Study on the Intergranular Corrosion Behavior of Welding Joint of A7N01-T4 Al-Alloy for High-Speed Train
This paper studied the intergranular corrosion behavior of A7N01-T4 Al-alloy and its welding joint through corrosion rate test by chemical analysis and morphology observation by metalloscope, LCSM and element analysis by EDS. The results showed that the corrosion rate of welding joint was higher than that of the base, and HAZ was the worst corrosion part of welding joint. Zn2Mg strengthening phase of HAZ segregated continuously along grain boundary under the affected of heat-input of welding, and the low potential of this zinc-rich phase made it to be anode in corrosion cell and dissolved preferentially, an active corrosion route along grain boundary was formed, which made further corrosion develop into inner alloy.
Xiaoming Sang, Pengcheng Wang, Liqun Ai, Yungang Li and Jinglong Bu
X. M. Wang et al., "Study on the Intergranular Corrosion Behavior of Welding Joint of A7N01-T4 Al-Alloy for High-Speed Train", Advanced Materials Research, Vols. 284-286, pp. 1594-1597, 2011