抄録
A new method called“STAC-method”to measure adhesion shear stress of plasma sprayed coating was suggested by Dr.Yamazaki.In reference to this study,the author investigated whether this method can adapt to cold sprayed coating.Test pieces were fabricated by spraying copper powder on aluminum substrates and adhesion shear stress of them was measured by compressive loading so that gage length(Lg)was optimized.In addition the influence of gas temperature and coating thickness(tc)on the shear stress was investigated.As a result,the Lg was required to be more than 3 mm to suppress the dispersion of the shear strength,although the influence of tc was not significant.In investigation of gas temperature,the shear strength at 200,400,600 and 800℃ in the spray temperature were about 57,72,114 and 120 N/mm2 respectively.The test pieces at 200 and 400℃ exhibited brittle fracture and broke in the interface between the coating and substrates.On the other hand,those at 600 and 800℃ exhibited ductile fracture and broke in the aluminum substrates.These results suggest that STAC-method is useful as an evaluation for cold sprayed coating as well as plasma sprayed coating.
