(山東大學 材料液態(tài)結構及其遺傳性教育部重點實驗室，濟南 250061)
摘 要: 結合LSM法和MCR法原位反應生成TiB2粒子增強Al-Si-Mg復合材料。研究發(fā)現(xiàn)：原位生成TiB2粒子呈等軸狀且尺寸<1μm，大都均勻分布在共晶組織中，與共晶Si交織在一起，在α(Al)中只有少量的TiB2粒子；原位TiB2粒子可明顯強化Al-Si-Mg復合材料，且隨著TiB2粒子數(shù)量的增加，強化效果也隨之提高，而且延伸率也略有升高，如6%TiB2/ZL104復合材料室溫拉伸強度可達296MPa，延伸率為5.5%；熱處理(T6 )可將共晶Si由原先的連續(xù)棒狀變?yōu)楣铝⒌念w粒狀，大幅度提高材料抗拉強度，使6%TiB2/ZL104復合材料室溫拉伸強度達386MPa，而材料仍屬于韌性材料。
關鍵字: TiB2/Al-Si-Mg復合材料； 原位反應； 顯微組織； 力學性能
of in-situ TiB2/Al-Si-Mg composites
（The Key Laboratory of Liquid Structure and Heredity of Materials,
Ministry of Education，Shandong University, Jinan 250061, P.R.China）
Abstract: In-situ TiB2 particulate reinforced Al-Si-Mg composites were fabricated by combining LSM method with MCR method. It is found that the shape of the in situ TiB2 particles is equaxed, their size is less than 1μm, most of them uniformly distribute in eutectic structures and are interlaced with eutectic Si, and there is a few of TiB2 particles in α(Al). It is also found that TiB2 particles can enhance the tensile strength of the composites, and with TiB2 particles increasing the degree of enhancement is increased and the ductility is also raised slightly. For example, the tensile strength of 6%TiB2/ZL104 composites is as high as 296MPa, and its ductility is 5.5%. Heat treatment can change the eutectic Si from continuous rod-like to isolated particle-like and increase the tensile strength of the composites considerably. The tensile strength of 6%TiB2/ZL104 composites after heat treatment can be enhanced to 386MPa, however the composites after heat treatment also belong to plastic material.
Key words: TiB2/Al-Si-Mg composites; in-situ reaction; microstructure; mechanical properties
