(1. 大連理工大學(xué) 材料科學(xué)與工程學(xué)院，大連 116024；
2. 大連理工大學(xué) 三束材料改性國(guó)家重點(diǎn)實(shí)驗(yàn)室，大連 116024)
摘 要: 利用電磁攪拌技術(shù)，結(jié)合懸浮鑄造方法，在澆鑄AZ61鎂合金的過(guò)程中加入微納米顆粒CaC2，使CaC2彌散分布于母相金屬液中，促進(jìn)合金形核，改善合金鑄造組織形態(tài)和分布，提高合金的力學(xué)性能。結(jié)果表明：利用電磁−懸浮鑄造制備的鎂合金，其顯微組織細(xì)化，晶間β相細(xì)小并且網(wǎng)狀結(jié)構(gòu)減少，當(dāng)CaC2懸浮劑加入量(質(zhì)量分?jǐn)?shù))為0.36%時(shí)，鎂合金的細(xì)化效果最佳，其晶粒最小尺寸為75 μm，抗拉強(qiáng)度為211.4 Pa，伸長(zhǎng)率為8.5%，與普通金屬型鑄造制備的鎂合金相比，晶粒尺寸減小64.3%；抗拉強(qiáng)度提高約24.2%；伸長(zhǎng)率提高46.6%。
關(guān)鍵字: AZ61鎂合金；CaC2；電磁−懸浮；顯微組織；力學(xué)性能
（1. School of Materials Science and Engineering, Dalian University of Technology, Dalian 116024;
2. State Key Laboratory of Materials Modification by Laser, Ion and Electron Beams,
Dalian University of Technology, Dalian 116024, China）
Abstract: The electromagnetic suspension casting of AZ61 wrought magnesium alloy was studied using electromagnetic stirring technique and the suspension casting during the casting process. The electromagnetic suspension casting not only can diffuse CaC2 powders distribution into the melt evenly, but also can refine the development of dendrite. The results show that electromagnetic suspension casting is found to be effective on refining the microstructure of magnesium materials, thinning the β-Mg17Al12 and improving the distribution uniformity of β-Mg17Al12 phase. The 0.36% CaC2 addition refines the grains most effectively, and the size is 75 μm. The ultimate tensile strength of alloys is 211.4 MPa, and the elongation is 8.5%. The grain size decreases by 64.3%, and the ultimate tensile strength and the elongation of alloys increase by 24.2% and 46.6% respectively compared with those of the die-casting Mg alloys.
Key words: AZ61 magnesium alloy; CaC2; electromagnetic suspension; microstructure; tensile properties
