(1. 湖南科技大學 高功效輕合金構(gòu)件成形技術(shù)及耐損傷性能評價湖南省工程研究中心，湘潭 411201；
2. 中南大學 輕質(zhì)高強結(jié)構(gòu)材料國家級重點實驗室，長沙 410083；
3. 湖南云箭集團有限公司，長沙 410100)
摘 要: 為提高激光粉末沉積(LPD)制備AlSi10Mg合金的致密度，利用田口方法進行了激光粉末沉積AlSi10Mg合金實驗設(shè)計，研究了激光能量密度對AlSi10Mg合金致密度的影響，獲得了LPD制備高致密度AlSi10Mg合金的能量密度閾值范圍。采用掃描電子顯微鏡(SEM)分析了氧化對激光粉末沉積AlSi10Mg合金致密化的影響，并揭示了LPD制備AlSi10Mg合金的致密化機制。結(jié)果表明：激光能量密度在120~140 J/mm3之間時，可以獲得高致密的AlSi10Mg合金，致密度在98%以上；氧化膜的存在將降低AlSi10Mg熔液在已沉積層表面的潤濕性，熔池內(nèi)AlSi10Mg熔液不能完全鋪展開，導致形成孔洞等缺陷；高激光能量密度可破碎已沉積在AlSi10Mg層表面的氧化膜，使AlSi10Mg熔液能夠在已沉積層表面完全鋪展。
關(guān)鍵字: 增材制造；激光粉末沉積；AlSi10Mg；工藝參數(shù)；致密化；氧化
（1. Hunan Engineering Research Center of Forming Technology and Damage Resistance Evaluation for High Efficiency Light Alloy Components, Hunan University of Science and Technology, Xiangtan 411201, China;
2. National Key Laboratory of Science and Technology for High-strength Structural Materials, Central South University, Changsha 410083, China;
3. Hunan Vanguard Group Co., Ltd., Changsha 410100, China）
Abstract:To improve the densification of AlSi10Mg alloy fabricated by laser powder deposition (LPD), the Taguchi method for the experimental design of laser powder deposition of AlSi10Mg alloy was carried out, the effect of laser energy density on densification of AlSi10Mg alloy was investigated. The threshold range of energy density of high density AlSi10Mg alloy prepared by LPD was obtained. The effect of oxidation on the densification of the LPD AlSi10Mg alloy was analyzed by scanning electron microscope (SEM), and the densification mechanism of AlSi10Mg alloy prepared by LPD was revealed. The results show that high densification AlSi10Mg alloy can be obtained when the laser energy density was between 120 J/mm3 and 140 J/mm3, of which the densification of LPD AlSi10Mg alloy was more than 98%. The existence of oxide film will reduce the wettability of AlSi10Mg melt on the surface of deposited layer, and the AlSi10Mg melt in the molten pool cannot be fully spread, resulting in the formation of holes and other defects. High laser energy density can break the oxide film on the surface of the deposited AlSi10Mg layer, so that the AlSi10Mg melt can be fully spread on the surface of the deposited layer.
Key words: additive manufacturing; laser powder deposition; AlSi10Mg; process parameter; densification; oxidation
