摘要: |
研究了电子束选区熔化成形技术中粉末预热工艺对Ti-6Al-4V合金粉末在高能高速电子束作用下抗溃散性能的影响,并对该粉末进行了三维零件成形试验以验证粉末预热在实际成形中的作用。粉末抗溃散试验结果表明,对粉末进行预热可以明显提高粉末在一定电子束束流下的抗溃散临界扫描速度,增强其抗溃散性能;钛合金粉末的三维成形试验结果表明,粉末预热能够有效地改善成形层表面的"边缘缺陷"和"结球缺陷",提高表面质量,降低层厚;成形件显微组织观察结果表明,预热对层间结合情况有明显改善。 |
关键词: 电子束选区熔化 预热 钛合金粉末 快速制造 |
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基金项目:国家自然科学基金资助项目(200475015);中国博士后科学基金资助项目(20070420331) |
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Effects of powder preheating in electron beam selective melting process |
HAN Jiandong, LIN Feng, QI Haibo, YANG Li
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Key Laboratory for Advanced Materials Processing Technology of Ministry of Education, Department of Mechanical Engineering, Tsinghua University, Beijing 100084, China
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Abstract: |
The influence of pre-heating on resistance to pushing-away phenomena of Ti-6Al-4V alloy powder in electron beam selective melting process was investigated.Three dimensional parts are formed using Ti-6Al-4V alloy powder to study the effects of pre-heating.Results indicate that pre-heating process can increase the antipushing-away critical scanning speed, and improve the anti-pushingaway capacity of the powder.Meanwhile, pre-heating process can diminish "exterior scar" and "balling" phenomenon, keep the layer thin, and get better fusion between layers. |
Key words: electron beam selective melting pre-heating titanium alloy rapid manufacturing |