添加Al及Mn對Mg-10Li合金之機械性質影響及微弧氧化對鎂鋰合金抗蝕性改善

Effects of Al and Mn additions on the Mechanical Properties of Mg-10Li Alloys and the Improvement of Corrosion Resistance in Micro-arc Oxidized of Mg-Li Alloys

余宗融(Zong-long Yu)

指導教授 ： 楊智富

大同大學/工程學院/材料工程學系所/碩士(2008年)

摘要

本研究藉由示差熱分析（DSC）、光學顯微鏡（OM）、掃瞄式電子顯微鏡/能量散佈光譜分析儀（SEM/EDS）、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-10 wt% Li（L10）、Mg-10 wt% Li-0.3wt% Mn（LM100）、Mg-10 wt% Li-2 wt% Al（LA102）及Mg-10 wt% Li-2 wt% Al-0.3 wt% Mn（LAM1020）等四種雙相鎂鋰合金之機械性質與抗腐蝕性質；研究結果顯示，經固溶及室溫48小時＋50℃48小時二階段時效之LA102及LAM1020合金室溫拉伸強度及品質指數已分別大於200 MPa及390 MPa，已足與一般結構用金屬相比擬，若施以30%之滾軋，強度均可大於220 MPa，其中LAM1020之強度甚至達240 MPa以上。於3.5 wt % NaCl水溶液中所測得之極化曲線顯示，於L10合金中添加0.3 wt% Mn所得之LM100可改善L10之抗蝕性，添加2 wt% Al 之LA102、LAM1020可再進一步提昇鎂鋰合金之抗蝕性；另一方面，四種鎂鋰合金利用微弧氧化之表面處理成膜後，抗蝕性皆較未成膜前佳；由此顯示，合金元素的添加及微弧氧化均可改善鎂鋰合金之抗蝕性，其中，微弧氧化之效果尤佳。

關鍵字

鎂鋰合金 ； 拉伸性質 ； 腐蝕性質 ； 微弧氧化

並列摘要

In this study room temperature mechanical and corrosion properties in Mg-10 wt% Li (L10), Mg-10 wt% Li-0.3 wt% Mn (LM100), Mg-10 wt% Li-2wt% Al (LA102) and Mg-10 wt% Li-2 wt% Al-0.3 wt% Mn (LAM1020) alloys are investigated by using DSC, OM, SEM/EDS, XRD, micro-hardness tester, tensile tester and potentiostat. The results showed that the room temperature tensile strengths and the quality indices of LA102 and LAM1020 alloys are greater than 200 MPa and 390 MPa, respectively, which are well qualified for structural applications. After 30% mechanical rolling, their tensile strengths are greater than 220 MPa, and the rolled LAM1020 alloy exhibits the highest tensile strength of 240 MPa. According to the result of polarization curve in 3.5 wt% NaCl solution it showed that the LM100 (containing 0.3 wt% Mn) is a better corrosion resistant alloy than the L10. Similarly, the addition of 2 wt% Al into L10 and LM100 alloys to produce LA102 and LAM1020 alloys results in an improvement in the corrosion resistance in the alloys. In addition to the alloying method, the application of a micro-arc oxidation treatment on the Mg-Li alloys to produce a protective ceramic layer proves to be very effective in improving the corrosion resistance.

並列關鍵字

Mg-Li alloys ； Tensile properties ； Corrosion behavior ； Micro-arc oxidation

參考文獻

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