铸态ＲＦｅＣ样品快淬后处于一种亚稳态，自由能比铸态高，从而在较低温度下退火就能完成固相反应。对于等温退火过程，本文从其Ｊ－Ｍ－Ａ方程出发，论述了淬态退火形成四方相时间要短，并从理论上详细分析了快淬样品退火时三个特征温度随淬速的变化规律。 The as-cast RFeC samples are in a metastable state after quenching, and the free energy is higher than that of the as-cast, so that the solid phase reaction can be completed by annealing at a lower temperature. For the isothermal annealing process, starting from the J-M-A equation, this paper discusses that the quenching time of annealing to form a tetragonal phase is short, and the variation of the three characteristic temperatures with the quenching speed in quenching samples is theoretically analyzed in detail .