激光熔覆工艺理论与试验研究  

Process Theory and Experimental Study on Laser Cladding

作　　者：刘继常[1] 

机构地区：[1]湖南大学先进成形与表面工程研究所,湖南长沙410082

出　　处：《电加工与模具》2014年第4期46-53,共8页Electromachining & Mould

基　　金：国家自然科学基金资助项目(51075134)

摘　　要：通过理论和试验研究了激光熔覆过程中粉末流对激光功率的衰减、激光熔覆所需的激光功率及形成熔池的宽度、形貌、熔覆带横截面轮廓等。试验结果发现:在激光熔覆过程中,粉末对激光功率的衰减程度取决于送粉率、气流速度、激光束、粉末流的发散角、腰斑的位置与直径、粉末颗粒直径和激光束穿过粉末流的深度;激光功率下限值与光斑直径、扫描速度及材料熔点等热物理特性有关;在一定的简化条件下,激光单道熔覆形成的熔池宽度是工艺参数和材料特性的函数,较低功率的激光在基板上熔覆时,熔覆带横截面轮廓上各点的高度由粉末浓度分布及熔池内相应点处于液态的时间决定。Attenuation of powder flow on laser power,laser power and width,appearance,cross section outline of cladding zone required by laser cladding are studied in the theory and experiment. The experimental results show that in the caurse of laser cladding,degree of powder attenuation on laser power depend on the powder feeding efficiency, air flow rate, scattered angle of laser beam and powder flow, position and diameter of waist spot, powder diameter, depth of laser beam shot into powder flow. The lower limit volue of laser power relate to rot physical natures,such as the spot diameter,the scanning rate and the melting point of material. Under the certain simplified condition, molten width by laser single way cladding is function of the process parameter and the material characteristics. Cladding by lower laser power ,height of each points on cross section outline of cladding zone depend on the distribution of powder consistency and time placed in liquid state on corresponding points of molten.

关 键 词：激光熔覆 激光功率 衰减 熔池 熔覆带横截面轮廓 

分 类 号：TG665[金属学及工艺—金属切削加工及机床]