[Back]

N. Große-Heilmann, I. Zylla, E. Kozeschnik, A. Peters:
"High Strength TRIP Steels processed by Two-step Quenching & Partitioning";
Talk: 4th International Conference on Steels in Cars and Trucks, Braunschweig; 2014-06-15 - 2014-06-19; in: "4th International Conference on Steels in Cars and Trucks", (2014), 731 - 737.

The Application of Ultra High strength martensitic steels with yield strength above 1000 MPa in automotive lightweight components is often limited by insufficient ductility. Ultra High Strength TRIP assisted martensitic steels processed by twostep Quenching and Partitioning (Q&P) offer the opportunity to achieve weight savings by higher strength together with higher ductility, toughness, fatigue strength and at reasonable cost.
To show the potential of the two-step Q&P heat treatment in seamless tube production, corresponding tests are carried out on 42SiCrB lean alloyed steel. Inductive austenitization and partitioning are applied in conjunction with salt bath quenching. The stability of retained austenite after partitioning is predicted using Constrained-Carbon-Equilibrium (CCE) model. The resulting properties and microstructures of the simulated material are analyzed by mechanical testing and x-ray diffraction.
Compared to common quenched and tempered 30CrMo4 steel the ductility of Benteler Q&P steels is enhanced significantly.

martensite, quenching, partitioning, retained austenite, TRIP, seamless, steel, tube