Microstructure and nanohardness of Ti−48%Al alloy prepared by
rapid solidification under different cooling rates
rapid solidification under different cooling rates
(1. School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, China;
2. State Key Laboratory of Metastable Materials Science and Technology,
Yanshan University, Qinhuangdao 066004, China)
2. State Key Laboratory of Metastable Materials Science and Technology,
Yanshan University, Qinhuangdao 066004, China)
Abstract: The influence of cooling rate on the microstructure and nanohardness of the rapidly solidified Ti−48%Al alloys prepared by melt spinning method was studied. The results show that the microstructure of the rapidly solidified ribbons is refined and homogenized compared with that of the conventionally cast mother alloy. With increasing the cooling rate, the grain size decreases greatly. The relationship between the ribbon thickness and the wheel speed was examined, and the effect of the wheel speed on the cooling rate was also studied. It was found that the ribbon thickness decreases inversely with the wheel speed. The nanohardness increases with increasing cooling rate due to the grain size strength.
Key words: rapid solidification; microstructure; cooling rate; TiAl intermetallics