Mazda Motor Corporation, working separately with Nippon Steel & Sumitomo Metal Corporation and JFE Steel Corporation, has developed the world’s first cold-stamped vehicle body parts made from 1 310 MPa-class high-strength steel.
The parts are used in Mazda’s new-generation Skyactiv vehicle architecture, which will underpin upcoming models, starting from the all-new Mazda3.
High-strength steel enables automakers to make parts from thinner sheet metal, while retaining the necessary yield strength. This results in a lighter vehicle body, which contributes to improved handling stability and fuel economy.
A strong body is also essential to ensure crash safety performance.
Until now, cold-stamping of vehicle body structural members has only been possible with 1 180 MPa or lower-classed steel, due to the material’s formability and the difficulty of ensuring dimensional accuracy after processing.
However, working in collaboration with the steel industry, Mazda says it has found an appropriate set of processing conditions that make the process possible with 1 310 MPa-class high-strength steel.
The all-new Mazda3 uses 1 310 MPa-class high-strength steel for the front pillar inner, the roof rail inner, the hinge pillar reinforcement, the roof rail reinforcement, the number 2 crossmember and the side sill inner reinforcement, saving about three kilograms over the same parts in the previous model.