The dry wear behavior of Al90Mn8Ce2 alloy hot pressed has been studied. It shows that Al90Mn8Ce2 alloy possessed excellent wear resistance. The wear resistance of the alloy pressed at 773 K is three times as high as that of the A355 aluminum alloy. The fine high hardness intermetallic compound and alumina particles contributed to the wear resistance of the alloy.

The effect of melting temperature on the Hall-Petch relationship has been studied. As grain size decreases, the melting temperature of the nano-structured crystals also decreases, therefore the Hall–Petch relationship has its limitation and is no longer sufficient when the grain size decreases to about the 15-30 nm range. When the yield strength or hardness is taken as a function of the reciprocal of the square root of the grain size, it has a numerical maximum whose location depends on the size of the bulk melting enthalpy of the crystals. Experimental results agree well with the modification induced by the size-dependence. In addition, the appropriate size range for the classic Hall-Petch relationship is discussed in terms of the modification of the relationship.

The thermodynamic amount of the pressure-induced solid transition between the wurtzite phase and the rocksalt phase and the melting thermodynamic amounts of the metastable rock-salt phase for CdSe nanocrystals are considered based on known thermodynamic data of the wurtzite phase. Moreover, the static hysteresis width of the above solid transition is also determined. The predictions are found to be reasonable and are in agreement with the present theoretical and experimental results.

The formation tendency of monoatomic chains (MCs) of materials under tensile stress is considered in terms of a ratio between Peierls stress of a bulk crystal having dislocations and the theoretical break shear stress of a monoatomic chain. It is found that the metallic elements having the largest Poisson's ratio (v) and face centered cubic (fcc) crystalline structure hold the largest MC forming ability since they have the smallest elastic energy storage within the crystals and can thus endure the largest plastic deformation. According to the size, sequence of v of metallic fcc elements, the MC formation ability of these elements is predicted, which is in agreement with the available experimental and theoretical results.

The cast pipe joint of the Fe-15Mn-5Si-8Cr-5Ni-0.25C alloy was manufactured (the numbers in the composition denote the weight percentage of the elements while the weight percentage of Fe is the balance). The corresponding microstructure and shape memory effect are compared with those of a forged alloy. The results show that the cast joint has a good shape memory effect and may be industrially applied while the cast joint keeps jointing under a tensile force of 20 kN and a sealing pressure of 5 MPa. Moreover, it is found that the addition of nitrogen in the alloy doesn’t evidently improve the shape memory effect of the alloy.