Microstructural evolution of Dual Phase steel. Improvement of damage resistance

Abstract : In the automotive industry current environmental concerns require that the vehicle fuel consumption and CO2 emissions should be reduced as much as possible. It is therefore advantageous to reduce the weight of body in white components by replacing existing parts with higher strength, thinner gauge alternatives with equivalent or improved functional properties. Dual Phase (DP) steels are a class of high-strength low-alloy steels characterized by a microstructure consisting of martensite and ferrite. Dual Phase steels combine high strength levels with good ductility. Thus, DP steels are potentially very attractive for the automobile industry. In addition to the required high strength and ductility, DP steel has to be cold formed into complex shapes. It appears that DP steel damage behaviour is very complex and cannot be predicted using existing models based on standard mechanical properties. This work is concerned with the study of microstructural evolution and investigation of the relation between the microstructure and damage mechanisms in a reference DP 780 steel. Two damage mechanisms have been identified in this DP steel: ferrite/martensite interface decohesion and void formation at tempered carbides. A simple modeling for qualitative description of the observed damage formation mechanisms is proposed. This modeling permits a basic understanding of the experimentally observed trends and could be used as the starting point for a more detailed analysis in future
Document type :
Theses
Complete list of metadatas

Cited literature [64 references]  Display  Hide  Download

https://hal.univ-lorraine.fr/tel-01748776
Contributor : Thèses Ul <>
Submitted on : Thursday, March 29, 2018 - 11:48:55 AM
Last modification on : Wednesday, September 4, 2019 - 2:06:03 PM
Long-term archiving on: Friday, September 14, 2018 - 8:34:47 AM

File

2009_PUSHKAREVA_I.pdf
Files produced by the author(s)

Identifiers

  • HAL Id : tel-01748776, version 1

Citation

Irina Pushkareva. Microstructural evolution of Dual Phase steel. Improvement of damage resistance. Other. Institut National Polytechnique de Lorraine, 2009. English. ⟨NNT : 2009INPL084N⟩. ⟨tel-01748776⟩

Share

Metrics

Record views

38

Files downloads

211