Pressed steel parts manufacturer Gestamp has developed what it says is its fourth-generation hot stamping process. The company has been producing hot-stamped parts for a number of years, supplying complete door rings for the American market and parts for door inners, which are said to reduce the weight of the inner doors by 20%. The latest application for hot-stamped parts are the battery boxes for electric vehicles, and these have presented both OEMs and tier suppliers with a set of new challenges.

Ignacio Martín González, general director of body-in-white (BIW) R&D, explains how the new Multi-Step hot stamping technology at the company’s Bielefeld plant in Germany will advance the production of high-strength steel parts: “This fourth-generation technology allows us to achieve several goals; we can reduce the weight and the cost of the parts. Also we can increase the performance. This is exactly what the EV market is expecting from us. We can see there’s a move from steel to a multi-material mix gradually coming into electrical vehicles and this is mainly driven by the battery boxes.”

One of the biggest challenges has been creating a suitably strong but lightweight structure for the battery box on EVs. This has to meet a number of strict criteria for crash resistance and weather proofing, as well as being an integral part of the vehicle’s structure. The EV BIWs have to be manufactured in high volumes, cost effectively and offer flexible platforms for multi-model applications…