TRIMMING PROCESSES FOR ADVANCED STEELS

Greater quality control improves automotive manufacturing trimming processes for high-strength steels, resulting in reduced levels of scrap.

AS A PARTICIPANT OF ONE of the National Science Foundation's Research Experiences for Undergraduates (REU) grant programs, I had the opportunity to conduct research impacting manufacturing within the automotive industry. The resulting data was significant enough for submission as an SAE International technical paper, “Characterization of Trimmed Edge of Advanced High Strength Steel” (2016-01-0358), and was shared with industry members. An overview of the research results presented in the paper is given here.

With the rising automotive industry demand for stronger, lighter, and more fuel efficient vehicles, all areas of the industry must push the evolution of materials and technology. Within manufacturing, this has led to the use of lighter and stronger dual-phase advanced- and ultra-high-strength steels (AHSS and UHSS), such as DP980. Changing the microstructure of steels to create AHSS and UHSS also changes the behavior of the steels when exposed to stresses, and this can significantly affect the trimming processes used in manufacturing. Poor trimming quality of AHSS or UHSS components can result in splitting and cracking along the sheared edge, essentially turning the components into unusable scrap. Using the conventional trimming process of a mechanical press (the steel sheet is free to bend at trimming location), the research investigated the impact of cutting clearance and tool wear on the trimming quality of DP980. Additionally, to ensure a better understanding of the effect material has on the trimming quality, two additional steels, high-strength steel (HSLA350) and interstitial free mild steel (IF), which were used previously in manufacturing, also were tested under new tool conditions.