Phase (matter)

Magnesium alloy

Pure mathematics

6111 aluminium alloy

Metallurgy

Materials science

Galvanic corrosion

Galvanic cell

Pressing

Grain boundary

Grain size

Organic chemistry

Intergranular corrosion

Alloy

Mathematics

Microstructure

Composite material

Corrosion

Chemistry

Immersion (mathematics)

Corrosion Science

The microstructure of a commercial AZ91 Mg alloy was modified via equal channel angular pressing (ECAP) and subsequent aging. Immersion corrosion testing in 3.5 wt.% NaCl solution indicated that the ECAP alloy with heterogeneous grain structure had the best corrosion performance, which mainly stemmed from that the galvanic effect was weakened due to the reduced fraction and modified distribution of β phase particles. An aging treatment consisting of 60–90 h at 150 ℃ produced fine β phase precipitates which enhanced the micro-galvanic effect, such that the corrosion rates increased but were still lower than that of the as-cast alloy.

Corrosion behavior of AZ91 Mg alloy with a heterogeneous structure produced by ECAP