Cavitation Erosion Resistance Influence of Material Properties

Abstract

The cavitation erosion is the phenomena that causes degradation of fluid flow machinery components due to repetitive implosion of cavitation bubbles adjacent to the solid surface. Cavitation erosion is a complex phenomenon, which includes not only hydrodynamic factors of liquid, but also properties of erodible material e.g. microstructure, hardness or Young modulus. In order to reduce the negative impact of erosion on machine components, there are many methods to increase cavitation erosion resistance. The paper discusses the correlations between structural and mechanical properties and the resistance to cavitation erosion (CER) of pure materials, their alloys and coatings. Methods to increase CER have also been described - using heat / thermo-chemical treatment and application of coatings by various methods.

Microstructural and Cavitation Erosion Behavior of the CuAlNi Shape Memory Alloy

“…Moreover, it was observed that the CuAlNi alloy in as-cast condition is softer (344 HV10) than after quenching (480 HV10), which suggested that resistance to cavitation erosion is better after quenching than that in the as-casted state. This is in contrast to the behaviour of other materials, which show that higher hardness of the materials gives better resistance to cavitation erosion [20]. This area definitely requires further investigation.…”

“…Figure 4 shows the micrographs of microstructure in both as-cast and quenched states, before and after 420 min of exposure to cavitation testing obtained by an optical Cavitation erosion is a phenomenon that includes not only properties of liquid, but also the properties of material, for example, hardness, microstructure, grain size of material, and so on. It is known [20] that the material with a homogeneous and fine-grained structure has the highest cavitation erosion resistance, good mechanical properties, and high corrosion resistance. In the literature, there is no information about cavitation resistance testing of CuAlNi shape memory alloys.…”

“…Cavitation erosion test was performed using the ultrasonic vibration method (with stationary sample), according to ASTM G32 standard [32]. The experimental set-up is described in detail in previous papers [18,20,30,31]. The gap between the surface of the samples and the transformer probe was 0.5 mm.…”

“…Cavitation phenomena were studied in many papers and well described for the materials regarding many applications [12][13][14]. Cavitation damage test is usually used for metallic materials [15][16][17][18] and coatings [17][18][19], with great interest on material properties' influence [20] such as cobalt alloys [21], WC-12Co coatings [22], and Monel K-500 alloy [19]. Among shape memory alloys, the cavitation erosion was tested primarily for nitinol alloy [23][24][25] and Fe-based shape memory alloy [26], while for CuAlNi alloy, references were not observed.…”

Cavitation Erosion and Sliding Wear of MCrAlY and NiCrMo Coatings Deposited by HVOF Thermal Spraying

“…microstructure, mechanical properties, material surface morphology, etc. [8,9]. Moreover, according to the literature [10][11][12], the abrasive wear and particularly sliding wear are dominant processes of materials degradation.…”