This part is located on the front side of the front doors of automobiles. It has a great impact on safety as it protects the driver, so it must be made incredibly strong. Hiraoka Body uses high tensile strength steel panels called ultra high strength steel, with a tensile strength of 1 GPa. Because ultra high strength steel can be used to make panel thickness thinner and heavy parts lighter, it is attracting a great deal of attention in the current automotive industry, but its strength also makes it an extremely difficult to mold materials. Typical press methods lead to fractures and springback, making it difficult to maintain precision. In our development process, we reflect the results produced by molding simulation software on our prototype molds and compare the actual product with simulation results to shorten lead time while realizing high precision products.

This reinforcement part is combined with the dash side panel described above. As with the dash side panel, we use ultra high strength steel for this part. Yet while normal ultra high strength steel has a panel thickness of about 1.00 mm to make itself light, this part uses material that is 2.00 mm thick because its purpose is reinforcement. Machining this kind of thick, high strength material requires not only normal high tensile strength steel technology, but also product development and metal molding technology with an understanding of the material properties possessed by thick high tensile strength steel plating.