(1. 上海交通大學(xué) 輕合金精密成型國家工程研究中心，上海 200240；
2. 上海交通大學(xué) 金屬基復(fù)合材料國家重點實驗室，上海 200240)
摘 要: Mg-Gd系合金的時效析出強(qiáng)化效果優(yōu)異且析出序列及析出相在含稀土鎂合金中具有一定代表性。總結(jié)了國內(nèi)外Mg-Gd系合金時效析出的研究進(jìn)展，闡述該系合金的時效析出動力學(xué)、析出序列及析出相、析出相強(qiáng)化機(jī)理等。影響Mg-Gd系合金時效析出動力學(xué)的主要因素有時效溫度、Gd元素含量、晶粒尺寸、預(yù)變形量以及少量非稀土合金元素的添加等。Mg-Gd、Mg-Gd-Y(Dy)、Mg-Gd-Nd(Sm)等合金系的時效析出序列依次為β″-Mg3Gd→β′-Mg7Gd→β1-Mg3Gd→β-Mg5Gd，Mg-Gd-Zn合金時效過程中則還會有γ″-Mg70Gd15Zn15相和γ′-MgGdZn相存在。最后，對該系合金的析出強(qiáng)化機(jī)制和未來的發(fā)展方向進(jìn)行了闡述。
關(guān)鍵字: Mg-Gd系合金；時效析出動力學(xué)；析出相；力學(xué)性能；強(qiáng)化機(jī)制
（1. National Engineering Research Center of Light Alloy Net Forming,
Shanghai Jiao Tong University, Shanghai 200240, China;
2. Key State Laboratory of Metal Matrix Composite, Shanghai Jiao Tong University, Shanghai 200240, China）
Abstract:Mg-Gd alloys have an excellent ageing precipitation strengthening effect, their precipitation sequence and precipitate phases are also very typical in magnesium alloys containing rare earth elements. The research progress on ageing precipitation of Mg-Gd alloys was reviewed in three aspects: ageing precipitation kinetics are ageing temperature, Gd contents, grain size, different deformation, little addition amount of RE element. The precipitation sequence of Mg-Gd, Mg-Gd-Y(Dy), Mg-Gd-Nd(Sm) series alloys during ageing is basically β″-Mg3Gd→β′-Mg7Gd→ β1-Mg3Gd→β-Mg5Gd, there are also precipitates γ″-Mg70Gd15Zn15 and γ′-MgGdZn in Mg-Gd-Zn alloy. At last, the precipitation strengthening mechanism and further development of Mg-Gd alloys were discussed.
Key words: Mg-Gd alloys; ageing precipitation kinetics; precipitate; mechanical property; strengthening mechanism
