本文關鍵詞： IN鎳基超合金 變能量激光選區(qū)熔化 激光成形 致密度 表面質量 高溫機械性能　出處：《光學精密工程》2015年06期 　論文類型：期刊論文

【摘要】：開展了基于激光選區(qū)熔化技術對IN718鎳基超合金直接激光熔化成形的研究。將零件分為心部與輪廓區(qū),通過改變激光線輸入量進行選區(qū)熔化研究。首先,建立熔池內燒結的數值模型,改變激光線輸入量,獲得了激光線輸入量對零件致密度的影響規(guī)律并觀察了成形體中的組織生長。然后,增加輪廓部位掃描,改變激光線輸入量與掃描順序,獲得其對零件表面質量的影響規(guī)律。最后,通過優(yōu)化熱處理工藝提高零件高溫拉伸強度和高溫持久性能。試驗結果表明,在激光線輸入量為300J/m時,成形體致密度最高,為98.9%,成形體沿層間方向組織為樹枝晶加等軸晶,在層內方向組織為等軸晶。采用心部+后輪廓掃描的方式,輪廓激光線輸入量為100J/m時表面質量最優(yōu),粗糙度為3.1μm。對成形體采用1 065℃固溶+雙時效的熱處理可以獲得最佳高溫性能組合,高溫拉伸強度為1 356MPa,高溫持久時間為34h。結果顯示,通過激光選區(qū)熔化制作IN718鎳基超合金可以滿足航空結構件對致密度、表面質量和高溫性能要求。
[Abstract]:The direct laser melting forming of IN718 nickel-based superalloy is studied based on laser selective melting technology. The parts are divided into the core and the contour region, and the selective melting is studied by changing the input amount of the laser line. The numerical model of sintering in the molten pool is established. The influence of laser line input on the density of the parts is obtained by changing the input amount of laser line, and the microstructure growth in the shape is observed. Then, the scanning of the profile is added. The influence of laser line input and scanning sequence on the surface quality of the parts is obtained. Finally, the tensile strength at high temperature and the high temperature rupture property of the parts are improved by optimizing the heat treatment process. The experimental results show that, When the input of the laser line is 300J / m, the density of the shape is 98.9, the shape is dendritic and equiaxed along the interlayer direction, and the equiaxed crystal is formed in the inner layer. The surface quality is the best and the roughness is 3.1 渭 m when the input amount of the contour laser line is 100 J / m. The best combination of high temperature properties can be obtained by heat treatment of solid solution double aging at 1 065 鈩，

本文編號：1538193