Effects of martensite morphology dynamic torsional behavior in dual phase steels
- Pohang Univ. of Science and Technology (Korea, Republic of). Center for Advanced Aerospace Materials
- Korea Inst. of Machinery and Materials, Changwon (Korea, Republic of). Materials Engineering Dept.
In the strategic industrial sectors such as defense, automotive, precision machine, and space aircraft industries, the demand for structural materials which can be used under severe conditions like dynamic loading has been rising. The lower resistance to deformation and fracture under dynamic loading than under quasi-static loading can fatally affect overall fracture toughness of structural materials. Thus, detailed studies should be made to be able to maintain the deformation and fracture resistance through effective and quantitative evaluation on them, so that the materials can be widely applied to various fields. Because fracture toughness can drastically drop under dynamic loading in the structure containing brittle phase of martensites, especially like in the dual phase steels, it is highly required to clarify the mechanism. This can basically explain the martensite formation and its effect, and the deformation and fracture process under dynamic loading in a more microscopic level. The present study attempted to investigate the micromechanism of dynamic deformation and fracture which affects the martensite morphology by varying the heat-treatment conditions in the ferrite+austenite ({alpha}+{gamma}) temperature region. Dynamic torsional tests using a torsional Kolsky bar were conducted on two kinds of ferrite+martensite dual phase steels. These steels do not have the same martensite morphology, but have a certain volume fraction of about 50%. Detailed investigations were also made on various factors determining the characteristics of dynamic deformation occurring in martensites by observing deformed microstructures and fracture surfaces.
- OSTI ID:
- 585965
- Journal Information:
- Scripta Materialia, Vol. 38, Issue 1; Other Information: PBD: 18 Dec 1997
- Country of Publication:
- United States
- Language:
- English
Similar Records
An empirical approach to strain to fracture of two-ductile-phase alloys. [Ti-Mn alloys and ferrite-martensite steels]
Characterization of the Fracture Toughness of TRIP 800 Sheet Steels Using Microstructure-Based Finite Element Analysis