The effect of post annealing temperature on the microstructure, martensitic transformation behavior, mechanical properties and shape memory effect of the cold rolled Ti-13V-3Al-0.5Cu (%, atomic fraction) alloy was systematically studied by means of XRD, TEM, DSC and tensile test at room temperature. The results showed that the phase composition of the alloy at room temperature was mainly α" phase, together with a small amount of remained β phase, α phase and Ti₂Cu second phase. With the increasing annealing temperature, the shape memory property increased firstly and then decreased. When the annealing temperature is 750℃, the alloy showed a good shape memory effect and the recoverable strain up to 5.3% when the pre-strain was 6%. Furthermore, the morphology of martensite transformed from a V-shape like self-coordinated-structure to a structure of single preferential orientation when the alloy was subjected to a proper cold rolling and annealing treatment. Lower reorientation critical stress and better interface mobility were the main causes for the improvement of shape memory effect.

Tensile properties of a single-strand conductor of 6101 Al-alloy were investigated in the temperature range from -70℃ to 70℃. It is found that the 6101 Al-alloy wire has high strength and good deformation uniformity at the low temperature (-70℃). However, the yield strength and the ultimate tensile strength of the alloy exhibited a decreasing trend with the increasing testing temperature. The ultimate tensile strength and the yield strength of the alloy at 70℃ decreased by 10.9% and 9.3%, respectively, comparing with those of the counterparts tested at -70℃. From the analysis on the correlation of the work hardening rate and the yield strength with the temperature, it is found that the strain hardening rate of the alloy decreased with the increasing flow stress and the raising temperatures. In addition, the lattice friction stress has a strong correlation with temperature, which is the main factor affecting the yield strength of the alloy. Based on the comparison of the fitting calculated increment of the yield strength of the alloy to the corresponding experimental results, a model about the relation between the yield strength of the alloy and the service temperature was obtained, by which the appropriate yield strength of the alloy at different service temperatures can be predicted.

Cast ingot of Al-5.5Mg-0.25Sc-0.04Ti alloy was prepared by chill casting, and of which the hardness change with time at different annealing temperatures was assessed by hard- meter. While the morphology and formation process of the precipitates Al₃(Sc_x,Ti_1-x) of the alloy were investigated by means of metallographic microscopy (OM) and transmission electron microscopy (TEM). The results show that Sc and Ti atoms mainly exist as solid-solute in the α-Al matrix when the alloy was made by chill casting, while in such case, precipitates Al₃(Sc_x,Ti_1-x) could hardly be observed by electron microscopy. Annealing at lower temperatures (below 250℃) the hardness of as-cast alloy increases slowly, and the hardness peak appears only after a long annealing time. Annealing at higher temperatures (above 350℃) the hardness increases very quickly, and the hardness peak of the alloy appears quickly, but when the hardness peak appears the hardness will decrease greatly as the annealing continues. Among others, the alloy presents the highest thermal stabilitywhen annealing at 300℃. The changes in hardness are closely related to the secondary precipitates of Al₃(Sc_x,Ti_1-x). If the annealing temperature is lower, the precipitates of Al₃(Sc_x,Ti_1-x) is incomplete and their size is smaller, so the pinning effect on grain boundary, subgrain boundary and dislocation is weaker. But when the annealing temperature is higher, the coarsening of precipitates of Al₃(Sc_x,Ti_1-x) will occur, it results in poor alloy properties.

Multilayered films of Al/AlN/GaN were deposited on a Si wafer by metal-organic chemical vapor deposition (MOCVD). The microstructure and crystallinity were characterized by means of optical microscopy (OM), atomic force microscopy (AFM) and X-ray diffractometer (XRD), especially in terms of the mechanisms of nucleation and growth of the produced AlN and GaN films with the variations of trimethylaluminum (TMAl) flow during Al pre-deposition process. It was observed that the pre-deposited Al layer helps the nucleation and growth of AlN film and thereafter improves the quality of GaN film. When a thin Al layer was deposited at low TMAl flow, the quality of the AlN film depends on the competition between the nucleation and growth of the high crystallinity AlN thin film with the deposition of the formed clasters of low crystallinity AlN in the gas phase on the surface of silicon wafer. The quality of the AlN film increases with increasing TMAl flow, inducing the formation of GaN film with better quality. When the Al layer is too thick at high TMAl flow, the quality of the AlN film depends on the competition between the nucleation and growth of the high crystallinity AlN thin film with the meltback-etching of Al-Si on the wafer surface. The quality of the AlN film decreases with increasing TMAl flow, inducing the formation of GaN film with worse quality.

