摘要
采用离心铸造法制备了原位Mg2Si/Al梯度复合材料,研究了初生相Mg2Si的梯度分布,研究了离心转速和磷变质对Mg2Si/Al梯度复合材料组织的影响及作用机理。结果表明,经过离心铸造,原位Mg2Si/Al梯度复合材料的Mg2Si增强相具有明显的U型梯度分布。离心转速越高,梯度分布越明显,相应层Mg2Si尺寸减小或碎化明显,最内层的初生Mg2Si的体积分数随之增加。磷变质的复合材料中,Mg2Si增强相呈现为细小块状,同时发现磷变质后,中间层的宽度由230μm增加到900μm左右。干滑动磨损实验发现,Mg2Si/Al梯度复合材料比HT200具有更优的耐磨性。
In situ Mg2Si/Al gradient composites were successfully prepared by centrifugal casting technique. The microstructures of unmodified and modified Mg2Si/Al composites showed significant gradient distribution along thickness under the same centrifugal speed. The effects of centrifugal speed and phosphorus modification on microstructures of Mg2Si/Al gradient composites were studied. The results show that, the microstructures of unmodified and modified Mg2Si/Al composites showed significant gradient distribution along thickness under the same centrifugal speed, namely, there were Mg2Si particulates reinforcement in both inside and outside wall and alloy matrix in the centre. As the centrifugal speed increases, the gradient distribution of Mg2Si became more obvious, the size of Mg2Si in the corresponding layer reduced obviously, and the volume fraction of primary Mg2Si in innermost layer increases. After modified by phosphorus, the microstructures of primary Mg2Si in each layer changed from dendrite to polygon. In addition, the thickness of intermediate layer changed obviously from 230 ixm to 900μm. In addition, the wear test results showed that the wear resistance of Mg2Si/Al gradient composite is far superior to that of HT200.
出处
《铸造》
CAS
CSCD
北大核心
2015年第8期747-753,共7页
Foundry
基金
吉林省科技发展计划项目(20070506)
