力學(xué)性能的影響
(1. 太原理工大學(xué) 材料科學(xué)與工程學(xué)院, 太原 030024；
2. 山西電力科學(xué)研究院, 太原 030001)
摘 要: 采用X射線衍射、 高分辨透射電鏡等現(xiàn)代分析測試手段研究了AlP中間合金變質(zhì)處理對AZ91+0.7%Si合金的顯微組織和力學(xué)性能的影響。研究結(jié)果表明： AZ91+0.7%Si合金中加入一定量的Al-P中間合金變質(zhì)處理后， Mg2Si的形貌發(fā)生了顯著變化， 由漢字狀變?yōu)榧毿〉念w粒狀， 其顆粒的平均尺寸為6~10 μm， 且基體組織的平均晶粒尺寸由原來的100 μm減小到45 μm左右， β-Mg17Al12相出現(xiàn)不同程度的斷網(wǎng)，從而使AZ91+0.7%Si合金的力學(xué)性能得到顯著提高。 說明Al-P中間合金對Si合金化的AZ91鎂合金具有很好的變質(zhì)強化功效， 是一種Mg2Si化合物的強化粒化劑。
關(guān)鍵字: 合金化AZ91; Mg2Si； 顯微組織； Al-P中間合金； 變質(zhì)處理； 力學(xué)性能
mechanical properties of Si alloying AZ91
magnesium alloys
XU Chun-xiang1, HAN Fu-yin1
（1. College of Materials Science and Engineering,
Taiyuan University of Technology, Taiyuan 030024, China;
2. Shanxi Electric Power Research Institute, Taiyuan 030001, China）
Abstract: The microstructures and mechanical properties of AZ91 containing 0.7% Si alloys modified by Al-P master alloy were observed using XRD and TEM. The results show that addition of certain amount Al-P master alloy into AZ91 containing 0.7% Si alloys leads to morphology change of Mg2Si phase from Chinese script to fine particle with the average particle size between 6 and 10 μm. The average grain size of the matrix reduces from 100 μm to 45 μm. The morphology of β-Mg17Al12 phase varys from continuous nets to discontinuous nets. Consequently, the mechanical properties of AZ91 containing 0.7% Si alloys are improved dramatically. It indicates that the Al-P master alloy has excellent modifying and strengthening effects on AZ91 containing 0.7% Si alloys and is a effective graining additive.
Key words: alloying AZ91; Mg2Si; microstructure; Al-P master alloy; modification; mechanical properties