The samples of Fe_74.1Cu₁Nb₃Si₁₅B_6.9 (atomic fraction, %) nanocrystalline alloy were subjected to continuous tension annealing treatment, while the effect of the continuous tension annealing induced-anisotropy on their structure and magnetic properties was investigated. The results show that the induced anisotropy constant (K_u) and annealing tension (σ) fit linear relationship in the presence of tensile stress. The effective permeability (μ_e) at test points f=5 kHz and H=3 A/m first increased and then decreased with the increase of annealing tension. The increase of annealing tension decelerate the process of effective permeability (μ_e) attenuation, which can remain constant over a wide range of magnetic field and frequency. Compared with other samples, the effective permeability (μ_e) of the alloy is nearly 800 in the testing range of 0~800 A/m (magnetic field) and 1 k~1 MHz (frequency) when tensile stress is 67 MPa. That show the tension annealed alloy has an excellent constant permeable property. Otherwise, with the increase of annealing tension the unit mass loss of the alloy decreases. When tensile stress is 67 MPa the unit mass loss of the alloy approximates 68 W/kg (testing condition: B_m=300 mT, f =100 kHz), which reduces nearly 67% compared with the absence of annealing tension. Besides, the 180° stripe magnetic domain observed by magneto-optical Kerr microscopy is perpendicular to the tensile stress on the alloy. The increase of tensile stress leads to decrease of the width of domain structures in the alloy and tends to comparable. When tensile stress is 67 MPa the width of domain structures is about 85 μm.

Carbon dots (CDs) were synthesized from 4-aminosalicylic acid (ASA) by a hydrothermal carbonization technique and then incorporated into the membrane casting solution. Then polysulfone/carbon dots (PSF/CDs) nanocomposite membranes were prepared by non-solvent induced phase separation. The results of transmission electron microscopy (TEM) and Fourier transform infrared spectroscopy (FTIR) show that CDs with a lot of hydrophilic groups had been successfully synthesized. Water contact angle analysis (WCA), scanning probe microscope (SPM) and scanning electron microscope (SEM) were used to characterize all membranes. It could be found that nanocomposite membranes have better hydrophilicity and water flux than the original membrane. Therefore, the anti-fouling performance of the modified membranes had also been improved. Flux recovery rate (FRR) of the fabricated PSF/CDs membrane is higher than 90%, total fouling ratio (Rt) is less than 60%, and the reversible fouling played a dominant role during the fouling process. When the CDs content (mass fraction) is 2%, the overall effect of the membrane is the best with comprehensive performances such as separation efficiency, separation effect, and antifouling ability etc. The water flux of the nanocomposite membranes with stronger anti-fouling ability is even 3 times that of the plain PSF membrane.

The pure ZnO and Ag-modified ZnO composite photocatalysts were prepared by sol-gel method and subsequently heat treated at 400℃, 450℃ and 500℃ respectively for 2 h. The samples were characterized by XRD, SEM, TEM, XPS, PL and BET, respectively. The results show that both pure ZnO and Ag-ZnO are hexagonal wurtzite crystal structures. Ag particles deposit on the surface of ZnO, forming Ag-ZnO heterostructure. The photocatalytic activity of samples was assessed through the degradation of Rhodamine B. The results show that the heat treatment temperature has a great influence on the photocatalytic performance of pure ZnO, while the pure ZnO annealed at 450℃ exhibits the best photocatalytic activity. However, the annealing temperature has negligible impact on the photocatalytic activity of Ag-ZnO and all of the Ag-ZnO samples show better photocatalytic activity than that of the pure ZnO. The enhancement in photocatalytic activity of Ag-ZnO can be attributed to the effect of suppressing the recombination of photogenerated pairs and the increase of surface hydroxyl content. The degradation rate of RhB for the Ag-ZnO annealed at 500℃ is 98% after 60 min and the reaction rate constant is 0.063 min^-1.

