摘要
利用Ansys有限元软件进行数值模拟并利用光纤激光器进行试验验证。分别采用蔡司显微镜、电化学工作站研究熔凝表面的微观组织和腐蚀行为。结果表明:激光熔凝温度场呈骤热快冷、动态变化的特点,其表面的温度梯度最大,由表及里,温度梯度依次减小。实际测量与数值模拟的熔池深度和熔池宽度的误差均不超过15%,表明温度场数值模型与实际模型相符合。激光熔凝后,稀土镁合金材料表层晶粒细化,其自腐蚀电流密度较母材降低了一个数量级,表明激光熔凝可有效改善稀土镁合金材料表面的耐蚀性。
Numerical simulation was conducted by using Ansys finite element software and the experiment verifications were carried out by fiber laser. The microstructure and corrosion behavior of laser melted surface were characterized by Zeiss microscope and electrochemical workstation respectively. The results show that the characteristics of temperature field in laser surface remelting is sudden heat, fast cooling and dynamic change. The surface temperature gradient is maximum. The temperature gradient decreases gradually from the outside to the inside. The error of the weld pool depth and width measured by actual measuremem and numerical simulation is not more than 15%, which indicates that the numerical model of temperature field is consistent with actual model. After laser surface remelfing, the surface grain of rare earth magnesium alloy is refined and its self corrosion current density reduces by an order of magnitude compared with matrix, which indicates that laser surface remelting can effectively improve the corrosion resistance of surface of rare earth magnesium alloy.
作者
张春燕
杨武
马超
ZHANG Chunyan YANG Wu MA Chao(School of Mechanical Engineering, Jiangsu University of Science and Technology, Zhenjiang 212003, China)
出处
《热加工工艺》
CSCD
北大核心
2017年第2期143-147,154,共6页
Hot Working Technology
关键词
稀土镁合金
耐蚀性
温度场
激光熔凝
rare earth magnesium alloy
corrosion resistance
temperature field
laser surface remelfing （LSM）
