The effect of substrate temperature of (Ti,A1)N coating on AISI 304L stainless steel and high speed steel using physical vapor deposition (PVD) method

Abstract

The purpose of (Ti,Al)N coating was to provide adherent coating on steel substrates to improve mechanical properties of steel tools in industrial applications. The effect of substrate temperature of physical vapour deposition (PVD) was an important parameter to study which affect the adhesion strength of (Ti,Al)N coating on alloy steel substrates. In this research, two types of substrates were chosen: AISI 304L stainless steel and high speed steel (HSS). The coating was deposited on both substrates at four different substrate temperatures which are 200oC, 240oC, 300oC, and 400oC for 90 minutes deposition time with 200 watt DC power, gas flow rate was maintained at ratio of 10 sccm N2 : 20 sccm Ar, and 10 mTorr working pressure was used using a pure TiAl target with 50 wt% Ti : 50 wt% Al ratio. The coating morphology was observed as columnar type structure and the surface roughness was decreased with substrate temperatures. From the adhesion test results it shows that the adhesion strength of (Ti,Al)N coating was increased with substrate temperature for both 304L stainless steel and HSS but, the deposition rate of coating was decreased for both substrates.