氮气分压对AlCrTiSiN超晶格涂层微观结构及力学性能的影响

超晶格涂层因具有优异的力学性能及抗氧化性能在刀具涂层工业中备受关注。采用多弧离子镀技术在高速钢表面制备了AlCrTiSiN涂层,研究了氮气分压对AlCrTiSiN涂层微观结构及力学性能的影响。利用X射线衍射仪(XRD)、扫描电子显微镜(SEM)和原子力显微镜研究了AlCrTiSiN涂层的微观结构;利用纳米压痕仪、划痕仪和磨损仪研究了AlCrTiSiN涂层的力学性能。结果表明:不同氮气分压的AlCrTiSiN涂层均由(Cr,Al)N相、(Ti,Al)N相和(Cr,Al)2N相以及非晶态的Si相和Si3N4相组成。与氮气分压为4Pa的涂层相比,氮气分压为2或3Pa的涂层具有更高的硬度、抗载荷能力和涂层-基体结合强度,以及更低的摩擦因数及磨损率。此外,45钢和铸铁切削试验表明:AlCrTiSiN涂层刀具较AlCrN涂层刀具有更好的切削性能,无涂层刀具具有最差的切削性能。

Effects of Partial Pressure of N2 on Microstructure and Mechanical Properties of AlCrTiSiN Superlattice Coatings

Superlattice coatings have been paid extensive attention to the cutting tool industry due to their excellent mechanical properties and oxidation resistance. AlCrTiSiN coatings were deposited on the surface of highspeed steels by multiarc ion plating, and the effects of nitrogen partial pressure on the microstructure and mechanical properties of these AlCrTiSiN coatings were investigated. XRD, XPS and SEM were used out to study the microstructure of these superlattice coatings, and nanoindetation test, scratch tester and pinondisk tribotest were employed to measure the mechanical properties of the coating. The results show that the microstructure of the superlattice coatings are composed of (Cr,Al)N phase, (Ti,Al)N phase and (Cr,Al)2N phases as well as amorphous Si and Si3N4 phases. Compared with the superlattice coatings deposited with 4 Pa partial pressure of nitrogen, the superlattice coatings deposited at 2 or 3 Pa present higher hardness, bearing capacity and adhesion strength of the coating to the substrate, as well as lower friction coefficient and wear rate. Additionally, cutting experiments of 45 steel and iron casting show that the tool with AlCrTiSiN coating reveals much higher cutting property than that of the tool with AlCrN coating, and the tool without any coating displays the lowest cutting property.