为了提高永磁体性能尤其是矫顽力，对气雾化MnAl粉末首次进行了30 s短时间球磨。结果表明，如此短的处理时间加上随后的退火可以高效地得到纳米结构和可控的相变。球磨过程中产生的微应变引起的缺陷与退火过程中形成的β相共同起到钉扎中心的作用，从而提高了矫顽力。研究表明，为了在磁化强度和矫顽力之间达到折中，在铁磁性τ-MnAl相和β相的形成之间找到一个平衡是很重要的。球磨（30 s）和退火后获得的矫顽力高达4.2 kOe (1 Oe = 79.6 A·m^–1)，与早期文献报道的球磨时间超过20 h时的矫顽力相当。球磨后粉末的退火温度降低了75 ℃，矫顽力提高了2.5倍，而退火后的气雾化材料的剩磁基本保持不变，为合成各向同性的MnAl基粉末开辟了一条新的途径。

An unprecedentedly short milling time of 30 s was applied to gas-atomized MnAl powder in order to develop permanent magnet properties and, in particular, coercivity. It is shown that such a short processing time followed by annealing results in efficient nanostructuring and controlled phase transformation. The defects resulting from the microstrain induced during milling, together with the creation of the β-phase during post-annealing, act as pinning centers resulting in an enhanced coercivity. This study shows the importance of finding a balance between the formation of the ferromagnetic τ-MnAl phase and the β-phase in order to establish a compromise between magnetization and coercivity. A coercivity as high as 4.2 kOe (1 Oe = 79.6 A·m^-1 ) was obtained after milling (30 s) and annealing, which is comparable to values previously reported in the literature for milling times exceeding 20 h. This reduction of the postannealing temperature by 75 ℃ for the as-milled powder and a 2.5-fold increase in coercivity, while maintaining practically unchanged the remanence of the annealed gas-atomized material, opens a new path for the synthesis of isotropic MnAl-based powder.