【激光熔覆金属基复合涂层及颗粒相在熔池中行为的研究】王毛球.pdf

DissertationSubmitted to HuazhongUniversity of Scienceand Technology for theDegree ofDoctorof PhilosophyinEngineering Investigation onMetal-Matrix Composite Coatings Produced by Laser Cladding and Behavior of Particle Phase in the MoltenPool Ph.D.

华中理工大学博士学位论文首次将几种Cu基复合涂层从基体试样上剥离下来,利用四点探针法测量其电阻率。结果发现,几种熔覆层的电阻率都较低,并且与其材料组成密切相关。当熔覆层中Fe含量较高、而Cu含量较低时,其电阻率也较高。熔覆层的电导率在30 IACS 以上,说明都具有较高的导电能力,可见该类材料在导电领域具有良好的应用前景.对纯Cu和Al2O3、Cr2O3、Al以及Fe等组成的混合粉末进行的DSC分析表明,Al2O3、Cr2O并不与Cu发生作用,Al与Cu强烈作用,而Fe则作用较弱。Cu的氧化以及Cu与部分颗粒相反应放热量较多,使得激光熔覆含Cu混合粉末所需最小比能降低。

华中理工大学博士学位论文 conclusion can be drawn that laser cladding processing with mixtures is related to the variety and content of the particle phase,which indicates that the addition of high absorptivityparticlephasessuchasAlzOandCr2Oandlowermeltingpointparticle phasessuch asAl canimprovetheprocessing Them