Effect of Compound Modification of Sr, B and RE on Microstructure and Properties of Al-30Si Alloy
Author of the article:WAN Hui;LI Xiaosong;LI Tielin;CAI Anhui;LUO Yun
Author's Workplace：College of Mechanical Engineering,Hunan Institute of Science and Technology,Yueyang 414000,China
Key Words：Sr-B-RE compound modification Al-30Si microstructure mechanical properties
Abstract：
The effect of compound modification of Sr, B and RE on microstructure and properties of Al-30 Si alloy was studied. The results show that the microstructure and morphology of the alloy change significantly after refinement and modification, and the dendritic groups of α(Al) phase disappeared and are transformed into equiaxed or columnar crystals.Primary silicon granules are refined and edges and corners are passivated. Acicular eutectic silicon becomes short rod-shaped or granular and evenly distributed. The tensile strength, elongation and hardness of the alloy increase by 55%and 66%, respectively. When RE content is 0.5~0.8%, the alloy exhibits better comprehensive mechanical properties.
