The influence of annealing temperature on mechanical properties and friction coefficient of coating layer in galvannealed sheet steel

합금화 용융아연도금강판에서 어닐링 온도가 도금층 기계적 특성 및 마찰계수에 미치는 영향

In the modern days, a galvannealed sheet steel (GA) instead of a cold rolled steel sheet has been widely used as an alternative to extend the life of automotive body. Accordingly, the mechanical properties of GA for automobiles were taken into account and studied by comparing with the temperature variation on annealing in this study. To clarify the effect of surface features in the mechanical and frictional properties of GA, the several tests such as nanoindentation, victors hardness and nano scratch test were executed. The developed neural networks apply also to obtain reliable mechanical properties of the thin films. Load-displacement curve was computed by the analysis procedure and compared with experimental results. The frictional characteristics of coating layers in GA were verified though nano scratch test in this study. The friction coefficient of coating layers on the surface was obtained from the nano scratch. The variation of friction coefficient versus velocity and pressure was taken into consideration in this paper.