Effect of Nd and Dy Addition on AZ91D Ignition Temperature and Microhardness

Abstract:

Magnesium alloys are very active and readily ignite during heating and melting. In this study, the ignition-proof property of AZ91D with Nd and Dy addition was discussed, and the effects of these ignition-proof elements on the microstructure and microhardness of AZ91D investigated. The results show that the ignition-proof performance of magnesium alloy is improved obviously. The ignition resistance is attributed to the compact oxide films, which consist of MgO, Al₂O₃, Nd₂O₃, Dy₂O₃. When Dy content increased beyond 0.5%, the change tendency of ignition point of the alloy follows the shape of “v” curve, and the ignition point increased with Nd addition. The optimum composition of the newly developed magnesium alloy is AZ91D-3Nd-0.5Dy with the ignition point about 60K higher than AZ91D. And also AZ91D-3Nd-0.5Dy has fine microstructure and higher microhardness.

• Periodical: Materials Science Forum (Volume 788)
• Pages: 34-40
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.788.34
• Online since: April 2014
• Authors: Jian Ding*, Lin Qin, Yong Yan Li, Wei Min Zhao
• Keywords: AZ91D, Dy, Ignition, Microhardness, ND, Oxide Film

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