热变形Pr-Fe-B-Cu磁织构的形成机制及〔006〕织构的获得

Formation Mechanism of Magnetic Texture in Hot Deformed Pr Fe B Cu Magnets and the Achievement of the 006 Texture

本文提出Ｐｒ－Ｆｅ－Ｂ－Ｃｕ热压历程判据的计算式：ｆ（Ｔ，ε）＝Ｔ２２１１５３９．９ｌｇε＋１８９５７４８８。判据认为：在变形温度≥１１７３Ｋ时，ｆ（Ｔ，ε）＞１，则热压磁体的其它峰强比较小，Ｉ（００６）／Ｉ（１０５）≥０．６０；Ｉ（００６）／Ｉ（１０５）与变形量ε之间存在如下关系式：Ｉ（００６）／Ｉ（１０５）＝０．９８３ε＋０．４６５；分析了｛１０５｝成为主滑移系的原因。在Ｔ＜１１７３Ｋ，ｆ（Ｔ，ε）＞１时，首次得到热压Ｐｒ－Ｆｅ－Ｂ－Ｃｕ的〔００６〕织构，并讨论了〔００６〕织构的形成原因。当ｆ（Ｔ，ε）≤１，热压磁体均破断开裂，形成不完善的〔１０５〕织构。在热变形中，Ｐｒ２Ｆｅ１４Ｂ均存在严重的点阵畸变、原子错位，热处理后可恢复正常。

The formula of hot deformation process criterion has been put forward.That is f(T,)=T 2211539 9lg+1895748 8.It suggested that if f(T,)≤1, samples must break down at the beginning stage of hot deformation,and the effective strain is greatly lowered .If f>1,I (006) /I (105) is improved as the total strain ε is raised and other diffraction intensity ratio I/I Mas is decreased sharply. Under conditions of T≥1173 K,there esists a relationship: I (006) /I (105) =0 983ε+0 465. Remances of the magets are higher than those deformed in f≤1. Under the Conditions of T<1173 K and f>1, 006 magnetic texture was obtained for the first time. At this temperature, stress of intercrystalline, Pr 2Fe 14 B, is lower than that of grain boundary, two phase eutectic. Lower is benificial to the sliding over (001) crystal face. For the grains that stopped sliding over {105}, they can be continuously slided over (001), thus the 006 texture are achieved. But {105} is adapt to the other conditions, such as, f(T,)≤1 and T≥1173K,whether f(T,ε)≤1 or >1. No matter what conditions, there exist lattice distortion, atom disorder and stacking fault in Pr 2Fe 14 B and grain boundary phase during deformation, which can all be eliminated by suitable heat treatment.