金属型表面喷涂法和热化学反应法涂层性能  

The Properties of Spraying and Thermochemical Reaction Coating on the Metal Mold Surface

作　　者：李勉[1] 刘建睿[1] 黄卫东[1] 

机构地区：[1]西北工业大学凝固技术国家重点实验室,陕西西安710072

出　　处：《铸造》2014年第6期523-527,共5页Foundry

基　　金：西北工业大学凝固技术国家重点实验室自主研究课题资助(No.29-TP-2009)

摘　　要：以Al2O3、SiO2、低熔点玻璃粉为原料,分别采用喷涂法和热化学反应法在金属型表面形成涂层,对比分析涂层与金属型基体的结合强度、铝合金熔体在涂层面的润湿性以及涂层对铝合金铸件表面粗糙度的影响.结果表明,热化学反应法涂层形成3Al2O3·2SiO2、Al2SiO5新相,涂层与金属型基体结合强度达8.95 MPa,而喷涂法涂层与金属型基体结合强度仅为0.97 MPa;铝合金熔体在热化学反应法涂层和喷涂法涂层表面接触角分别为143.7°和127.5°,对应铸件表面粗糙度值分别为1.817 μm和2.654 μm;连续浇注铝合金后热化学反应法涂层无脱落现象,浇注所得铝合金铸件表面光洁平整,粗糙度（Ra）值为1.0～2.0 μm.The coatings were prepared on metal-mold surface by spraying method and thermo-chemical reaction method with Al2O3,SiO2 and low melting point glass powder.The bonding strength of the coating with metal mold,the wettability of coating with aluminum alloy melt and the influence of coating on the casting surface roughness were analyzed.The results show that the thermochemical reaction method coating formed new phase of 3Al2O3· 2SiO2,Al2SiO5,the bonding strength of the thermochemical reaction method coating with metal mold up to 8.95 MPa,and the bonding strength of the spraying method coating with metal mold is only 0.97 MPa.The contact angle of aluminum alloy melt on thermochemical reaction method coating and spraying coating is 143.7° and 127.5° respectively,and the corresponding surface roughness of castings is 1.817 μm and 2.654 μm.After continuous casting of aluminum alloy,the thermochemical reaction method coating did not fall off,aluminium alloy casting surface is bright,clean and level,the roughness of aluminum alloy castings reaches to a level of Ra 1.0-2.0 μm.

关 键 词：金属型铸造 结合强度 润湿性 铸件表面粗糙度 

分 类 号：TG174.4[金属学及工艺—金属表面处理]