激光功率对205B铝合金激光-CMT复合增材组织及性能的影响  

Effect of Laser Power on Microstructure and Properties of 205B Aluminum Alloy Laser-CMT Composite Additive Manufacturing

作　　者：吕蒙[1,2] 张嘉 郭海伟 杨丰豪 LYU Meng;ZHANG Jia;GUO Haiwei;YANG Fenghao(College of Mechanical and Electrical Engineering,Zhengzhou Railway Vocational and Technical College,Zhengzhou 450000,China;Zhengzhou Key Laboratory of Advanced Functional Materials,Zhengzhou 450000,China;Zhengzhou Nonferrous Metals Research Institute Co.,Ltd.,of CHALCO,Zhengzhou 450000,China)

机构地区：[1]郑州铁路职业技术学院机电工程学院,郑州450000 [2]郑州市先进功能材料重点实验室,郑州450000 [3]中铝郑州有色金属研究院有限公司,郑州450000

出　　处：《精密成形工程》2024年第8期111-120,共10页Journal of Netshape Forming Engineering

基　　金：河南省科技攻关项目(232102231011);河南省教育厅高等学校重点科研项目(23B430016);河南省科技攻关项目(222102230025)。

摘　　要：目的针对传统增材技术造成的205B铝合金组织均匀性差、气孔率高、强度低等问题,选用激光-电弧(CMT)复合增材技术为研究方法,探究激光功率对其组织均匀性和性能的影响规律。方法采用激光-电弧(CMT)复合增材技术实现了205B铝合金增材成形件的良好成形,并利用现代分析技术对材料的宏微观组织形貌、第二相分布、气孔、物相组成、显微硬度及拉伸强度进行表征。结果成形件中部区域呈现“凹弧形”层状结构特征且存在一定程度的组织不均匀性和各类气孔。激光功率对材料层间和层内宏微观组织及第二相分布有显著影响,当激光功率增加至1800W及以上时,层间“细晶带”特征明显且柱状晶组织逐渐消失。当激光功率为1600 W时,材料获得了最低的气孔率(0.85%),平均气孔直径为25.58μm,平均气孔数量为32。材料具有典型的拉伸强度各向异性,当激光功率为1600 W时,材料的横向拉伸强度和纵向拉伸强度均获得最大值,分别为265.65MP和235.75MPa。结论通过调节激光功率能够在一定程度上解决材料组织不均匀的问题并减小气孔率,从而提高了成形件的力学性能。The work aims to explore the effect of laser power on the microstructure uniformity and properties of 205 B alu-minum alloy with laser-arc(CMT)composite additive technology as the research method to deal with problems of poor micro-structure uniformity,high porosity and low strength caused by traditional additive technology of 205 B aluminum alloy.The la-ser-arc(CMT)composite additive technology was used to achieve good forming of 205B aluminum alloy additively formed parts,and modern analytical techniques were used to characterize the macroscopic organization and morphology of the material,the second direction distribution,the porosity,the composition of the physical phases,the microhardness and the tensile strength.The central region of the molded part showed a“concave-arc”layer structure with a certain degree of tissue inhomogeneity and various types of porosity.The laser power had a significant effect on the interlayer and intralayer macro-morphology and the distribution of the second phase.As the laser power increased to 1800 W and above,the interlayer“fine grained band”was ob-vious and the columnar crystal organization disappeared gradually.The lowest porosity(0.85%),average pore diameter(25.58μm),and average number of pores(32)were obtained at a laser power of 1600 W.The material possesses typical tensile strength anisotropy,and the maximum values of transverse tensile strength and longitudinal tensile strength of the material were obtained at a laser power of 1600 W,which were 265.65 MP and 235.75 MPa,respectively.By adjusting the laser power,it is possible to improve the problem of material organization inhomogeneity and reduce the porosity to a certain extent,thus im-proving its mechanical properties.

关 键 词：205B铝合金 激光-CMT复合增材 激光功率 细晶带 各向异性 

分 类 号：TG457.14[金属学及工艺—焊接]