Combining the advantages of organic coating with self-healing ability and alloy plating, a composite coating Cap(T+Y)/ Ni-Co was prepared on the Q235 substrate in order to improve the anti-corrosion ability and extend the service time of the coated steel. At first the Ni-Co alloy plating was electro-deposited on Q235 carbon steel, and subsequently, the two-component microcapsules containing organic coating was applied on the Ni-Co/Q235 to acquire a composite coating. Results of SEM observation and thermogravimetry analysis show that the diameter of microcapsules is about 3 μm with a coverage up to 49%. Besides, results of neutral salt spray tests and localized electrochemical tests show that the composite coating presents a well integrality after undergoing 380 h salt spray test. The anticorrosive composite coating has satisfactory self-healing activity and long-term protectiveness on the Q235 metal matrixes.

A novel MgAl₂O₄:Mg phosphor was prepared by ultrasonic assisted polyacrylamide gel method. When Mg metal particles were introduced into the MgAl₂O₄ system, the formation of MgAl₂O₄ phase was inhibited. When the xerogel powder MgAl₂O₄:Mg was sintered at 900℃ or above, the incorporated Mg-particles are oxidized to be MgO. The introduction of Mg-particles greatly changed the morphology of MgAl₂O₄:Mg phosphors, namely from tiny nanoparticles to instant noodles-like. The results show that the sintering temperature has great influence on the color, light absorption capacity, energy band E_g and photoluminescence properties of MgAl₂O₄:Mg phosphors. The color of MgAl₂O₄:Mg phosphors changes from dark brown for sintering at 600℃ to bright white at 800℃ and then to light white at 1000℃. With the increase of sintering temperature the E_g value of MgAl₂O₄:Mg phosphors increased first and then decreased slightly. The photoluminescence spectra show that three new photoluminescence emission peaks located at 650, 656 and 680 nm are observed when the excitation wavelength is 325 nm. The photoluminescence intensity decreased with the increasing of sintering temperature. The fluorescence emission peaks at 395 and 425 nm of host lattice MgAl₂O₄ were quenched. The surface plasmon resonance (SPR) of Mg metal particles led to the fluorescence quenching of MgAl₂O₄ host lattice, and the defect energy level can produce a new fluorescence emission band at 635~690 nm of MgAl₂O₄:Mg phosphors.

In order to pursue energy-saving, economic, lightweight as the goal, the so called transformation-induced plasticity (TRIP) effect was utilized to solve the contradiction for improving strength and plasticity simultaneously for steel products. Hence, following the above mentioned technology, a series of 1 GPa grade TRIP-assisted bainitic ferrite (BF) steel products were produced, while the microstructure, strength and ductility were investigated for steels subjected to various type of microstructural controlling. The results show that the steel with the microstructure composed of c.a. (75~85)% of bainitic ferrite and ≥15% of retained austenite may be acquired advantageously. For that purpose the reasonable chemical composition design and the initial hot-rolled steel was controlled to be with the microstructure composed of (20~30)% of ferrite and (70~80)% of needle-like bainite as the prerequisite, thereby, the comprehensive mechanical properties could be ensured for 1 GPa grade TRIP-assisted BF steel. The reasonable proportion of a dual phase structure and the morphology features have great influence on the strength and ductility of the TRIP-assisted BF steel. While the lamellar retained austenite with the width within the range of 80~130 nm were distributed uniformly in the matrix structure of 82% bainitic ferrite, through the compatible deformation between dual phases the excellent comprehensive mechanical properties were achieved, namely the elongation rate was 20.3%, and the product of tensile strength and ductility reached to 22.0 GPa· %. The strength reached to 1099 MPa when the lath width of bainitic ferrite was within the range of 0.15~0.45 μm and the width of lamellar-like retained austenites was within the range of 50~90nm. When the steel was subjected to a sudden collision the residual austenites(about 6%)may be induced to response a secondary TRIP effect so that to increase its energy absorption ability, hence improving the anti-collision ability of the relevant automobile parts.