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The influence of temperature on the dry sliding wear behavior of as-cast SiCp/A356 composite under 150r/min, 6N and 30 min has been illustrated in this paper. The results reveal that the wear rate is very sensitive to the change of temperature and it exhibits lower wear rate at the range from 100°C to 200°C. However, the wear rate increases linearly due to adhesive wear operating a long duration at 250°C. The friction stability decreases sharply with the temperature raising. Formation of continuous grooves and some damaged regions are presented on the worn surfaces of the samples at lower and intermediate temperature. Parallel lips (wave like material flow) along the sliding direction are observed at higher temperature of the sample. The wear mechanisms involve an initial oxidative wear regime and spalling wear regime for a long duration and followed by an adhesive wear regime as the temperature raising.

Thick alumina coatings were performed on A356-20vol.% SiCp composites by micro-arc oxidation (MAO) process with different processing time. The dry sliding wear tests were performed on A356-20vol.% SiCp composites with and without surface coating. The samples were tested by pin-on-disc wear test equipment with different applied load and sliding velocity. It is revealed that MAO coating improves resistance to wear of A356-20vol.% SiCp composites in the severe wear conditions. On the basis of the observations and analysis of the worn surface, worn subsurface, wear debris and variation of friction coefficient, the role of MAO coating layer is examined.

Deformation behavior of temperature gradient anneal(TGA) treated Ti-50.0Ni(at%) alloys were investigated by means of thermal cycling tests under constant load and tensile tests. TGA treated Ti-Ni alloy wires showed a sequential deformation behavior along the length of the specimen since the stress required for the B2-B19’ transformation increased with decreasing annealing temperature. Considerably large residual elongation(about 0.4 %) occurred in the TGA treated Ti-Ni alloy under the applied stress of 80 MPa, which is ascribed to the fact that yield stress of the sample annealed at 823 K is lower than the stress required for the B2-B19’ transformation of the sample annealed at 658 K.