Effect of Heat Input on Porosity in High Nitrogen Steel Composite Welds

High-nitrogen steel plates with a thickness of 8 mm are welded with a laser-arc composite heat source for experiment to study the impact of different heat input parameters on the blowhole defect. The results show that with the increase of laser power, welding current and arc voltage, the porosity of welds decreases; with the increase of welding speed, the porosity of welds increases. Appropriately increasing the heat input helps reduce the porosity of the weld