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The paper presents the results of the research on the vibration cavitation erosion of the CuSn12-C bronze, subjected to the volumetric heat treatment of quenching to 700 °C, with water cooling, followed by tempering to 250 °C, with slow cooling in the air. The applied heat treatment shows the improvement of the behavior and the resistance to the cavitation erosion, compared to the initial state, of molded semi-finished product. The evaluation of the behavior and the resistance to the cavitation erosion is made by comparing the value of the parameters MDEmax, Rcav and Rz with those of the delivery state, as well as on the comparison of the characteristic curves MDE(t) and MDER(t) with those of the CuNiAl I-RNR bronze (used at propeller casting). The tests were conducted on the vibrating apparatus with piezoceramic crystals from the Cavitation Laboratory of the Polytechnic University of Timisoara.

The bronze CuSn is used sometimes for equipment components working in cavitation conditions, as for example ship propellers, bodies and other parts of valves. To increase the working time, in cavitation conditions, those elements can be subjected to volumetric thermal treatments. The present research is concerned with the increase of the mean durability δ ¯ c a v , of the bronze CuSn12 by applying two volume treatments: quenching both at 700°C and 800°C, with tempering at 500°C. The cavitation erosion behavior was experimentally tested using the standard vibratory device of the Cavitation Laboratory of Timisoara Polytechnic University. Comparing the results we found that the durability, in both cases, is substantial increased, the better solution being the quenching with the lower temperature.