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Hard film such as TiN, is deposited in a high-speed steel and carbide tool surface hardness and wear resistance of the tool can be improved, thereby improving the cutting performance and service life. But with the increasing popularity of CNC machine tools, high-speed cutting has become the mainstream of the machining the TiN films tool difficult to meet the performance requirements. On the other hand, the film alloying, multi-layered and gradient of the composite form can be achieved to improve the performance and service life of hard coatings. Therefore, this paper aims to explore the improvement of the overall performance of the TiN-based composite films by alloying elements and films constitute a change in the form. Multi-arc ion plating technology, the use of two Ti-Al-Zr alloy target and a pure Cr target on the speed steel of W18Cr4V and WC-8% Co cemented carbide two matrix deposited four kinds of Ti-Al- Zr-Cr-N composite hard film, i.e. (Ti, Al, Zr, Cr) N polyhydric film (Ti, Al, Zr) N / (Ti, Al, Zr, Cr) N and CrN / (Ti, Al, Zr, Cr) N multiple bilayers and TiAlZrCr / (Ti, Al, Zr, Cr) N polyhydric gradient film. Using scanning electron microscopy (SEM), laser scanning confocal optical microscopy, electron spectroscopy (EDS) and X-ray diffraction (XRD), four composite membrane composition, morphology, roughness and micro-structure measurement and characterization; microhardness and scratch tester evaluation the four composite hardness of the film and film / substrate binding force; friction and wear tester four composite film at room temperature (15 ° C) and high temperature (500 ° C) under the conditions of wear-resistant characteristics, and the use of SEM observation of the surface morphology of the wear scar; the four composite film was 600 ° C, 700 ° C, 800 ° C and 900 ° C short-time temperature oxidation experiments (4h) and 700 ° C and 800 ° C. (100h) long high-temperature cyclic oxidation experiments and the use of SEM, EDS and XRD observation and analysis of the sample surface oxide film. The study results showed that the obtained four kinds of Ti-Al-Zr-Cr-N composite hard film having a TiN B1-NaCl-type face-centered cubic structure; the four composite membrane component in addition to the-50V bias, remaining partial The reduction was not significantly change; composite film surface is relatively smooth, dense, but there are still many large particles (micro-droplets) and microporous defects, while increasing the bias can be reduced to the surface of the droplet contamination phenomenon surface roughness improved; no obvious defects between the composite film and the substrate, the thin film having a columnar grain structure from the substrate to the surface of the vertical growth; the type of bias, the four composite film has a thickness of about 1 to 1.5 μm, and as the bias increases, the thickness decreases. High-speed steel and cemented carbide substrate on the (Ti, Al, Zr, Cr) N polyhydric film (Al Zr Cr) / (Ti Al Zr Cr) atomic ratio of 0.44 to 0.52 and 0.41 to 0.43, respectively, when its chemotactic at 0.44 and 0.41 hours, the microhardness of the film, respectively, the maximum value 3300HV 0.01 and to 3600HV 0.01 , the film / substrate binding force, respectively, reaches a maximum of 190N and 200N. (Ti, Al, Zr, Cr) N multi-film friction and wear mechanisms are plastic deformation as the main feature of adhesive wear, accompanied by a slight abrasive wear. Under the conditions of room temperature and high temperature wear, the average coefficient of friction between 0.3 and 0.5. The coefficient of friction of the film curve and the wear surface morphology analysis showed that with the deposition bias increases, its wear resistance is improved, and the cemented carbide substrate is slightly better than the abrasion resistance of the film in the high-speed steel substrate. In addition, in a short time under oxidizing conditions, high-speed steel and cemented carbide substrate (Ti, Al, Zr, Cr) N film at 800 ° C and 700 ° C respectively with good high temperature oxidation resistance observed in