The <100> oriented Fe83Ga17 alloy rods with various NbC contents less than 1at% were prepared by the directional solidification method at a growth rate of 720 mm·h-1. Low NbC-content was found to affect the oriented grain growth and slightly improve the <100> orientation. Flat grain boundaries in the alloys with low NbC contents less than 0.2at% became greatly curved at higher NbC contents, and a large amount of Nb-rich precipitates were observed in the alloys with high NbC contents. Small amounts of NbC, less than 0.2at%, resulted in an increase in magnetostrictive strain due to the improvement of the <100> orientation, and a high magnetostrictive strain value of 335×10-6 under a pre-stress of 15 MPa was obtained in the 0.1at% NbC-doped alloys. The magnetostrictive performance obviously decreased with the NbC addition higher than 0.5at%, and the strain sensitivity under no pre-stress was lower than that in the binary Fe-Ga alloy.
The <100> oriented Fe83Ga17 alloy rods with various NbC contents less than 1at% were prepared by the directional solidification method at a growth rate of 720 mm·h-1. Low NbC-content was found to affect the oriented grain growth and slightly improve the <100> orientation. Flat grain boundaries in the alloys with low NbC contents less than 0.2at% became greatly curved at higher NbC contents, and a large amount of Nb-rich precipitates were observed in the alloys with high NbC contents. Small amounts of NbC, less than 0.2at%, resulted in an increase in magnetostrictive strain due to the improvement of the <100> orientation, and a high magnetostrictive strain value of 335×10-6 under a pre-stress of 15 MPa was obtained in the 0.1at% NbC-doped alloys. The magnetostrictive performance obviously decreased with the NbC addition higher than 0.5at%, and the strain sensitivity under no pre-stress was lower than that in the binary Fe-Ga alloy.
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