The Effect Of Shot Peening On Damage Caused By Cavitation

Author:  Grossman, N.
Source:  ASTM: Bull. No. 183, TP107, July 1952
Doc ID:  1952006
Year of Publication:  1952
Abstract:  
Cavitation in a liquid may result from rapid relative motion between the metal and the liquid, for if the pressure accompanying this high velocity drops to the vapor pressure of the liquid, the liquid will vaporize and form a vapor cavity. The collapse of this bubble will cause a concentrated liquid impact resulting in erosion and pitting of the metal surfaces. The designer of hydraulic machinery tries to eliminate this hazard by proper design. In many cases, however, the operating conditions are such that higher efficiency or better economy is attained by operating near cavitation conditions, or even with occasional cavitation present. The task of the designer then becomes in addition to proper design the selection of a suitable material that will be less susceptible to cavitation damage. In the present study the effect of shot peening on the rate of cavitation damage was investigated. Two steels and one brass were tested. It was found that the damage, as measured by the rate of weight loss per unit time, was decreased by shot peening. The amount of decrease varied from 7 to 58 per cent for the different materials.