93W-7Ni激光粉末床熔融增材制造研究

Research on Laser Powder Bed Fusion Additive Manufactured 93W-7Ni alloy

摘要:

以W颗粒和Ni颗粒预先混合的93W-7Ni粉体为原料，采用激光粉末床熔融（Laser powder bed fusion, LPBF）制备了钨镍合金试样。研究了不同线能量密度的钨镍合金试样的相对密度、显微组织及显微硬度。结果表明：钨镍合金试样的缺陷主要为不规则孔隙，不存在明显可见的裂纹缺陷，且提高线能量密度能够明显减少缺陷。当线能量密度为1.5J/mm时，钨镍合金试样相对密度达98.04%。LPBF制备的钨镍合金试样的显微组织主要由W单质相和Ni-W基体相组成，并伴有大量细小的枝/颗粒状钨晶粒。试样的显微硬度高达529.83HV0.5，且基本不受线能量密度的影响。

Abstract:

The W-Ni alloy specimens were prepared by laser powder bed fusion (LPBF) using 93W-7Ni pre-mixed powder feedstock. The influence of different linear energy densities (LEDs) on relative density, microstructure and microhardness of LPBFed W-Ni alloy specimens. The results show that the defects of the W-Ni alloy specimens are mainly irregular pores with no obvious cracks and the irregular pores can be reduced by increasing the LED. The W-Ni alloy specimens with a maximum relative density of 98.04% can be prepared by using LED of 1.5J/mm. The microstructure of LPBFed W-Ni alloy specimens is mainly composed of W particles and Ni-W matrix phase, accompanied by a large number of fine dendritic/granular W grains. The LPBFed W-Ni specimens have high microhardness with a maximum of 529.83HV0.5, which was not significantly influenced by LED.