Corrosion resistance of 2195 aluminum alloy treated by multi-step-heating-rate controlled process
(1.北京市北京科技大学材料科学与工程学院
2.School of Materials Science and Engineering, Beijing University of Aeronautics and Astronautics,Beijing 100083, China)
2.School of Materials Science and Engineering, Beijing University of Aeronautics and Astronautics,Beijing 100083, China)
Abstract: 2195 aluminum-lithium alloy was widely applied in the aviation and aerospace industry, but it is highly susceptible to pitting and intergranular corrosion undergoing sever corrosive circumstance and moisture atmosphere. To solve this problem and consequently to prolong its service life, a multi-step-heating-rate(MSRC) process was carried out. Investigations were carried out to find the effect of the MSRC process on the alloys corrosion resistance. It is found that the MSRC process is more favorable for the uniform phase precipitation by comparing the corrosion resistance of samples treated by traditional heat treatments. The potential difference between phases can be reduced and intergranular corrosion is able to be prohibited efficiently. Besides, the rare earth infiltration is beneficial to improving the corrosion resistance. As heating time increases, the corrosion resistance declines gradually, samples treated by artificial aging and solid solution also exhibit a better corrosion resistance.
Key words: 2195 aluminum-lithium alloy; multi-step-heating-rate controlled process; corrosion resistance; rare earth