中文摘要：

采用优化的SC＋HDDR工艺制备了Nd15Fe78B7磁粉，分别研究了SC铸片的热处理温度及时间对HDDR磁粉性能的影响。研究结果表明，在热处理时间一定时，磁粉的矫顽力He和剩磁Br均随热处理温度的升高先增大后减小。热处理温度一定时，He和Br均随热处理时间的增加先增大后减小。当热处理温度及时间分别为1050℃和3h时，磁粉的矫顽力He和剩磁Br均达到最大值890kA／m和1．1T，其最大磁能积为241kJ／m^3。

英文摘要：

The effects of heat treatment temperature and time on magnetic properties of HDDR Nd15Fe78B7 magnetic powders prepared by SC＋HDDR modified process were studied. The results showed that for a determined heat treatment time, both the coercivity Ho and the remanence Br increase first, reach the maximum and then decrease with the increasing of heat treatment temperature. When the heat treatment temperature is determined, both Ho and Br increase first, reach the maximum and then decrease with the increasing of heat treatment time. He and Br of magnetic powders reach the maximum 890 kA/m and 1.1 T, and the maximum magnetic energy product achieves 241 kJ/m^3 while the heat treatment tem- perature and time are 1 050 ℃ and 3 h respectively.