PVD涂层高速钢微钻用于铝合金钻削性能研究

Performance research of PVD coating high speed steel micro drill for drilling aluminum alloy

为了提高高速钢微细钻头的钻削质量,研究了物理气相沉积(PVD)涂层高速钢微细钻头在高速干式环境下钻削铝合金时的钻削性能。应用PVD离子镀技术在直径0.2 mm的高速钢微细钻头上制备Ti Al Si N、DLC、Ti N和Al Ti N 4种涂层,并通过同时沉积涂层的高速钢圆盘间接测量得到涂层的显微硬度、厚度和平均摩擦系数。以6061铝合金为被加工零件对涂层的实际加工性能进行了试验测试,得到了已钻取孔的表面形貌、直径和角磨损量。通过VHM-I04显微硬度计在0.49 N下测定,DLC涂层微钻的显微硬度为2 800,摩擦系数为0.05,钻削效果在所有涂层微钻和未涂层微钻中最好。因与高速钢基体结合差,导致Ti Al Si N涂层容易脱落、微钻磨损快,故Ti Al Si N涂层不适合沉积在微钻表面。

In order to improve the drilling quality of high speed steel micro drills , the drilling performance of the physical vapor deposition （ PVD） coating of high speed steel micro drill at high speed is studied in a dry environment .Four kinds of coating TiAlSiN ,DLC,TiN and AlTiN are coated by PVD ion plating technology on high speed steel micro drills of 0.2 mm diameter.In order to measure the micro hardness ,thickness and the average friction coefficient of each coating ,4 high-speed steel discs are prepared ,and each has a homologous coating of the 4 high speed steel micro drills .The processing performance of the coatings is tested in experiments carrying out on 6061 aluminum alloy parts,and the surface morphology ,diameter variation and corner wear are obtained .By using the VHM-I04 microhardness tester of 0.49 N,the microhardness of DLC coating micro drill is 2 800,its friction＆amp;nbsp;coefficient is 0.05,and its drilling performance is the best of the four coating micro drills and one no coating micro drill .TiAlSiN coating falls off easily from the substrate and wears fast due to its poor adhesion strength with high speed steel ,and TiAlSiN coating is not suitable for micro drills .