Gong Chunjie, Tu Hao, Wu Changjun, Wang Jianhua, Su Xuping
Jiangsu Key Laboratory of Materials Surface Science and Technology, Changzhou University, Changzhou 213164, China.
Jiangsu Collaborative Innovation Center of Photovoltaic Science and Engineering, Changzhou University, Changzhou 213164, China.
Materials (Basel). 2018 Mar 20;11(3):456. doi: 10.3390/ma11030456.
An hypereutectic Al-18Si alloy was modified via an Al-3B master alloy. The effect of the added Al-3B and the modification temperature on the microstructure, tensile fracture morphologies, and mechanical properties of the alloy were investigated using an optical microscope, Image-Pro Plus 6.0, a scanning electron microscope, and a universal testing machine. The results show that the size of the primary Si and its fraction decreased at first, and then increased as an additional amount of Al-3B was added. When the added Al-3B reached 0.2 wt %, the fraction of the primary Si in the Al-18Si alloy decreased with an increase in temperature. Compared with the unmodified Al-18Si alloy, the tensile strength and elongation of the alloy modified at 850 °C with 0.2 wt % Al-3B increased by 25% and 81%, respectively. The tensile fracture of the modified Al-18Si alloy exhibited partial ductile fracture characteristics, but there were more areas with ductile characteristics compared with that of the unmodified Al-18Si alloy.
通过Al-3B中间合金对过共晶Al-18Si合金进行变质处理。利用光学显微镜、Image-Pro Plus 6.0、扫描电子显微镜和万能试验机研究了添加的Al-3B及变质温度对该合金微观组织、拉伸断口形貌和力学性能的影响。结果表明，随着Al-3B添加量的增加，初生Si的尺寸及其体积分数先减小后增大。当Al-3B添加量达到0.2 wt%时，Al-18Si合金中初生Si的体积分数随温度升高而减小。与未变质的Al-18Si合金相比，在850℃下用0.2 wt% Al-3B变质处理的合金，其抗拉强度和伸长率分别提高了25%和81%。变质处理后的Al-18Si合金拉伸断口呈现部分韧性断裂特征，但与未变质的Al-18Si合金相比，具有韧性特征的区域更多。
