摘要
采用超音速微粒轰击技术在激光增材TC4表面制备了纳米梯度强化层,并采用X射线衍射(XRD)、光学显微镜(OM)、扫描电子显微镜(SEM)、维氏硬度计和磨损试验机对不同处理时间的纳米梯度强化层微观结构演变和力学性能进行了测试。结果表明,经超音速微粒轰击处理后,TC4合金在一定范围内形成梯度结构的塑性变形区,其表面形成纳米晶。随轰击时间的增加,变形区厚度增大、纳米晶粒尺寸逐渐减小,轰击360 s样品变形层厚度为500μm,晶粒尺寸可达10.4 nm。随着晶粒细化和塑性变形的加剧,组织中α′相含量增多,由细晶强化和相变强化共同作用,激光增材TC4合金硬度显著增大。当轰击时间为360 s时,样品的最高硬度为735.8 HV0.1,较未处理激光增材TC4合金提高约23%,表现出更优异的摩擦磨损性能,其磨损方式由以粘着磨损为主逐渐变为以磨粒磨损为主。
Nano-gradient reinforced layer was prepared on a laser additive manufactured TC4 alloy using supersonic fine particles bombarding process(SFPB).The microstructure evolution and mechanical properties of the nano-gradient reinforced layers under different durations bombarding treatment were analyzed through X-ray diffraction(XRD),optical microscopy(OM),scanning electron microscopy(SEM),as well as Vickers test and wear test,respectively.The results showed that a deformed layer with a gradient microstructure was produced in a certain range,in which the nanograins is formed on surface of TC4 alloy.Moreover,the thickness of the deformation zone increased and the size of the nanograin decreased gradually with the increase of bombardment duration.The thickness of the deformation layer was 500μm and the grain size may reach 10.4 nm when the bombardment duration was 360 s.Then,the content ofα′increased with the intensification of grain refinement and plastic deformation,the deformed layer exhibited a much higher hardness than the untreated samples.When the bombardment duration was 360 s,the maximum hardness of the sample was 735.8 HV0.1,which was about 23%higher than that of the untreated laser additive manufactured TC4 alloy.Thus,the friction and wear properties of laser additive manufactured TC4 alloy was markedly improved by SFPB treatment,and the wear mode of the laser additive manufactured TC4 alloy changes from adhesive wear to abrasive wear after SFPB.
作者
董美伶
金国
王超会
林蔚
崔秀芳
DONG Meiling;JIN Guo;WANG Chaohui;LIN Wei;CUI Xiufang(College of Materials Science and Engineering,Qiqihar University,Qiqihar 161006,China;College of Material Science and Chemical Engineering,Harbin Engineering University,Harbin 150001,China)
出处
《有色金属工程》
CAS
北大核心
2021年第8期22-28,共7页
Nonferrous Metals Engineering
基金
国家自然科学基金资助项目(51775127)
黑龙江省科学基金(E2018020)
黑龙江省省属高等学校基本科研业务费科研项目,青年创新人才项目(135409202)。
关键词
增材制造
TC4合金
纳米晶
摩擦学性能
additive manufacturing
TC4 alloy
nanocrystalline
tribological property
