Tool Wear of Aluminum/Chromium/Tungsten-Based-Coated Cemented Carbide in Cutting Hardened Steel

Abstract

An aluminum/chromium based coating film, called (Al,Cr)N coating film, has been developed. This coating film has a slightly more inferior critical scratch load and micro-hardness. Therefore, to improve both the scratch strength and micro-hardness of the (Al,Cr)N coating film, the cathode material of an alumi-num/chromium/tungsten target was used in adding the tungsten (W) to the cathode material of the alumi-num/chromium target. To clarify the effectiveness of the aluminum/chromium/tungsten-based coating film, we measured the thickness, micro-hardness and critical scratch strength of aluminum/chromium/tungsten-based coating film formed on the surface of a substrate of cemented carbide ISO K10 formed by the arc ion plating process. The hardened steel ASTM D2 was turned with the (Al,Cr,W)N, (Al,Cr,W)(C,N), (Al,Cr)N and the (Ti,Al)N coated cemented carbide tools. The tool wear of the coated cemented carbide tools was ex-perimentally investigated. The following results were obtained: (1) The micro-hardness of the (Al,Cr,W)N or (Al,Cr,W)(C,N), (Al,Cr)N coating film was 3110 HV0.25N or 3080 HV0.25N, respectively. (2) The critical scratch load of the (Al,Cr,W)(C,N) coating film was 123 N, which was much higher than that of the (Al,Cr)N or (Ti,Al)N coating film. (3) In cutting the hardened steel using (Al,Cr,W)(C,N) and (Ti,Al)N coated carbide tools, the wear progress of the (Al,Cr,W)(C,N) coated carbide tool was almost equivalent to that of the (Ti,Al)N coated carbide tool. The above results clarify that the aluminum/chromium/tungsten-based coating film, which is a new type of coating film, has both high hardness and good adhesive strength, and can be used as a coating film of WC-Co cemented carbide cutting tools.

Tool Wear of (Al,Cr,W)/(Al,Cr,W,Si)-Based-Coated Cemented Carbide Tools in Cutting of Hardened Steel

“…The incorporation of Si [9], Y [9], W [10], Fe [11], Zr [12] or Ti [13] into (Cr, Al) N was reported. In cutting hardened steel [14] or sintered steel [15], the wear resistance of (Al, Cr, W) N coated tools with W added to (Al, Cr) N coated tools was improved. The wear resistance of (Al, Cr, W)(C,N) coated tools with C added to (Al,Cr,W) N coated tools was improved [14]- [17].…”

“…In cutting hardened steel [14] or sintered steel [15], the wear resistance of (Al, Cr, W) N coated tools with W added to (Al, Cr) N coated tools was improved. The wear resistance of (Al, Cr, W)(C,N) coated tools with C added to (Al,Cr,W) N coated tools was improved [14]- [17]. Furthermore, the wear resistance of (Al, Cr, W,Si)N coated tools with Si added to (Al, Cr,W) N coated tools was improved [18].…”

Wear Mechanism of Multilayer AlCrWN/AlCrWSiN-coatings on Cemented Carbide Tools Prepared by Arc Ion Plating in Dry Cutting of Hardened Sintered Steel

“…However, our study results show that the critical scratch load of the AlCrN coating film, which is the value measured by the scratch test, is 77 N and the micro-hardness is 2760 HV 0.25 N . Therefore, in order to improve both the critical scratch load and micro-hardness of the AlCrN coating film, a cathode material of the Al-Cr-W target with tungsten (W) added to the cathode material of the Al-Cr target was used [4]. The Al-Cr-W based coating film has both high hardness and excellent critical scratch load and can be used sufficiently as a coating film of WC-Co cemented carbide cutting tools [4].…”

“…Therefore, in order to improve both the critical scratch load and micro-hardness of the AlCrN coating film, a cathode material of the Al-Cr-W target with tungsten (W) added to the cathode material of the Al-Cr target was used [4]. The Al-Cr-W based coating film has both high hardness and excellent critical scratch load and can be used sufficiently as a coating film of WC-Co cemented carbide cutting tools [4]. Furthermore, the friction between the face of the cutting tool and the chip decreases when W is added [5][6].…”

Wear Mechanism of Multi-layer AlCrWN/AlCrWSiN Coatings on Cemented Carbide Tool Prepared by Arc Ion Plating in Dry Cutting of Sintered Steel

“…Therefore, in order to improve both the scratch strength and the micro-hardness of the AlCrN coating film, cathode material of an Al-Cr-W target was used in adding tungsten (W) to the cathode material of the Al-Cr target. As a result, the scratch strength and the microhardness of the AlCrWN coating film increased to 81 N and 3110 HV 0.25N , respectively [2]. To improve the properties of the coating film, the cathode material of an Al-Cr-W-Si target was used [3][4][5].…”