( 1. 中南大學(xué) 材料科學(xué)與工程學(xué)院, 長(zhǎng)沙 410083;
2. 福州大學(xué) 機(jī)械工程學(xué)院, 福州 350002)
摘 要: 通過(guò)真空感應(yīng)爐中氬氣保護(hù)， 在ZM5熔體中加入Si獲得原位反應(yīng)自生Mg2Si/ZM5復(fù)合材料。 采用金相顯微鏡、 環(huán)境掃描電鏡、 拉伸實(shí)驗(yàn)等研究了Ca對(duì)該材料組織與性能的影響規(guī)律。 結(jié)果表明： Ca的加入改變了Mg2Si/ZM5復(fù)合材料中Mg2Si相的形貌， 使其從不規(guī)則的漢字狀變成較細(xì)小的多角形， 從而改善了材料的力學(xué)性能； 當(dāng)加入0.05%Ca(質(zhì)量分?jǐn)?shù))時(shí)， 復(fù)合材料的室溫力學(xué)性能最好， 屈服強(qiáng)度提高了10.4%， 延伸率提高了52.4%; 在200 ℃高溫下， 當(dāng)含Ca 0.05%～0.10%(質(zhì)量分?jǐn)?shù))時(shí)其屈服強(qiáng)度和延伸率最好, 分別提高了30.1%和92.3%。
關(guān)鍵字: 鎂合金； 金屬基復(fù)合材料； 力學(xué)性能； 原位反應(yīng)； Ca變質(zhì)
（ 1. School of Materials Science and Engineering,
Central South University, Changsha 410083, China;
2. School of Mechanical Engineering, Fuzhou University,
Fuzhou 350002, China）
Abstract: The in-situ Mg2Si/ZM5 magnesium matrix composite was fabricated by adding Si into the molten ZM5 magnesium alloy under argon atmosphere in vacuum induction furnace. The effects of Ca on microstructure and mechanical properties of in-situ Mg2Si/ZM5 magnesium matrix composite were investigated by opitical microscope, environmental scanning electron microscope, tensile test machine, etc. It is found that with the increasing Ca addition in composites, Mg2Si is transformed from a irregular Chinese script morphology to fine granular morphology, thus improving the mechanical properties of the material. When Ca addition is about 0.05%(mass fraction), excellent properties can be obtained, i.e., the increase of yield strength and elongation of the material is about 10.4% and 52.4%, respectively. At 200 ℃, when Ca addition is about 0.05%-0.10%(mass fraction), the yield strength and elongation of the material can reach the highest values, the extent of increase is about 52.4% and 92.3%, respectively.
Key words: magnesium alloy; metal matrix composite; mechanical property; in-situ reaction; Ca modification
