The control of experimental conditions is imperative in the study of cavitation characteristics in polymer solutions. First, qualification of steady-state physical properties should be acquired for a given polymer solution. Second, the approaches to keeping the physical properties stable should be incorporated into the process of cavitation tests. The present investigations contain two aspects involving the steady-state conditions of certain polymer solutions for long ageing times and for experimental processes, as well as cavitation erosion performance, in polymer additives. As far as polyacrylamide solution is concerned, the findings demonstrate that the critical ageing time of the steady-state viscosity occurs at various concentrations and temperatures; viscosity is almost constant throughout the course of the vibratory tests, with a solution circulatory system attached. Based on viscosity stability, cavitation erosion of AISI1045 steel performs with good regularity and decreases with the increase of concentration as well as the decrease of temperature.