Sökning: "Ultra-High Strength Steel"

Visar resultat 11 - 15 av 21 avhandlingar innehållade orden Ultra-High Strength Steel.

1. 11. Prediction of hardening, localization and fracture of multiphase microstructure in boron alloyed steel

   Författare :Stefan Golling; Daniel Berglund; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Hållfasthetslära; Solid Mechanics;

   Sammanfattning : Over recent years the demand of press hardened ultra-high strength steel for safety structures in automobiles has increased and continuation of this trend is expected.Components with tailored material properties can be manufactured using a thermo-mechanical process with heated and cooled areas in a tool. LÄS MER

3. 12. Hot forming tribology : galling of tools and associated problems

   Författare :Leonardo Pelcastre; Ewald Badisch; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Maskinelement; Machine Elements; Centrumbildning - Centrum för högpresterande stål CHS ; Centre - Centre for High Performance Steel CHS ;

   Sammanfattning : In recent years, the use of ultra high-strength steels (UHSS) as structural reinforcements and in energy-absorbing systems in automobiles has increased rapidly; mainly in view of their favourable strength to weight ratios. However, due to their high strength, the formability of UHSS is poor, thus complex-shaped UHSS components are invariably produced through hot-metal forming processes. LÄS MER

4. 13. High temperature galling : influencing parameters and mechanisms

   Författare :Leonardo Pelcastre; Jens Bergström; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Maskinelement; Machine Elements; Centrumbildning - Centrum för högpresterande stål CHS ; Centre - Centre for High Performance Steel CHS ;

   Sammanfattning : Damage of forming tools at elevated temperatures is a major problem in metal forming processes such as hot stamping. Of special importance is the occurrence of adhesion and gross material transfer from the work-piece to the tool surface, a phenomenon known as galling. LÄS MER

5. 14. Integrated Experimental and Computational Study of Precipitation in Martensitic Steels

   Författare :Tao Zhou; Peter Hedström; David San Martin; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Precipitation; Martensite; Modelling; Thermodynamics; Mechanical Property; Transmission Electron Microscopy; Materials Design; Teknisk materialvetenskap; Materials Science and Engineering;

   Sammanfattning : Precipitation is a phase transformation process in metallic materials that significantlyaffects properties. The precipitation process that includes nucleation, growth andcoarsening of small particles can be tuned by alloying, deformation, thermal treatment. LÄS MER

7. 15. Material characterisation for simulation of press hardening

   Författare :Paul Åkerström; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Hållfasthetslära; Solid Mechanics;

   Sammanfattning : The growing effort to reduce vehicle weight and improve passive safety in the automotive industry has drastically increased the demand for ultra high strength steel components. There exist several production methods for such components, where the press hardening technique (hot stamping) is one of the most successful in producing complex components from boron steel. LÄS MER