Transvarestraint testing of high-strength steel filler metal

Abstract High-strength steel welds are typically not known to be susceptible to Solidification Cracking (SC). However, modern light-weight constructions may force welding in highly restrained conditions, which are known to increase the probability of Solidification Crack (SC) emergence. In this article, the Modified Varestraint-Transvarestraint (MVT) test was used to evaluate the hot cracking susceptibility of welds made from high-strength, low-alloyed filler material. The materials tested include solid wires and a metal-cored wire. All wires are typically used in the Gas Metal Arc Welding (GMAW) process. Susceptibility to SC was measured over a wide range of welding parameters and bending speeds. Results show little affinity of the tested materials to SC. However, crack length increases in most cases with arc energy ( $$\text{U}\bullet \text{I}/\text{welding speed}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mtext>U</mml:mtext> <mml:mo>∙</mml:mo> <mml:mtext>I</mml:mtext> <mml:mo>/</mml:mo> <mml:mtext>welding speed</mml:mtext> </mml:mrow> </mml:math> ) and welding speed. The length of the longest crack in one test specimen follows a similar trend until high welding speeds, where stagnation of crack length with changing arc energy was observed.