides; crystal structure; alloying effects; phase transformation;

   Sammanfattning : Molybdenum disilicide is a promising candidate material for high temperature structural uses. However, its room-temperature toughness is rather low and has to be improved. The objective of this thesis is to improve the fracture toughness of MoSi2 by alloying and composite processes. LÄS MER