Laser weldability of high-strength steel sheets in fabrication of tailor welded blanks

摘要

This article examines the conditions required for TWB welds with a high sheet thickness ratio of up to 3, such as high-strength steel sheets, and further clarifies the basic characteristics of TWBs, such as the mechanical properties, fatigue strength, and press formability of TWBs with a tensile strength of more than 590 MPa. The results obtained may be summarised as follows. Required properties of welds A weld thickness ratio T_w/T_1 of 0.8 or more must be maintained regardless of the steel grade and sheet thickness ratio (T_w being the weld thickness and T_1 the sheet thickness on the thinner sheet side).