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The influence of grain size of Ni3Al alloy on cavitation wear of Ni3Al intermetallic after cold rolling and recrystallization during incubation period

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Unbeneficial phenomenon of cavitation is very common and can be observed in many fields of life. In particular, it appears in hydraulic machines and systems, and as well as in automotive and shipbuilding industries. Cavitation wear has been a subject of many publications and scientific works since the end of 19th century. However, recent state of knowledge of this phenomenon is still insufficient. Osborn Reynolds was the first who described this phenomenon in 1894. The meaning of term cavitation was taken from latin word cavitas which means cavern, void. Cavitation was firstly recognized as the reason of screw propellers and turbine rotors destruction at the turn of the 19th century. The first accurate definition of cavitation has been created in 20th century, and then material research as an attempt to full explanation of this effect has been introduced. Cavitation has been also noted in sliding vane-pumps, gear wheels, pipelines and fittings. Cavitational erosion is an effect of mechanical devastation of material, due to implossions of cavitational bubbles in the nearby or directly on material’s surface, what results in weight loss. Microbubbles serve as a cavitation embryos, which can be periodically recreated, due to release of gases from liquid. The effect of periodically repeated compression and implosion of gas bubbles is accompanied by rapidly changing impulses of pressure with value of even 1 GPa. Especially dangerous conditions can be achieved if microbubbles form cavitational clouds, which can lead to simultaneous implossion of large amount of bubbles and creation of very high pressure impulse. Formation of accumulative beam of liquid which moves with speed of 100 m/s, is also possible in critical conditions [1÷5]. Surface zone strengthening, microcracks, material loss and microstructure changes are appearing in the material as a result of continous impact of pressure pulses [6÷8]. Special attention has been f[...]

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