About this Abstract |
| Meeting |
2026 TMS Annual Meeting & Exhibition
|
| Symposium
|
Fatigue in Materials: Fundamentals, Multiscale Characterizations and Computational Modeling
|
| Presentation Title |
Progressive Strain Induced Martensitic Transformation of Retained Austenite and Corresponding Enhancement in Fatigue Crack Growth Resistance in High Strength DQP Steel |
| Author(s) |
Amol A. Gokhale, Gaurav Kumar, Tanmay Bhandakkar`, Sumit Ghosh, Sakari Pallaspuro, Mahesh C. Somani, Jukka Kömi, Sushil K. Mishra |
| On-Site Speaker (Planned) |
Amol A. Gokhale |
| Abstract Scope |
A 0.4%C steel was directly quenched and partitioned (DQP) to produce nanoscale filmy carbon-enriched 11.5% retained austenite (RA), and a yield strength of 1206 MPa. The same steel was directly quenched (DQ) from the rolling temperature to room temperature, which had about 2% RA and 1691 MPa yield strength. In the DQP steel, the RA transformed incrementally to martensite during fatigue crack growth, leaving about 8.3% RA after fracture. Moreover, the resistance to fatigue crack growth was greater for DQP than for DQ steel, and the difference increased with FCG, presumably due to the filmy nature of the RA, which requires higher stresses for inducing transformation. The improved FCG resistance of DQP was attributed to higher contributions of dislocation plasticity (DP) and transformation-induced plasticity (TRIP) to FCG. An attempt was made to theoretically isolate the effects of DP and TRIP on the resistance to fatigue crack growth. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Mechanical Properties, Phase Transformations, Characterization |