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The Cu-Cr and Cu-Cr-Ti alloy plates were prepared by vacuum melting and plastic deformation. The effect of slight Ti element on microstructure and mechanical properties of Cu-Cr alloy was discussed. The result shows that Cr particles with spherical shape precipitated from Cu matrix after aging. Plenty Ti atoms dissolved in the vicinity of Cr particles and there were still parts of solid solution Ti atoms in other regions. Improvements in peak hardness and softening resistance were achieved with the addition of Ti element in Cu-Cr alloy. The addition of 0.1 wt.% Ti element makes Cu-Cr alloy possess tensile strength of 565 MPa and hardness of 185.9 HV after aging at 450 °C for 120 min, which can be attributed to multiple strengthening mechanisms, i.e. work hardening, solid solution strengthening and precipitation strengthening.

If there are local defects in the solar cell module, the output efficiency of the module will decrease. This article introduces the detection of local defect of solar cell module based on the infrared image technology. It finally establishes an image library which contains some infrared images of seven kinds of defects and a basic standard which can judge the quality of the module. The reasons of some defects are listed in the article. The unqualified rate will greatly decrease for the technique. The research is helpful to eliminate the module that contains recessive defects. The life of the modules also will be extended.

Cu-Ag-Zr alloy is a newly developed copper alloy material with an excellent combination of high mechanical strength and high electrical conductivity. Magnetic field was used in the solidification of Cu-Ag-Zr alloy. The results showed that with the application of magnetic field, formerly coarse columnar grain turned into homogeneous equiaxed grain. After aging, the precipitate of Zr had an increment and became more refined due to the reduction of segregation. The tensile strength and microhardness of Cu-0.1Ag-0.3Zr alloy under magnetic field of 15 mT increased by 17% and 10%, respectively. The electrical conductivity, with a slight decrease, was still as high as 92.4 %IACS.

A bulk casting ingot (Ø70 × 150mm) of CoCrFeNiTi0.5 high entropy alloy was prepared by vacuum medium frequency induction melting. The samples from the ingot were aged for 12h in the temperature range of 900-1100°C and then quenched in water to investigate the effect of aging temperature on the microstructure and hardness of CoCrFeNiTi0.5 alloy. The crystalline structure of as-cast CoCrFeNiTi0.5 alloy consisted of the principal face-centered cubic (FCC) dendrite phase plus (Ni, Ti)-rich R phase, (Fe, Cr)-rich σ phase, (Co, Ti)-rich Laves phase within the inter-dendrite area. The dendrite contained approximately equivalent amount of Co, Cr, Fe, Ni and a smaller amount of Ti element. After aging treatment in the temperature range of 900-1000°C, the (Co, Ti)-rich phase disappeared while the amount of (Ni, Ti)-rich phase and (Fe, Cr)-rich phase increased. But the volume fraction of FCC dendrite phase increased and the intermetallic phases decreased after aging at 1100°C. The micro-hardness and the macro-hardness of the as-cast CoCrFeNiTi0.5 alloy were HV616.8 and HRC52, respectively. After heat treatment at 1000°C, the micro-hardness and macro-hardness decreased from HV616.8 to HV386.8 and from HRC52 to HRC42.7, respectively.