A structural and mechanical analysis on PVD-grown (Ti,Al)N/Mo multilayers

(Ti,Al)N/Mo multilayered hard coatings have been designed to fulfil future applications concerning wear-prevention on tool steels. They have been depo sited by reactive de magnetron sputtering on high-speed steel substrates wi th modulation periods between 6.5 and 8 nm. Experimental X-ray diffraction (XRD), Rutherford backscattering spectrometry (RBS) and computational model ling of those patterns has undergone to survey structural properties such a s modulation periodicity, interfacial roughness and density. Asymmetric XRD measurements confirmed that the textured grains, although being randomly d istributed, possess a slight misorientation of +/-11 degrees due to their m osaic structure. Atomic force microscopy (AFM) analysis revealed a dome-rou nded structure with columnar grain sizes between 90 and 120 nm in diameter, depending on deposition process parameters. The average ultramicrohardness of these multilayers can be as high as 36 GPa with a maximum Young's modul us of 445 GPa, while the adhesion critical load may reach 60 N. (C) 2000 El sevier Science B.V. All rights reserved.