Transformation of Mechanical Performance and Corrosion Susceptibility of Al-Zn-Mg Alloy through Varied Flame Rectifications
Shuai Li *
School of Mechanical Engineering, North China University of Water Resources and Electric Power, Zhengzhou, 450045, China and School of Materials Science and Engineering, Dalian University of Technology, Dalian, 116024, China.
Shuaizhe Ai
School of Mechanical Engineering, North China University of Water Resources and Electric Power, Zhengzhou, 450045, China.
Dan Guo
School of Materials Science and Engineering, Dalian University of Technology, Dalian, 116024, China.
Dejun Yan
CSSC Huangpu Wenchong Shipbuilding Company Limited, Guangzhou, 510715, China.
Hao Lu
School of Materials Science and Engineering, Xi’an shiyou University, Xi’ an 710065, China.
Guoshun Yang
Aerospace Engineering Equipment (Suzhou) Co. Ltd., Suzhou, 215004, China.
Rongzheng Xu
School of Materials Science and Engineering, Shenyang Aerospace University, Shenyang, 110136, China.
Chuanqing Liao
Shanghai Aerospace Equipments Manufactureer Co., Ltd., Shanghai 200245, China.
Ningning Li
School of Mechanical Engineering, North China University of Water Resources and Electric Power, Zhengzhou, 450045, China.
Yonggang Jiang
CSSC Huangpu Wenchong Shipbuilding Company Limited, Guangzhou, 510715, China.
*Author to whom correspondence should be addressed.
Abstract
The mechanical properties and corrosion performance of Al-Zn-Mg alloy through varied flame rectifications was studied based on the intergranular corrosion, exfoliation corrosion experiment. The results showed that the flame rectification accelerated the corrosion susceptibility of Al-Zn-Mg alloy. And the maximum intergranular corrosion depth are detected with the value of 89 mm after three time of flame rectification. The tensile strength of Al-Zn-Mg alloy increased to 383 MPa after one time of flame rectification in 300 °C. Then there is no significant change of tensile strength of Al-Zn-Mg alloy with the increase of flame rectification times. The change of corrosion resistance of Al-Zn-Mg alloy with varied flame rectifications is mainly associated with the transformation of precipitates and grains. There is a notable increase in the precipitation of phases within the grains after one time of flame rectification at 300°C. However, after two times of flame rectification, a phenomenon of "redissolution" of precipitated phases occurs. After three times of flame rectification, small-sized new grains appear at the grain boundaries of the elongated grains within the correction area, which is the result of incomplete recrystallization in the alloy.
Keywords: Al-Zn-Mg alloy, flame rectification, microstructure, mechanical properties, corrosion performance