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采用JSL－500区域熔化真空定向凝固装置，对TbDyFe超磁致伸缩合金定向凝固轴向择优取向、组织和磁致伸缩性能的研究表明：温度梯度GL≈700K／cm基本不变的条件下，当晶体生长速度V1mm／min时，晶体以平面晶方式生长；16mm/min时，以胞状晶方式生长；V=8─12mm／min时，晶体按胞核晶方式生长（胞状晶向树枝晶转变的初始阶段）；当V＞15mm／min时，晶体按发达的树枝晶方式生长．保持V＝12mm／min不变，当GL≈1000K／cm时，晶体又以胞状品方式生长；GL≈400K／cm时，以发达的树枝晶方式生长平面晶和胞状晶生长的样品，其轴向择优取向为＜110＞取向，磁致伸缩没有压力效应，性能偏低；胞枝晶方式生长的样品轴向择优取向为＜112＞取向，磁致伸缩性能优越，10MPaN压应力下，平行于外磁场方向的饱和磁致伸缩系数λ最大值达到0．00175；发达树枝晶生长的样品，轴向＜112＞择优取向程度减弱，磁致伸缩性能下降。
Using JSL-500 regional melting vacuum directional solidification device, the directional orientation solidification and the microstructural and magnetostrictive properties of TbDyFe giant magnetostrictive alloy were studied. The results show that under the condition of temperature gradient of GL≈700K / cm, When the crystal growth rate is V1mm / min, the crystal grows in the plane-crystal mode; when the crystal growth rate is 16mm / min, it grows in the form of cell-like crystals; when V = 8─12mm / Initial stage); when V> 15mm / min, the crystal grows according to developed dendrites. Maintaining V = 12mm / min unchanged, when GL ≈ 1000K / cm, the crystal cells in order to cell growth; GL ≈ 400K / cm, the developed dendritic growth plane crystal and cell growth of the sample, the axis Magneostriction does not have the effect of pressure and the performance is low. The preferred axial orientation of the samples grown by dendrites is <112> orientation, and the magnetostrictive properties are superior. Under the compressive stress of 10 MPaN, The maximum value of the saturation magnetostriction coefficient λ in the direction of the external magnetic field reaches 0.00175. The dendrites grown in developed dendrites show a decrease in the preferred orientation in the axial direction <112> and the magnetostriction.