搅拌摩擦加工技术对高硅铝合金拉伸性能的影响分析

Effect of Friction Stir Processing Technology on Tensile Properties of High Silicon Aluminum Alloy

研究了搅拌摩擦加工(FSP)技术对高硅铝合金Al Si30的抗拉强度、伸长率的影响,探讨了其断裂机理。结果表明,随着摩擦搅拌道次的增加,Al Si30的强度和塑性都显著提高,材料的断裂模式从脆性断裂转变为韧性断裂。当摩擦搅拌道次较少时,粗大硅相多,且不够圆整,裂纹首先发源于粗大硅颗粒内部,并引发基体断裂,硅相的断裂面与周围基体的断裂面平齐;当摩擦搅拌道次较多时,粗大硅相少,而且圆整,裂纹基本上发源于粗大硅颗粒/铝基体界面。

The effects of friction stir processing （FSP） technology on the tensile strength and elongation of high silicon aluminum alloy AlSi30 were studied. The fracture mechanism was discussed. The results show that with friction stirring passes increasing, the strength and plastic of AlSi30 significantly improve, the fracture mode of the material changes from brittle fracture to ductile fracture. When the friction stir passes are low, thick silicon phases increase, which are not round. The crack first originates in thick silicon particles, which can lead to the fracture of matrix, the fracture surface of silicon phase and the substrate around is abreast. When the friction stir passes are more, thick silicon phases decrease, which is round, the crack basically originates from the interface of thick silicon particles/Al matrix.