Mazda Motor Corporation has successfully developed the first-ever cold-stamped vehicle body parts using 1,310 MPa-class high-strength steel. This will mainly make up the new-generation Skyactiv-Vehicle Architecture, which will be used in Mazda’s future models starting from the 2019 Mazda3.
The all-new Mazda3 debuted at the 2018 Los Angeles Auto Show, boasting the all-new Skyactiv-X engine. It bore what Mazda calls “less is more” KODO design language, which continues further inside the cabin. Available in hatch and sedan bodies, the Mazda3 is bound to come in five engine types, 1.5-, 2.0- 2.5-liter Skyactiv-G gasoline engines, a 1.8-liter Skyactive-D diesel mill, and the aforementioned all-new Skyactiv-X engine.
Going back to the high-strength steel, this particular grade of metal in the form of thin sheets makes it ideal for car manufacturers as it is light. Using this kind of steel in building the car’s chassis, the car’s handling, stability, and fuel economy are improved. In addition, a strong body ensures crash safety performance.
Cold-stamping is the process of pressing, cutting, and molding sheets of metals to form various parts of an automobile. Some may recognize the process as press-working, an operation where sheets of metal are pressed by a machine to achieve certain molds. As its name suggests, the process doesn’t require pre-heating of the metal. Rather, a machine applies pressure on the sheets, and this is measured by Megapascal (MPa).
Normally, cold-stamping can only be done using 1,180 MPa on lower-classed steel sheets (or blanks) because of issues in dimensional accuracy and material’s formability. Mazda was able to overcome this challenge, and made a 1,310 MPa high-strength steel-cold stamp possible. Thanks to its partners Nippon Steel & Sumitomo Metal Corporation and JFE Steel Corporation, cold-stamping with 1,310 MPa on high-strength blanks will now be a thing for future cars, especially for Mazda’s future lineup.
For its application on the all-new Mazda3, high-strength steel will be used as the material for the front pillar inner, roof rail inner, hinge pillar reinforcement, roof rail reinforcement, No. 2 crossmember, and the side sill inner reinforcement. This, in return, is projected to save 3 kg compared to the usual parts found on the previous model.