Secondary phase precipitation and thermally stable microstructure refinement induced by ECAP on Mg-Y-Nd (WN43) alloy
Abstract
Magnesium alloy Mg-4Y-3Nd (WN43) was subjected to ECAP at T similar to 300 degrees C up to 8 passes, using route B-C. The initial as-extruded material with average grain size of similar to 10 mu m, was effectively refined down to sub-micrometer scale, reaching a grain size of similar to 380 nm, after 8 passes.
At the same time, secondary phase particle precipitation of beta'-Mg12Nd2Y, and beta-Mg14Nd2Y was induced. At 8 passes, fragmentation and coarsening of these phases occurred.
Both grain refinement and beta'/beta precipitation strengthened the alloy. The strengthening was detected by nanoindentation hardness and accounted of up to 30% increment at 8 ECAP pass, compared to the initial extruded condition. (C) 2018 Elsevier B.V.
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