Influence of magnetron sputtering process parameters on wear properties of steel/Cr3Si or Cr/MoSx

The film system steel/Cr3Si or Cr/MoSx was produced by r.f. and d.c. magnetron sputtering with variation of the following process parameters: working pressure P-Ar; sputter power P; and target-substrate distance TSA, in both intermittent and stationary modes. The layer system had a thicknesses <1 mu m; the interlayers were thinner than 100 nm. The chemical characterisation was performed using EDX (energy dispersive X-ray analysis); a structural characterisation was accomplished by X-ray diffraction. The chemical composition was changed by decreasing the TSA, increasing P-Ar or P, and by changing the mode (intermittent or stationary). An increase in P-Ar to values greater than 1.3 Pa at a TSA of 40 or 80 mm was found to lead to an increased oxygen content. The layers were microcrystalline and showed no texture for any parameter set. X-Ray diffraction patterns show mainly the (002) reflection with different degrees of ordering. The wear properties were investigated with the pin-on-disk test. The MoSx layers with (002) reflections without additional (100) or (110) reflections showed only small abrasion. The formation of this modified MoS, layer is the connecting link between process parameters and wear properties.