The Study of the Grit-blasting Parameters and Their Effects on the Adhesive Strength of the Plasma Sprayed Coatings

作     者：M Heydarzadeh Sohi M Frooghieh Sh Khameneh Asl 

作者机构：Dept. of Metallurgy and Materials Engineering Faculty of EngineeringUniversity of TehranDept. of Metallurgy and Materials Engineering Faculty of EngineeringUniversity of TehranDept. of Metallurgy and Materials Engineering Faculty of Engineering University of Tehran IranIranIran 

出 版 物：《厦门大学学报（自然科学版）》 (Journal of Xiamen University：Natural Science)

年 卷 期：2002年第41卷第S1期

页      面：108-109页

核心收录：

学科分类：080503[工学-材料加工工程] 08[工学] 0805[工学-材料科学与工程（可授工学、理学学位）] 

主　　题：The Study of the Grit blasting Parameters and Their Effects on the Adhesive Strength of the Plasma Sprayed Coatings 

摘      要：Surface Preparation is very important in adhesive b on ding of spray coatings to the surface of a work piece. The common practice is gr it-blasting of the surface before subjecting it to the spray coating process. In this study, grit-blasting of an AISI 4130 steel (of different heat treatmen ts) with Al 2O 3 particles was studied. Various grit-blasting parameters such as blasting particle size, the distance between blasting nozzle and the work pi ece (25, 30 and 40 cm.), blasting pressure (3,4,5,6 and 7 bars), blasting time ( 3, 6 and 10 seconds), and the blasting angle (45° and 90°) were examined in or der to find the optimum roughness. The mean roughness (Ra) of the grit-blasted surfaces were measured and the vari ations of the roughness with respect to the above mentioned variables were studi ed. The results show that by increasing blasting time, surface roughness increas es up to a maximum and then slightly decreases it with further duration of t he process. On the other hand a lengthy blasting causes some undesirable results such as an increase in residual particles between surface irregularities. There fore an optimum blasting time is of great importance. Increasing the blasting pr essure also provides a rougher surface, but in grit blasting of harder specimens the surface roughness decreases when the pressure reaches a certain limit. About the blasting angle, it was noticed that an angle of 45° results in less r esidual particles between the surface irregularities, in comparison to the angle of 90°. After grit-blasting, the specimens were plasma spray coated with 80% ZrO 2-20 % Y 2O 3 powder. The adhesive strength of the coating to the substrate was the n measured according to the DIN 50160 standard. The results show that for a certain base metal, the adhesive strength is directl y related to the surface roughness of the base material. Residual particles afte r grit-blasting the surface of the specimens can also have a strong deteriorati ng effect on adhesive