the XRD patterns to the rutile TiO 2 ; under oxidizing conditions in long, high-speed steel and cemented carbide substrate (Ti, Al, Zr, Cr) N membrane resistance to high temperature cyclic oxidation temperature to 700 ° C and 600 ° C. (Ti, Al, Zr) N / (Ti, Al, Zr, Cr) N polyhydric bilayers having a higher hardness than a single layer of (Ti, Al, Zr, Cr) N film and the film / substrate combination of stronger force. (Ti, Al, Zr) N / (Ti, Al, Zr, Cr) N film (Al Zr Cr) / (Ti Al Zr Cr) atomic ratios of 0.44 and 0.40 when the high-speed steel and carbide substrate , the micro-hardness of the film reached the maximum 3450HV 0.01 and to 4000HV 0.01 , the film / substrate binding force reached the maximum 190N and 200N. At the same time, the (Ti, Al, Zr) N / (Ti, Al, Zr, Cr) N bilayers having a ratio of (Ti, Al, Zr, Cr) N monolayer film better abrasion resistance, at room temperature The average coefficient of friction and high temperature wear in between 0.3 to 0.35. Moreover, the weight gain by oxidation, oxide film on the surface morphology and phase structure analysis showed that the (Ti, Al, Zr) N / (Ti, Al, Zr, Cr) N bilayers having a ratio of (Ti, Al, Zr, , Cr) N monolayer good resistance to high temperature oxidation resistance. CrN / (Ti, Al, Zr, Cr) N polyhydric bilayer membrane having a ratio of (Ti, Al, Zr, Cr) N single-layer film higher, but slightly lower than the (Ti, Al, Zr) n / (Ti, Al, Zr, Cr) N bilayer membrane hardness, while having a ratio of (Ti, Al, Zr, Cr) N monolayer film, and the (Ti, Al, Zr) N / (Ti, Al, Zr, Cr) N bis layer film / substrate adhesion. When the high-speed steel and cemented carbide substrate, CrN / (Ti, Al, Zr, Cr) N film (Al Zr Cr atomic ratio) / (Ti Al Zr Cr) tends to be respectively 0.45 and 0.40 hours, the film microhardness reached the maximum 3400HV 0.01 and to 3900HV 0.01 , the film / substrate binding force reached the maximum 190N and 200N. CrN / (Ti, Al, Zr, Cr) N bilayer membrane having a ratio of (Ti, Al, Zr, Cr) N monolayer film better, but slightly lower than the (Ti, Al, Zr) n / (Ti , Al, Zr, Cr) N bilayers wear-resistant properties, wear under ambient and elevated temperatures when the average coefficient of friction between 0.3 to 0.4 and 0.3 to 0.45 respectively. Moreover, CrN / (Ti, Al, Zr, Cr) N bilayer membrane having a ratio of (Ti, Al, Zr, Cr) N Monolayers others good high temperature oxidation resistance. The cemented carbide substrate under oxidizing conditions in the short-term, CrN / (Ti, Al, Zr, Cr) N film resistance to high temperature oxidation temperature further improve to 800 ° C. TiAlZrCr / (Ti, Al, Zr, Cr) N polyhydric gradient film having a ratio of (Ti, Al, Zr, Cr) N monolayer and (Ti, Al, Zr) N / (Ti, Al, Zr, Cr) N and CRN / (Ti, Al, Zr, Cr) N bilayers higher hardness and stronger film / substrate binding force. Gradient film (Al Zr atomic ratio of Cr) / (Ti Al Zr Cr), respectively, 0.45 and 0.39 when the high-speed steel and cemented carbide substrate, the thin film micro-hardness reaches the maximum 3500HV 0.01 to 4000HV 0.01 , the film / substrate binding force reached the maximum 200N and 200N. At the same time, of TiAlZrCr / (Ti, Al, Zr, Cr) N gradient film having a ratio of (Ti, Al, Zr, Cr) N monolayer and (Ti, Al, Zr) N / (Ti, Al, Zr, Cr) N and CrN / (Ti, Al, Zr, Cr) N bilayers better abrasion resistance, wear under ambient and elevated temperatures when the average coefficient of friction between 0.25 to 0.3 and 0.3 to 0.35, respectively. Moreover, in the short time under oxidizing conditions, on the high-speed steel and carbide two matrix TiAlZrCr / (Ti, Al, Zr, Cr) N gradient film at 800 ℃ has good resistance to high temperature oxidation resistance; long Under oxidizing conditions, the high-speed steel and carbide two substrate TiAlZrCr / (Ti, Al, Zr, Cr) N gradient film resistance to high temperature cyclic oxidation temperature are 700 ° C, and (Ti, Al, Zr, Cr) N monolayer and (Ti, Al, Zr) N / (Ti, Al, Zr, Cr) N and CrN / (Ti, Al, Zr, Cr) N bilayers compared to its high temperature oxidation resistance has been significantly improved.
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