Effects of thermal-cold cycling on the dimensional stability of TiC reinforced steel matrix composite

Thermal-cold cycling (TCC) treatment was applied to improve the dimensional stability of TiC reinforced steel matrix composite materials in this study. Also, the microstructure, related properties and potential stability mechanisms were investigated. When the TCC cycles were 3, Vickers hardness reached the peak value of 1051.7 HV and relative dimensional change was only 0.012% in a natural service for 30 days. Besides, the retained austenite disappeared and residual stress dramatically decreased from-740 MPa to-357 MPa. It demonstrated that the TiC reinforced steel matrix composite possessed the best dimensional stability after 3 TCC cycles. A variety of stabilizing mechanisms, including martensitic refinement, retained austenite-martensite transformation, carbides precipitation, and residual stress release were observed, hence resulting in a significantly improvement of the dimensional stability of the composite. (c) 2020 Elsevier B.V. All rights reserved.