摘要
为了改善切削刀具表面常用的TiAlN涂层的性能,采用阴极弧蒸发方法在硬质合金、低合金钢、刚玉片和钨基体上制备了TiAlN和TiAlNbN涂层,借助差示扫描量热仪(DSC)、扫描电子显微镜(SEM)、X射线能量色散谱仪(EDX)、X射线衍射仪(XRD)和纳米压痕仪研究了Nb添加对TiAlN涂层的结构、力学及热性能的影响.结果表明:制备的Ti0.46Al0.54N、Ti0.40Al0.53Nb0.07N和Ti0.34Al0.52Nb0.14N涂层均为亚稳的面心立方结构,其硬度分别为30.1±0.4 GPa、29.7±0.4 GPa和29.6±0.7 GPa;Nb添加提高了涂层的H3/E2值,表明其韧性得到改善;Nb添加抑制了TiAlN涂层热分解过程中的调幅分解和六方相AlN的形成,从而改善其热稳定性;另外,在900℃氧化10h后,Ti0.46Al0.54N涂层已完全氧化,而Ti0.40Al0.53Nb0.07N和Ti0.34Al0.52Nb014N涂层的氧化层厚度分别为0.91μm和0.67μm.
The effect of Nb-addition on the structure,mechanical and thermal properties of TiAlN coating deposited oncemented carbide,low-alloy steel,polycrystalline Al2O3 and tungsten substrates is investigated using differential scanningcalorimetry,scanning electron microscopy,energy dispersive X-ray spectroscopy,X-ray diffraction and nano-indentation.Inorder to optimize the propertiy of TiAlN coating,Ti0.46Al0.54N,Ti0.40Al0.53Nb0.07N and Ti0.34Al0.52Nb0.14N coatings deposited bycathodic arc evaporation behave metastable face-centered cubic structure,and hardness values of 30.1±0.4 GPa,29.7±0.4GPa and 29.6±0.7 GPa,respectively.Alloying with Nb into TiAlN coating increases the H3/E2ratio and toughness.Thethermal stability of TiAlN coating is improved by retarding the spinodal decomposition and w-AlN precipitation.After 10h oxidation at 900℃,the oxide scales of Ti0.40Al0.53Nb0.07N and Ti0.34Al0.52Nb0.14N coatings are 0.91 and 0.67μm,while theTi0.46Al0.54N coating has been completely oxidized.
作者
刘慧君
吴明晶
王社权
Liu Huijun;Wu Mingjing;Wang shequan(State Key Laboratory of Powder Metallurgy,Central South University,Changsha Hunan 410083,China;Zhuzhou Cemented Carbide Cutting Tools Company Limited,Zhuzhou Hunan 412007,China)
出处
《硬质合金》
CAS
2019年第3期184-191,共8页
Cemented Carbides
