激光增材制造(3D打印)制备钛合金的微观组织研究

Study on the Microstructure of Ti6Al4V Alloy Prepared by Laser Additive Manufacturing(3D Printing)

Ti6Al4V合金作为医用人工关节材料,具有生物相容性好、综合力学性能优异、耐腐蚀能力强等优点,但现有的制备技术制约了其在生物临床医学应用方面的推广和应用。采用激光增材制造(3D打印)技术制备Ti6Al4V合金,并对其微观组织演变规律进行了研究。研究结果表明,多孔Ti6Al4V合金的微观组织由贯穿多个熔覆层且呈外延生长的粗大柱状晶组成,柱状晶的生长方向沿着堆积层的方向生长,由于温度梯度的影响,远离基材区域的晶粒尺寸大于靠近基材区域的晶粒尺寸,原始柱状晶的内部微观组织由细针状"相马氏体组成。

As the medical artificial joint material, Ti6Al4V alloy possesses the advantages of excellent biocompatibility and comprehensive mechanical property , also has excellent synthetic property, but its promotion in biomedical applications is constrained by the current preparation process. Laser additive manufacturing （3D printing） technology is used to fabricate the Ti6Al4V alloy materials. The microstructure of porous Ti6Al4V alloy grows through the building directions of cladding layer and changes into coarse columnar crystal epitaxial growth, and the growth direction of the columnar grains along the layer building directions. Due to the influence of temperature gradient, grain size far away from the substrate area is larger than the grain size near the substrate region, and microstructure of the original columnar crystal is composed of the fine acicular alpha phase coated at martensites.