Resistance spot welding studies at varying current with an 8 mm electrode on steel grades DP980, DP690, TRIP980 and TRIP780, established that peak strength sound weld could be achieved a range of 9 to 10 kA, where the nugget diameter was between 6.9 7.5 mm. The joint efficiency, measured as hardening ratio highest in TRIP690 2.22 for higher grade it 1.37 1.51. softening HAZ associated tempering...

To overcome the trade-off relationship between tensile strength and elongation of dual-phase steels, three exploratory techniques were utilized: Bayesian optimization (BO), BoundLess Objective-free eXploration (BLOX), one-class support vector machine (OCSVM). The BO is an method using Gaussian process regression, BLOX OCSVM are designed for finding out-of-trend materials. Initially, a large num...