PVD涂层刀具高速铣削CoCrMo合金的性能研究

目的为了提高涂层硬质合金刀具的切削性能,研究了物理气相沉积PVD法制备的涂层硬质合金铣刀在高速干式环境下的铣削性能。方法采用阴极电弧技术制备了TiN、TiAlN以及TiAlSiN涂层硬质合金铣刀刀头,通过一同沉积涂层的硬质合金圆片,间接测量得出涂层的显微硬度、厚度和平均摩擦系数,并以CoCrMo合金为切削对象,进行了PVD涂层与无涂层刀具高速铣削下的对比试验。结果TiAlSiN显微硬度最高达3800HV,摩擦系数达0.3,TiAlN涂层平均膜厚为2μm,间接测得TiN、TiAlN以及TiAlSiN涂层的结合力依次为60、58、42N。在三者的切削性能中,TiAlSiN涂层的切削性能比TiAlN和TiN涂层的好,同等切削参数时,TiN刀具的高速铣削时间最短,TiAlSiN涂层的平均磨损值为0.1895,TiN的平均磨损值为0.3047。结论涂层中添加Al、Si,极大地提高了刀具的使用性能,改善了刀具切削过程中的耐磨性、红硬性,极大地延长了刀具的使用寿命。TiAlSiN涂层的硬度高,耐磨损性好,切削性能好,适合高速铣削加工。

Performance of PVD-coated Tool in High Speed Milling of CoCrMo Alloy

The work aims to improve cutting performance of coated carbide-tipped alloy cutters by studying milling performance of physical vapor deposition (PVD) coated carbide-tipped alloy cutters in at high speed and dry environment.TiN,TiAlN and TiAlSiN coated carbide-tipped alloy cutter heads were prepared on surfaces of carbide substrates by cathode arc plasma method.Microhardness,thickness and average friction coefficient were determined by indirect measurement of the cemented carbide disks deposited together with the coating system.A comparative test was performed to CoCrMo alloy at high-speed milling between PVD coatings and uncoated tools.The mechanical properties of the coating obtained were as follows,TiAlSiN micro hardness was up to 3800HV,friction coefficient 0.3,average thickness of TiAlN coating 2 μm,and adhesive force of TiN,TiAlN and TiAlSiN coatings indirectly measured 60,58 and 42 N.TiAlSiN coating exhibited better cutting performance than that of TiN and TiAlN coatings,the high-speed cutting duration of TiN tool was the shortest provided with the same cutting parameters.The average attrition value of TiAlSiN was 0.1895,and TiN 0.3047.The addition of Al and Si to the coating greatly increases the usability of cutters,enhances wear resistance and red hardness during milling,greatly extends the their service life,which provides higher application value for high-speed cutting environment and cutters selection.TiAlSiN coatings of high hardness,good abrasion resistance and the best cutting performance are applicable to high-speed milling.