Wet Abrasive Wear Behavior of Cu-Al-Be Shape Memory Alloys

Two kinds of CuAlBe shape memory alloys were prepared by means of vacuum medium frequency induced oven melting and metalmold casting. The antiabrasion behaviors of the alloys sliding against emery (SiC) papers in the presence of dripping water as the lubricant were evaluated on a finishing machine. The worn surface morphologies and compositions of the alloys were examined by means of scanning electron microscopy and energy dispersive spectrometry. It was found that the Cu11.42Al0.35Be0.18B alloy (alloy 1) of lower hardness had better abrasivewearresistance than the harder alloy Cu11.81Al0.59Be (alloy 2). This was attributed to the thermal elastic martensite microstructure of the alloy 1. Namely, alloy 1 experienced stress inducedβphase martensitic transformation and preferential orientation of the varied martensite under waterlubricated sliding against emery (SiC) papers. Therefore, alloy 1 of β1plusβ microstructure was able to resist plastic deformation and crack propagation by way of elastic recovering in the abrasion process, owing to the shape memory effect. This accounted for the better abrasivewearresistance of alloy 1 than alloy 2.