Positron annihilation spectroscopy investigation of hot-extruded Al-20Si-0.35RE alloy
Positron annihilation spectroscopy is a nondestructive evaluation method which is sensitive to study the microdefects of materials. In this article, hypereutectic Al-20Si-0.35RE (wt.％) pre-alloyed powders was synthesized by using the water atomization method. The pre-alloyed powders were subsequently hot extruded with pressure of 250~500 MPa at 300oC. The effect of pressure of hot-extrusion on the evolution of microdefects in Al-20Si-0.35RE alloy was investigated by positron annihilation spectroscopy, electrical conductivity tests and hardness tests. It was shown that the accretion of pressure led to an apparent increase in conductivity and microhardness. For all samples, the hot-extrusion causes a pronounced change in positron annihilation related parameters signaling the variation of microdefects. The results of hardness tests and the electrical conductivity tests are varied following with the positron annihilation spectroscopy. Possible mechanisms of the influence of hot-extrusion on the behavior of microdefects are discussed.
Hypereutectic Al-Si alloy Positron annihilation Hot-extrusion Conductivity
Yuxin Wang Biao Yan Wei Gao Yu Zhang Wenjun Liao Weiwei Chen Wei Lu
School of Materials Science and Engineering, Tongji University, Shanghai 200092, China Department of School of Materials Science and Engineering, Tongji University, Shanghai 200092, China Department of Chemicals & Materials Engineering, The University of Auckland, PB 92019,Auckland, New
国际会议
11th IUMRS International Conference in Asia(第十一届国际材联亚洲材料大会 IUMRS-ICA 2010)
青岛
英文
400-406
2010-09-25（万方平台首次上网日期，不代表论文的发表时间）