(西安理工大學(xué) 材料科學(xué)與工程學(xué)院, 西安 710048)
摘 要: 采用普通凝固技術(shù)制備了鎂合金穩(wěn)定態(tài)準(zhǔn)晶相。 通過(guò)光學(xué)顯微鏡、 X射線(xiàn)衍射、 掃描和透射電子顯微分析, 確定了準(zhǔn)晶的組織、 相成分及結(jié)構(gòu)。 實(shí)驗(yàn)結(jié)果發(fā)現(xiàn): Mg-Zn-Y三元合金在室溫冷卻過(guò)程中, 準(zhǔn)晶相直接從液相形核、 長(zhǎng)大; 當(dāng)合金成分為Mg74Zn25Y1時(shí), 凝固組織為MgZn基體相、 析出相為α-Mg固溶體及二十面體Mg30Zn60Y10準(zhǔn)晶相; 當(dāng)x(Y)為2%、 3%時(shí), 合金中出現(xiàn)共析組織。
關(guān)鍵字: 準(zhǔn)晶; 二十面體; 鎂合金; 凝固
(School of Materials Science and Engineering,
Xi′an University of Technology, Xi′an 710048, China)
Abstract: Stable icosahedral Zn60Mg30Y10 quasicrystals was prepared by as-cast method. The microstructure, composition and phases of the as-cast Mg-Zn-Y alloy are analyzed by optical microscope, SEM and EDS. The constituent phases are identified by XRD, and the quasicrystal structure is identified by TEM. Analyzing results show that the i-phases directly nucleate and grow from melt of cooling Mg-Zn-Y ternary alloys; the microstructures of the Mg74Zn25Y1 alloy consist of α-Mg, MgZn and i-phase. When the mole fraction of yttrium reach 2% and 3%, the eutectoid microstructures are found in the Mg-Zn-Y alloys.
Key words: quasicrystal; icosahedral; magnesium alloy; solidification


