A four parameter hardening model for TWIP and TRIP steels

Stacking Fault Energy and Microstructural Insight into the Dynamic Deformation of High-Manganese TRIP and TWIP Steels

The dynamic behavior of three high manganese steels with very different stacking faultenergy (SFE) values (4-30 mJ/m2) were studied using high strain rate torsional tests. The hotrolledmicrostructure of the steel with the lowest SFE of 4 mJ/m2 consisted of a duplex mixture ofaustenite and ε-martensite, but those of the other two steels were fully austenitic. The deformedmicrostructures were stu...

Duplex Hardening of Steels for Aeroengine Bearings

Duplex hardening is a process in which conventional heat-treatments such as secondary or case hardening are followed up by surface nitriding to achieve exceptional properties, particularly in the context of aeroengine bearings. Hardness values in excess of 1 000 HV can in principle be achieved, and although the hardness decreases as a function of depth below the surface, some level of enhanceme...

Plastic strain due to twinning in austenitic TWIP steels

Twinning induced plasticity steels are austenitic alloys in which mechanical twinning is a prominent deformation mode, and which exhibit exceptional combinations of ductility, work hardening and ultimate strength. The authors develop in the present paper a crystallographic theory to enable the quantitative investigation of the role of mechanical twinning in enhancing the properties of these all...

Experimental determination of TRIP-parameter K for mild- and high-strength low-alloy steels and a super martensitic filler material

A combined experimental numerical approach is applied to determine the transformation induced plasticity (TRIP)-parameter K for different strength low-alloy steels of grade S355J2+N and S960QL as well as the super martensitic filler CN13-4-IG containing 13 wt% chromium and 4 wt% nickel. The thermo-physical analyses were conducted using a Gleeble (®) 3500 facility. The thermal histories of the s...

Secondary Hardening in High Speed Steels