Manufacturing of Low and High-carbon TRIP Steels by Modeling CCT Diagrams, Design of Microstructure Maps and Tensile Properties

Although TRIP steels are the first-generation steel for the automotive industry, their high strength, formability, and strength after forming are versatile and widely used automotive steel. This study attempts to evaluate the automotive TRIP steels' manufacturing chains, thermal process, microstructure, and tensile properties via experimental modeling (CCT diagrams-microstructure maps) on two steel groups with low cost. The TRIP Steels manufacturing chains are chemical design, investment casting, hot rolling, and TRIP thermal processes modeling and applications. Experimental techniques performed on samples, meaning characterizations, are image analysis, XRD, hardness, and tensile tests. The results showed that a small amount of martensite transformation occurs during air cooling after the bainitic retention because of the low alloy content. As a result, modeling and microstructure maps have been successfully combined and studied in detail to design and manufacture the TRIP sheet steel.