固溶温度及SiC含量对粉末冶金SiC/Al-Mg基复合材料组织与性能的影响

Effect of solution temperature and SiC content on microstructure and properties of PM SiC/Al-Mg-Cu-Fe-Sn composites

以SiC颗粒为增强体,Al-Mg-Cu-Fe-Sn合金作为基体合金,采用真空热压再热挤压的方法制备SiC/Al-Mg基复合材料,然后进行固溶和时效热处理,通过扫描电镜观察热压与挤压态材料的形貌,测试时效态材料的维氏硬度、拉伸性能,并进行电化学腐蚀实验,研究固溶温度及SiC颗粒含量(体积分数,下同)对该复合材料的显微组织与性能的影响。结果表明:随SiC颗粒含量增加,SiC/Al-Mg其复合材料的抗拉强度明显提高,材料在拉伸过程中的Serration现象减弱,10%SiC/Al-Mg基复合材料的屈服强度从基体合金的57 MPa提高到246 MPa,而伸长率从23.5%降低到6.0%。随固溶处理温度从400℃升高到570℃,材料的硬度先升高后降低,在固溶温度为500℃时,10%SiC/Al-Mg基复合材料的硬度HV达到92。粉末冶金SiC/Al-Mg基复合材料的腐蚀行为除了受SiC含量影响外,还与固溶温度有关。

The SiC particle reinforced Al-Mg-Cu-Fe-Sn composites were fabricated by hot-pressing and hot extrusion. The solution and aging treatments were then performed on the composites. The effects of the solution temperature and SiC particle content on the microstructure, mechanical properties and corrosion behavior of SiC/Al-Mg composites alloy were studied using scanning electron microscopy, Vickers hardness, tensile testing and electrochemical experiments. The results show that increasing the SiC particle contents can improve the tensile strength, and decrease the serration phenomenon of the composite. The yield strength of 10%SiC/Al-Mg composite increases from 57 MPa to 246 MPa, and the elongation decreases from 23.5% to 6.0%. With the increase of the solution temperature from 400 ℃ to 570 ℃, the Vickers hardness of SiC reinforced Al-Mg-Cu-Fe-Sn composite increases first, and then decreases. The maximum Vickers hardness of the 10% SiC/Al-Mg-Cu-Fe-Sn composite is 92 after the solution treatment at 500 ℃ and then aging. The corrosion behavior of the composite is affected by SiC particle content and the solution temperature.