Q235钢电弧增材制造工艺分析及优化OA

To explore the wire arc additive manufacturing process of Q235 steel,the effects of single factors such as current,voltage,and welding speed on weld bead formation are examined.Combined with finite element simulation analysis of the temperature field and stress field,the optimal process parameters were obtained for additive manufacturing experiments.The results indicate that at a voltage of 16 V and a welding speed of 4 mm/s,discontinuities occur in the weld at a current of 90 A,uniform formation is achieved at 110 A,and severe spatter occurs at 130 A.Increasing voltage alone increases the weld width and reduces the weld height,with stable formation observed at voltages between 20 V and 24 V.Increasing the welding speed leads to shallower penetration and incomplete fusion defects.The optimized process parameters are a current of 110 A,a voltage of 20 V,and a welding speed of 5 mm/s.The finite element simulation shows that the temperature field during the welding process of this parameter exhibits a trailing distribution.The stress field gradually expands with the accumulation of heat input,and the peak stress reaches 292.82 MPa,indicating that this process meets the requirements of additive manufacturing.The effective forming widths at the bottom,middle and top of the specimen were 4.88 mm,4.91 mm and 5.01 mm respectively,and the maximum forming widths were 5.57 mm,5.96 mm and 5.91 mm respectively.The microstructure of the specimen was mainly ferrite and pearlite,with fine grains at the bottom,coarser grains in the middle due to heat accumulation,and finer grains at the top but with dendrites.The droplet transition mode during the additive manufacturing process was short-circuit transition,with droplet sizes close to the diameter of the welding wire,and the molten pool had relatively clear bright zone boundaries and was relatively symmetrical.