Phase behaviors of tridecane−tetradecane (n-C 13 H 28 −C 14 H 30 , C 13 −C 14 ) system in bulk, and confined in SBA-15 and controlled porous glass (CPG) are investigated using differential scanning calorimetry and temperaturedependent X-ray diffraction. Bulk C 13 −C 14 mixtures exhibit a complicated behavior featuring a special rotator phase R I . Adsorbed in SBA-15 with pore diameters (d) of 3.8 and 7.8 nm, the binary mixtures display a melting boundary of a straight line and a curve, respectively. Within SBA-15 (17.2 nm) and CPG (8.1, 31.8, 46.4, and 300 nm), the mixtures show a similar phase behavior to the bulk, especially in the larger pore CPG than 30 nm. Under confinement, the phase behavior of C 13 − C 14 mixtures varies with the pore size as well as the temperature and composition. XRD analysis reveals that the solid alkane molecules take effectively the 2D closed-packed arrangements inside pores of diameters less than 20 nm. In the large pore CPG (d > 30 nm), the alkane molecules regain lamellar ordering in solid states. Pore geometries of SBA-15 and CPG, one-dimensional channels vs three-dimensional connected pores, may also result in much different influence on the phase behavior of the confined mixtures.

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The effect of the different electromagnetic stirring frequency after low temperature pouring on microstructures and mechanical properties of Al-7Si-0.42 Mg-0.1Cu alloys was studied. It was found that the primary α-Al becomes smaller and tended to be spherical morphology, and the particles were uniformly distributed after electromagnetic stirring. The tensile strength of alloys improved gradually from 193.02 MPa to 212.54 MPa, and the elongation increased from 3.73% to 6.67% when the stirring frequency was 10 Hz. From the fracture morphology, the fracture for alloy stirred at frequency of 10 Hz showed more dimples than that without stirring. When the stirring frequency increased to 15 Hz, the microstructures of primary α-Al appeared to be dendritic structures, and the grains became coarse. As a result, the 10 Hz was the best electromagnetic stirring frequency.

The commercial pure titanium plate was shot vertically by the projectile with a diameter of 7.62mm at impact velocities ranging from 782m/s to 825m/s. The microstructure around the crater of commercial pure titanium plate was analyzed by optical microscopy (OM) and electron backscatter diffraction (EBSD) methods. It was found that different microstructures were observed along the depth of cater. In upper region of the crater, grains were deformed and fragmented. Adiabatic shear bands (ASBs) were observed in the middle of the crater, and some ASBs were bifurcated. At the bottom of the crater, the grains were less deformed, and the deformation twins were formed. The microstructures in the center of adiabatic shear band were mainly consisted of the dynamic recrystallization grains and sub-grains. The microstructure in the transition region was elongated grains along the shear stress distribution.

In this paper, an Al-Zn-Mg-Cu alloy with a small amount of Er and Zr added was used as the research object. The homogenization annealing was carried out, and the 7N01 aluminum alloy was used at 300 °C, 350 °C, 400 °C, 450 °C and 0.1 s-1, 1 s-1, 10 s-1 deformation conditions by Gleeble-3500 thermal simulator. Optical Microscopy (OM), Scanning Electron Microscopy (SEM), Electron Backscatter Diffraction (EBSD) and Transmission Electron Microscopy (TEM) were used for microstructure analysis. The results show that the stress-strain curve of with Er 7N01 aluminum alloy can be divided into micro-strain stage, uniform deformation stage and steady-state flow stage during the thermal compression process. The flow stress of 7N01 aluminum alloy achieved peaks at the initial stage of strain, and then increased with the increase of strain rate and the decrease of deformation temperature. With the increase of deformation temperature and the decrease of deformation rate, the recrystallization process was significantly increased.