Cu-14Al-X alloys was made into powder and then the powder was coated onto the surface of AISI 1045 steel respectively via plasma spraying and laser cladding technologies. Microstructure and phases of the coating were investigated by EPMA, XRD, SEM et al. Friction and wear properties of the two coatings were tested by RFT- friction and wear testing machine. The results indicates that the two coatings all consists of β′, α, K and γ2 phases and the structure of laser cladding is more evenly distributed. Under the condition of boundary lubrication, abrasion mechanism of laser coating remains abrasive grain abrasion. There is also adhesion abrasion under the condition of high load. While abrasion mechanism of plasma coating is slight abrasive grain abrasion and adhesion abrasion under low load. With the load increasing, adhesion abrasion intensifies. In a word, microstructure of laser coating is more even and compact.

Taking ZL101A alloy as the research object, the ZL101A alloy test bar was solution treated at 535°C and kept for 5 hours, and then quenched at 25°C, 50°C, 70°C, 90°C water temperature conditions. And then aging the quenched alloy sample at 150°C and heat preservation for 3.5h. After tensile test, Brinell hardness test, using metallographic microscope, scanning electron microscope to observe the metallographic structure, fracture morphology and other methods of analysis, and summarized the changes in the structure and properties of ZL101A alloy under different quenching water temperature conditions. The results show that the elongation, reduction of area, and tensile strength of ZL101A alloy quenched at 70°C are the highest, and the Brinell hardness is the highest when the quenching water temperature is 25°C. Comprehensive practical application, the comprehensive mechanical properties of ZL101A alloy quenched at 70°C are the best.

As product structure becomes more and more complex, the fault mode presents a diversified trend, and it is more difficult to determine the causes of system failure for a complex product. The main objective of this study is to provide an effective failure analysis method based on the combination of fault trees analysis (FTA) and generalized grey relation analysis (GGRA) for complex product. In this method, the product system failure is defined and the fault tree is constructed by FTA methodology firstly; and then GGRA is employed to identify the correlations between each fault mode and the system failure; finally, the main causes of system failure are identified and the corresponding measures can be made. A case study of a WD615 Steyr engine is conducted throughout the text to verify the validity of this method. The present study would help facilitate the failure and reliability analysis for complex product and benefit designers for the product improvement.

The effect of Ce on vitriol corrosion resistance of aluminum bronze alloy coating was studied by static immersing corrosion test, electrochemistry test, XRD, SEM, EPMA, XPS et al. The results show that Ce can improve the corrosion resistance of Cu-14%Al-X coastings. Selective corrosion happened in 5%H2SO4 solution and Al and Fe were prior to be etched. This alloy coatings possesses good corrosion resistance.