A study on the behaviour of corrosion-erosion at the Bearing metals by cavitation(1) (for the influence of pH)

Recently, due to increased occurrence of cavitation-erosion at slide bearing metals with the tendency of high speed and large output at internal combustion engine, there is a need to study the role of corrosive environments on cavitation-erosion. Therefore, this paper were investigate on the behaviour of cavitation-erosion under the change of pH environments at slide bearing metals with using piezoelectric vibratory apparatus. The main results obtained were as follows: 1. The weight loss and its rate showed to be increased according to the order of pH 2 > pH 12 > pH 7 > pH 4 environments, and also retarded extremely at pH 4 environment 2. The resistance of material on cavitation-erosion was excellent at pH 4 environment, and also was improved considerably its resistance with increasing of the space between specimen and horn tip. 3. It was showed that the incubation periods shortened with the tendency of pH 2 > pH 12 > pH 4 > pH 7 environment, and enlarged greatly at pH 7 environment. 4. The pitted holes of damaged surface under pH 4 environment showed dense aspects by comparison with pH 7 environment