Wear Study of Mechanical Clinching Dies During Joining of Advanced High-Strength Steel Sheets

This study is focused on the wear of the die cavity of the mechanical clinching tool used for joining microalloyed hot-dip galvanized advanced high-strength steel sheets H220PD+Z. Steel sheets were joined using round, single stroke clinching with rigid die with no flexible elements. The joint forming process takes place within the specially formed cavity of the die. Dies and punches for the mechanical clinching were made of tool steel (1.3343 grade) and subsequently covered by three types of PVD coatings: ZrN, CrN, and TiCN ones. The individual die wear was evaluated during the operation period, which means that 300 joints were produced by each die covered with the corresponding coating. The experimental data obtained were compared with the results of FEA numerical simulation, which substantiated the fact that the dominant part of wear is localized in the radius area surrounding the die cavity.