Cavitation erosion of age-hardenable aluminum alloys

Evaluation of cavitation erosion resistance of Al-Si casting alloys: effect of eutectic and intermetallic phases

“…At this regard, some authors report the hardness as an indicator of the erosion resistance. Nevertheless, these models reached limited success in prediction erosion damage, as well as the attempt to correlate cavitation resistance and hardness [14][15]. Damage due to cavitation can occur also on various aluminum automotive components, as such as cylinders and pistons, combustion chambers, etc.…”

“…For this reason, over the years, several studies have been performed in order to investigate the cavitation erosion resistance also of aluminum alloys and to correlate it to microstructural and mechanical properties. Concerning the family of wrought alloys, various alloys belonging to the Al-Cu, Al-Mg, Al-Si-Mg or Al-Zn-Mg families were tested in different conditions [14,17] taking also into account the influence of real erosion environments, as for instance the presence of aggressive fluids or slurries [8,18]. For casting alloys, in general, it was found that Al alloys resistance is strongly affected by several microstructural properties, as such as grain size, number of interfaces between different phases, presence and morphology of secondary phases [14][15][19][20].…”

“…Concerning the family of wrought alloys, various alloys belonging to the Al-Cu, Al-Mg, Al-Si-Mg or Al-Zn-Mg families were tested in different conditions [14,17] taking also into account the influence of real erosion environments, as for instance the presence of aggressive fluids or slurries [8,18]. For casting alloys, in general, it was found that Al alloys resistance is strongly affected by several microstructural properties, as such as grain size, number of interfaces between different phases, presence and morphology of secondary phases [14][15][19][20]. This is not surprising since various studies report the influence of eutectic [21][22] and intermetallic phase [23][24][25], as well as the role of grain size [26][27], on other mechanical properties.…”

“…Furthermore, it is well known that a proper choice of heat treatment parameters can increase several mechanical properties [31][32][33]. For this reason, the influence of heat treatment on cavitation resistance was investigated and various studies demonstrated the beneficial contribution of age hardening on reducing material damage [14,[19][20]. Considering the erosion mechanism, under continuous exposure to cavitation, it is reported in scientific literature that the initial undulations of the exposed surface gradually develop into craters and material is lost by necking of the rims of the craters, flaking and dislodging of secondary phases [1,3,14,19].…”

“…For this reason, the influence of heat treatment on cavitation resistance was investigated and various studies demonstrated the beneficial contribution of age hardening on reducing material damage [14,[19][20]. Considering the erosion mechanism, under continuous exposure to cavitation, it is reported in scientific literature that the initial undulations of the exposed surface gradually develop into craters and material is lost by necking of the rims of the craters, flaking and dislodging of secondary phases [1,3,14,19]. Hence, it appears evident a dependency of cavitationerosion behavior on the alloy microstructure, not simply related to the heat treatment effect.…”