电爆喷涂制备管内多孔涂层及其形成机理  

Porous coatings in tube sprayed by electrical explosion and its formation mechanism

作　　者：李旺根 朱亮[1,2] 张爱华[2] 周辉[1,2] 杨浙 LI Wanggen;ZHU Liang;ZHANG Aihua;ZHOU Hui;YANG Zhe(State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals,Lanzhou University of Technology,Lanzhou 730050,China;School of Electrical and Information Engineering,Lanzhou University of Technology,Lanzhou 730050,China)

机构地区：[1]兰州理工大学省部共建有色金属先进加工与再利用国家重点实验室,兰州730050 [2]兰州理工大学电气工程与信息工程学院,兰州730050

出　　处：《材料工程》2023年第4期151-158,共8页Journal of Materials Engineering

基　　金：国家自然科学基金资助项目(51765038)。

摘　　要：管内多孔涂层是增强传热性能和提高换热效率的有效途径。采用电爆喷涂制备管内多孔涂层,研究0.5 mm铜丝在不同初始电压下涂层的表面形貌、粗糙度和孔隙分布,并通过沉积能量和爆炸产物讨论微结构涂层的形成机理。结果表明:改变初始电压可以得到不同微观形貌的涂层。初始电压为14.0 kV时,得到最优多孔涂层,形成由小颗粒堆积而成的多孔结构,其表面积是未喷涂涂层管的4.47倍,孔隙率高达57.8%;15.2 kV时,由小熔池凝固后形成均匀的圆形多孔涂层,孔隙率为40.3%。涂层的形成主要取决于不同电压下爆炸时铜丝沉积的能量,它作为喷涂粒子的热动条件,决定了喷涂粒子的能量和粒径大小,不同状态的喷涂粒子与基管表面碰撞后或颗粒堆积或形成熔池,最终导致涂层微观形貌的差异。To produce the porous coating on the inner wall of the pipe is an effective way to enhance heat transfer performance and improve heat exchange efficiency.The electric explosion spraying method was employed to produce the porous coating on the inner wall of the pipe.The surface morphology,roughness and pore distribution of the coating under different initial voltages were studied.The mechanism for the formation of the coating was investigated by the deposition energy and explosive products explained.The results indicate that the initial voltage of the electric explosion spraying influences the microstructure of coating.The optimal porous coating can be obtained when the initial voltage of the electric explosion spraying is 14.0 kV.The optimal porous coating is formed by the accumulation of the small particles.Moreover,the optimal porous coating is obtained,the surface area is 4.47 times that of the uncoated pipe and the porosity of the ideal coating is 57.8%.The uniform round porous coating is formed,when the initial voltage of the electric explosion spraying is 15.2 kV.The porosity of those coating is 40.3%.The formation of the coating depends on the energy deposited on the copper wire during the explosion.The energy deposited on the copper wire acts as the thermodynamic condition for the sprayed particles,determines the energy and particle size of the sprayed particles and the states of the sprayed particles collide with the surface of the base tube or the particles accumulate or form a molten pool.Finally,it influences the microscopic morphology of the coating.

关 键 词：管内喷涂 电爆喷涂 铜多孔涂层 能量沉积 

分 类 号：TG174.44[金属学及工艺—金属表面处理]