Military — Tougher tanks

Improving welds of heavy and light armored fighting vehicles is the target of a collaboration among Oak Ridge National Laboratory, the U.S. Army Tank Automotive Research, Development and Engineering Center, and ArcelorMittal USA. While military vehicle designs use high-strength steels, hydrogen-induced cracking and weld fatigue are persistent challenges, according to Zhili Feng of ORNL’s Materials Science and Technology Division. Feng and colleagues are developing special weld wire chemistries and conducting tests to solve this long-standing issue. The newly developed welding wire reduces the high-tensile residual stresses in the weld region, eliminating one of three key factors for hydrogen-induced cracking during welding.