Sökning: "nitrogen alloying"

Visar resultat 1 - 5 av 34 avhandlingar innehållade orden nitrogen alloying.

1. 1. The Positive Effect of Nitrogen Alloying of Tool Steels Used in Sheet Metal Forming

   Författare :Irma Heikkilä; Staffan Jacobson; Sture Hogmark; Pavel Krakhmalev; Uppsala universitet; []
   Nyckelord :galling; nitrogen; tool steel; sliding contact; metal forming; Teknisk fysik med inriktning mot tribomaterial; Engineering Science with specialization in Tribo Materials;

   Sammanfattning : Sheet metal forming processes are mechanical processes, designed to make products from metal sheet without material removal. These processes are applied extensively by the manufacturing industry to produce commodities such as heat exchangers or panels for automotive applications. They are suitable for production in large volumes. LÄS MER

3. 2. Microstructure and properties of welds in the lean duplex stainless steel LDX 2101

   Författare :Elin M. Westin; John Ågren; Hannu Hänninen; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Duplex stainless steel; welding; HAZ; nitrogen; manganese; microstructure; austenite formation; phase balance; precipitates; element distribution; segregation; depletion; solidification; pitting corrosion resistance; solidification; element loss; evaporation; deposition; weld oxide; thermo-mechanical simulation; thermodynamic modelling; EPMA; XPS; post-weld cleaning; pickling; Metallurgical process and manufacturing engineering; Metallurgisk process- och produktionsteknik;

   Sammanfattning : Duplex stainless steels can be very attractive alternatives to austenitic grades due to their almost double strength at equal pitting corrosion resistance. When welding, the duplex alloys normally require addition of filler metal, while the commodity austenitic grades can often be welded autogenously. LÄS MER

4. 3. 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

5. 4. Initiation and Repassivation of Pits on Austenitic Stainless Steel

   Författare :Fredrik Falkenberg; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; chloro complex; pitting corrosion; metastable pits; phosphate; nitrogen; passive film; chloride; repassivation; molybdenum; austenitic stainless steel;

   Sammanfattning : Stainless steels can be damaged by pitting corrosion in presence of aggressive anions, such as halide ions. The aim of this work was to study different aspects on initiation and repassivation of pits on austenitic stainless steel in chloride solutions at ambient temperature. LÄS MER

7. 5. Deformation and Fatigue Behaviour of Porous and Dense Austenitic Stainless Steel

   Författare :Ulf Lindstedt; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; mechanical properties; austenitic stainless steel; PM steel; nitrogen; small cracks; previous particle boundaries; microplasticity; grain size dependence; fatigue; porosity;

   Sammanfattning : PM stainless steels are increasing in use and are expected to do so in the future. A lot of work has been carried out concerning production and sintering of stainless steel powders and on the resulting corrosion behaviour. The deformation behaviour of these materials is less studied. LÄS MER