M. Fukumoto et al., IMPROVED RING SHEAR TEST FOR THE EVALUATI ON OF ADHESION STRENGTH OF THERMAL SPRAYED COATING, Nippon Kinzoku Gakkaishi, 59(1), 1995, pp. 84-88
The ring shear test was modified to evaluate the adhesion properties o
f plasma sprayed coatings. To ensure the ring shear test to be reliabl
e, the conditions of some main factors, such as coating thickness, coa
ting width and rod-jig clearance, for the evaluation of the adhesion s
trength were evaluated. The results obtained in this research are summ
arized as follows: 1) In order to develop the accuracy of the loading
exactly along the specimen's axial direction, the loading stress unifo
rmity on the coating and the uniformity of the clearance between rod a
nd jig, the conventional ring shear test was modified in shapes of bot
h the shearing jig and the specimen and the loading manner. Consequent
ly, the reproducible results with less scattering were obtained by usi
ng the modified ring shear test. 2) To ensure this modified ring shear
test as the method to evaluate the adhesion strength of plasma spraye
d coating, the necessary conditions of some main factors were evaluate
d. It was found that coating width, coating thickness and rod-jig clea
rance should be fixed to some moderate values.