Papers by Keyword: CFUMS

Abstract: CrSiN coatings of different silicon content were deposited on 1Cr18Ni9Ti austenitic stainless by d.c. reactive magnetron sputtering in a closed field unbalanced system. Comparative studies on microstructure and mechanical properties between CrN and CrSiN coatings with various Si contents were carried out. The structure of the CrSiN coatings was found to change from crystalline to amorphous structure as the Si contents increased. Amorphous phase of Si₃N₄ compound was suggested to exist in the CrSiN coatings. The crystalline grain became smaller in CrSiN coatings. With the increasing Si content, the coating deposition rate slew down, while the hardness of coatings improved obviously and the best hardness was about 4200 HV_0.01 when the Si content was 1.13%.

Abstract: CrN_x coatings were prepared by closed filed unbalanced magnetron sputtering (CFUMS), and the effects of N₂ flux ratio and bias voltage on CrN coatings were investigated. Results showed that the phase in coatings was the coexistence of CrN, Cr₂N and Cr, and CrN(111) always showed an intensive preferred orientation in both cases, but CrN(200) enhanced with the rise of bias voltage. The hardness of coatings decreased with an increasing N₂ flux ratio, while improved with an increasing bias voltage. The grain edges were polished off and the boundaries became blurred when higher bias voltage was applied. All in all, the surface morphologies of CrN coatings became flatter and denser with both increasing N₂ content and bias voltage, respectively.

Abstract: CrN coatings were fabricated by Closed Filed Unbalanced Magnetron Sputtering (CFUMS). The effect of substrate temperature (T_S) on phase components, morphologies and mechanical properties of CrN coatings were studied. The results show that the phase in coatings, which has little to do with T_S, was the coexistence of Cr, Cr₂N and CrN. The grain shape of the columnar crystal CrN coating was the coexistence of pyramidal and plane topography. The hardness and adhension of CrN coating first increased with the rise of temperature, then decreased when the values of both them were constant ones. It has the highest hardness and bonding strength simultaneously at 300°C.

Abstract: CrN coatings were deposited by Closed Filed Unbalanced Magnetron Sputtering (CFUMS). The effect of N₂ flow rate on composition, phase components, morphologies and mechanical properties of CrN coatings were studied. The results show that the deposition rate of CrN coatings declined with the increase of nitrogen flow percentage in a Ar/N₂ mixture atmosphere. When the nitrogen flow percentage reached 50% or more, the Cr and N atomic ratio of CrN coatings is close to 1:1. The phase in coatings was the coexistence of Cr, Cr₂N and CrN, but the crystal preferred orientation changed significantly with the different N₂ flow rates. The columnar crystal CrN coating with low N₂ flow rate was denser. The hardness and adhension of CrN coatings have no direct relationship with N₂ flow rate.