Analytic temperature field solution of dual laser welding heat sources and application in static recrystallization

The explicit temperature function of dual laser welding was presented, and the effect of welding pass distance and heat source distance on the thermal history was analyzed. There was excellent correlation between analytically solved and finite element method (FEM)-predicted dual laser welding temperature field. The analytical temperature function is applied to study the static recrystallization kinetics upon dual laser welding of nanobainite steel. By calculation, the optimal welding process parameters can be obtained when the static recrystallization fraction takes the maximum value. The corresponding temperature is above the martensite transus temperature and is appropriate to produce sufficient plastic strain in the austenite grains.