The effects of electro slag welding on material properties of box column plates

Abstract

The effects of electro slag welding (ESW) on the material properties of box column plates, which is ASTM A572 Gr. 50 steel, were investigated experimentally and numerically. The material properties of the column plates before and after ESW were evaluated by macro-etching observation, micro-structural observation, and CVN impact tests. The temperature distribution of the column plates, with the ESW heat cycle as the heat input, was simulated by using the ANSYS FEM software. It was found that: (1) The CVN values in the through thickness direction of the base metal can be as low as 14J, 8.1J, and 8.1J at 0°C for plate thicknesses of 32, 40, and 50 mm respectively; (2) During the ESW process, the measured peak temperature for a 25×50 mm column plate surface was as high as 1033, 880 and 744°C for plate thicknesses of 32, 40 and, 50 mm respectively; (3) After the ESW heat cycle, the through thickness CVN value decreased by 68% for the coarse grain heat affected zone (HAZ) of the column pate; (4) The FEM thermal conduction model developed was able to simulate the temperature distribution of the steel plate during the ESW process with reasonable accuracy; (5) To avoid welding penetration due to ESW, a minimum plate thickness is suggested; (6) The impact of ESW heat cycle is more significant for thin column plates compared to thick ones.