Effects of electric pulse modification with different technique parameters on the liquid structure of pure aluminum
The modification of liquid metal by electric pulse (EP, EPM) is a novel method for grain refinement. In this study, based on the reported structural heredity of EP-modified liquid aluminium, the structure tests of EP-modified liquid aluminium with different technique parameters were conducted by using high temperature X-ray diffractometer. The results show that the quantitative structure changes of EP-modified liquid aluminium have a close relationship with the modifying time and modifying temperature. The decrease of modifying time could result in an obvious weaker principal peak in structure factor curve compared with the optimal EP technique parameters, but a slight increase of coordination number (Ns), correlation radius (rc) and average atom number per cluster (Nat) is still observed under this condition. These facts indicate that the EP-modified liquid aluminum could gain an increasing order degree, and thus have an advantage during the formation of a stable nucleus, eventually leading to a grain-refining solidification structure. On the other hand, the structure factor curve of EP-modified liquid aluminum at the high modifying temperature of 850℃ tends to be overlapped with that of the unmodified during the principal peak range. In this case, the competition result between the EP strengthening effect and the destruction of superheating would determine the final structure of EP-modified liquid aluminum.
Electric pulse modification liquid aluminum X-ray diffraction atomic cluster superheating
Jingang Qi Jianzhong Wang Bing Wang LiJia He Huiling Du
Department of Material and Chemical Engineering, Liaoning University of Technology, Jinzhou 121001, School of Metallurgical & Ecological Engineering, University of Science & Technology Beijing, Beijin
国际会议
青岛
英文
203-206
2009-10-09（万方平台首次上网日期，不代表论文的发表时间）