School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001 China;
School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001 China;
Beijng Xinghang Mechanical Electrical Equipment Factory Beijing 100074 China;
School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001 China;
Al-3Ti-1B master alloy; processing parameters; grain refinement; Al-7Si alloy;