添加合金元素對鎂鋰合金機械性質與抗蝕性之影響

Effects of Alloy Additives on the Mechanical and Corrosion-Resistant Properties of Mg-Li Alloys

曾郁文(Y. W. Tseng) ； 王盈琁(Y. H. Wang) ； 江承祖(C. C. Chiang) ； 楊智富(C. F. Yang)

《鑛冶：中國鑛冶工程學會會刊》 54卷2期 (2010/06) Pp. 130-137

https://doi.org/10.30069/MM.201006.0011

摘要

本研究藉由光學顯微鏡（OM）、掃描式電子顯微鏡（SEM）、X光繞射儀（XRD）、微硬度試驗機、拉伸試驗機及恆電位儀，來探討Mg-8 Li（L8）、Mg-8 Li-2 Al （LA82）、Mg-8 Li-2 Al-0.3 Mn（LAM820）、Mg-8 Li-2 Al-0.3 Zr（LAK820）、Mg-8 Li-2 Al-0.3 Cr （LAR820）、Mg-8 Li-2 Al-0.3 Zr-0.3 Cr-0.3 Mn（LAMKR82000）六種雙相鎂鋰合金之機械性質與抗腐蝕性；研究結果顯示，添加2wt% Al之LA82合金經固溶、淬水後，合金之β相會因室溫時效而析出AlLi相，使合金呈現析出強化之效果，使其室溫拉伸強度及品質指數皆明顯優於L8合金。若在LA82合金內微量添加0.3%之Mn、Zr、Cr等過渡金屬元素 時，Mn可提升合金α相加工強化之效果，但對於β相並無幫助。Zr可稍微提升合金β相之強度，及合金α相和β相之加工強化效果，並可使合金β相高溫強度稍為提升。添加Cr可使合金β相強度獲得較明顯提昇，並使合金β相具較佳加工強化效果，且對提升合金β相高溫強度之效果較為顯著。於3.5wt% NaCl水溶液中抗蝕性測試結果顯示，在L8合金中添加2 wt% Al可改善L8合金之抗蝕性，而微量添加過渡金屬元素Mn、Zr、Cr對合金提升抗蝕性幫助不明顯，須藉由同時添加多種元素於合金中，提升抗蝕性效果才較明顯。

關鍵字

鎂鋰合金 ； 拉伸強度 ； 抗蝕性質

並列摘要

In this study we investigated the effects of alloy additives (Al, Mn, Zr, and Cr) on the mechanical and corrosion-resistant properties of Mg-Li Alloys. We used OM, SEM, XRD, micro-hardness tester, tensile tester and potentiostat to determine the mechanical and corrosion-resistant properties of Mg-8 Li (L8), Mg-8 Li-2 Al(LA82), Mg-8 Li-2Al-0.3 Mn (LAM820), Mg-8 Li-2 Al-0.3 Zr (LAK820), Mg-8 Li-2 Al-0.3 Cr (LAR820) and Mg-8 Li-2 Al-0.3 Mn-0.3 Zr-0.3 Cr (LAMKR82000) alloys. Results showed that the addition of 2 wt% Al in L8 alloy improved the tensile strength by forming AlLi precipitates in the β phase of the Al-bearing LA82 alloy. The addition of Mn, Zr, and Cr elements in the LA82 alloy also showed some improvements in the mechanical strength. Mn enhances the work hardening effect of α phase. Zr improves lightly the hardness of β phase and the work hardening effect in both α and β phases. Cr improves the hardness of β phase and the work hardening effect of β phase. Results of polarization curve in 3.5 wt% NaCl solution showed that the additions of 2 wt% Al, 0.3 wt% Mn, 0.3 wt% Zr and 0.3 wt% Cr in L8 alloys all produced an improvement in the corrosion resistance of the alloy. The LAMKR82000 alloy with the highest content of solute addition exhibited the best corrosion resistance among the Mg-Li alloys studied.

並列關鍵字

Mg-Li alloys ； Tensile strength ； corrosion resistance