摘要
针对新型铁颗粒增强型氧化铝陶瓷涂层在激光熔覆原位制造过程中的热应力对涂层质量的严重影响,研究了激光诱导反应条件下钛合金表面原位制备单道复合涂层过程中的热力问题。采用代表体积元方法仿真计算该新型涂层的热力学参数。利用生死单元法与内部生热热源相结合的方法建立了激光诱导铝热反应热源模型,分析了不同工艺参数组合下涂层构件热应力分布规律。结果表明:热应力主要集中在涂层及其与基板的结合面处,涂层上沿熔覆方向的拉应力是导致涂层出现横向裂纹的主要原因。由于激光诱导铝热反应,涂层的裂纹以及残余应力随着激光功率和激光扫描速度的增加而增加。在激光功率600 W、扫描速度2 mm/s时,涂层裂纹最少;在扫描速度5 mm/s、激光功率300 W时,残余应力最小。
Considering the significant influence of thermal stress on the coating quality during the in situ fabrication of new iron particlereinforced alumina coating by laser melting,we investigated the thermal stress of a singlepass composite alumina coating on the surface of titanium alloy in this study.The representative volume element method was used to simulate and calculate the thermodynamic parameters of the new coating.The heat source model of the laserinduced thermal reaction heat was established using a combination of the rawdead cell method and internal rawdead heat source.The thermal stress distribution pattern of the coating components at the end of the cladding under different combinations of process parameters was calculated and analyzed.The results indicate that the thermal stresses are primarily concentrated in the coating and its bonding surface with the substrate and the tensile stresses on the coating along the melting direction are the main causes of transverse cracks in the coating.Owing to the laserinduced thermal reaction,the coating cracks increase with laser power and laser scanning speed.At 600 W laser power,the coating has the lowest number of cracks when the scanning speed is 2 mm/s.Moreover,at a scanning speed of 5 mm/s,the coating has the lowest residual stresses when the laser power is 300 W.
作者
张玉燕
方威
李晨
温银堂
Zhang Yuyan;Fang Wei;Li Chen;Wen Yintang(School of Electrical Engineering,Yanshan University,Qinhuangdao 066004,Hebei,China;Key Laboratory of Measurement Technology and Instrumentation of Hebei Province,Qinhuangdao 066004,Hebei,China)
出处
《激光与光电子学进展》
CSCD
北大核心
2023年第9期475-483,共9页
Laser & Optoelectronics Progress
基金
河北省科技计划项目(20312202D,216Z1704G)。
关键词
激光技术
激光熔覆
激光诱导铝热反应
复合涂层
数值模拟
热应力
laser technique
laser cladding
laserinduced thermite reaction
composite coating
numerical simulation
thermal stress
