不同沉积路径冷金属过渡电弧增材制造H13钢成形件的显微组织和硬度

Microstructure and Hardness of CMT Wire-Arc Additive Manufactured H13 Steel Formed Parts in Different Deposition Paths

在不同沉积路径下采用冷金属过渡电弧增材制造技术制备了H13钢成形件,基于热-弹塑性有限元法对成形件的热历程进行了分析,并通过试验研究了成形件的显微组织和硬度。结果表明:同向和双向路径沉积得到5层单道和单层5道成形件的热历程基本一致,双向沉积5层单道成形件第3层中间点的峰值温度远高于双向沉积单层5道成形件第3道中间点,5层单道成形件的热累积效应更明显;5层单道成形件的板条状马氏体组织比单层5道成形件的粗大;同向沉积5层单道成形件在同一高度上的硬度略高于双向沉积成形件,同向沉积和双向沉积单层5道成形件在水平方向的硬度分布基本相同,5层单道成形件的平均硬度略低于单层5道成形件。

H13 steel formed part was prepared by cold metal transfer wire-arc additive manufacturing in different deposition paths. Based on the thermo-elastic-plastic finite element method, the thermal history of the formed part was studied. The microstructure and hardness evolution of formed part was studied by tests. The results show that the thermal history of the 5-layer single-pass and single-layer 5-pass formed part deposited in the codirection and bidirection path was basically the same. The peak temperature of the middle point of the third layer of bidirection deposited 5-layer single-pass formed part was much higher than that of the middle point of the third pass of bidirection deposited single-layer 5-pass formed part, and the heat accumulation effect of the 5-layer single-pass formed part was more obvious. The lath martensite structure of 5-layer single-pass formed part was coarsened than that of single-layer 5-pass formed part. The hardness of the codirection deposited 5-layer single-pass formed part at the same height was slightly higher than that of bidirection deposited formed part, and the hardness of the codirection deposited and bidirection deposited 5-layer single-pass formed part was basically the same. The average hardness of the 5-layer single-pass formed part was slightly smaller than that of single-layer 5-pass formed part.