The corrosion behavior of 7A09 alloys exposed to an industrial atmosphere for 36 months was studied by weight loss method, morphology observation, electrochemical method, and loss in mechanical properties. Under the condition of exposure to an industrial atmosphere, the 7A09 alloy suffers obvious pitting corrosion and intergranular corrosion (IGC), and a charge transfer process controls the corrosion reaction. The corrosion rate presents a decreasing tendency with exposure time, which is mainly due to the enhancement of the protective ability of the corrosion product layer. The occurrence of IGC of this alloy is mainly caused by the preferential dissolution of the grain boundary precipitates Mg(ZnAlCu) 2 and the precipitate-free zone along grain boundaries, and which leads to the reduction of the mechanical properties. In addition, the morphology and composition of the corrosion product layer were identified, and the corrosion mechanism was also discussed.

Under the background of dual carbon target, the manufacturing industry in the Guangdong-Hong Kong-Macao Greater Bay Area (GBA) is facing the pressure of green transformation. This paper takes this as the research basis, collects the production panel data of the manufacturing industry in the GBA in the past decade, calculates the green development level of the GBA and finds out the important influencing factors, so as to provide theoretical suggestions for the green production and green development of the manufacturing industry in the GBA.

The environmental adaptability of 2A12-T6 aluminium alloy exposed in marine, cold and plateau atmosphere environments has been investigated by corrosion morphology observation, weight loss test and mechanical properties test. the results showed that compared with cold and plateau atmosphere environment, 2A12-T6 aluminum alloy presented higher corrosion susceptibility in marine atmosphere environment; Cross-section morphologies analysis manifested that 2A12-T6 aluminum alloy suffered pitting attack in marine atmosphere environments, and the corrosion is very slight in the cold and plateau atmospheric environment; The corrosion weight loss of 2A12-T6 aluminum alloy in the three environments shows a trend of increasing, which conforms to the power function, Moreover, the corrosion weight loss of 2A12-T6 aluminum alloy in marine atmospheric environment was far greater than that in cold and plateau atmospheric environment; The mechanical properties of 2A12-T6 aluminum alloy exposed to three kinds of environments showed an upward trend under the effect of natural aging at the initial stage, then decreased under the corrosion action of marine atmosphere with the extension of exposure time, and remained basically unchanged in cold and plateau atmosphere.

The high-temperature structure stability of high Al content Ni-based single crystal superalloy was studied, the microstructure was observed, and the micro-mechanism of the thermal stability of the material was analyzed. The results show that the exposure time and exposure temperature have significant effects on the stability of the alloy’s high-temperature structure. With the increase of exposure temperature and/or exposure time, the γ’ phase in the material becomes coarser, gradually connects and grows, and the stability of the material structure is obviously reduced. Compared with standard heat-treated alloys after high temperature exposure, The absolute value of the γ’ and γ phases misfit increases significantly. With the increase of exposure time, although the absolute value of the two-phase misfit continues to increase, the increase of its absolute value gradually slows down. The long-term structural stability of the alloy under continuous exposure to high temperature environment is good.

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