热处理对Fe81Ga19合金组织结构与磁致伸缩性能的影响

采用电弧熔炼法制备了Fe81Ga19合金多晶样品,研究了不同热处理工艺对合金组织结构及磁致伸缩性能的影响.样品经过700℃、800℃和900℃保温后采用空冷、炉冷和淬火3种冷却方式.结果显示,经过不同热处理后样品的微观组织均为单相bcc结构,而磁致应变从34×10-8到94×10-6不等;当热处理温度为800℃时,淬火处理后可获得较好的磁致伸缩性能(88×10-6),而热处理温度较高(900℃)时,采用炉冷的方式可获得较好的磁致伸缩性能(94×10-6).推测热处理方式和晶体取向对Fe81Ga19合金磁致伸缩性能有较重要的影响.

Effects of Heat-treatment on the Microstructure and Magnetostriction of Fe81Ga19

Button ingots of polycrystalline Fe81Ga19 alloy are prepared by arc-melter, and the effects of different heat-treatments on their microstructure and magnetostriction are investigated. The specimens are annealed at 700℃, 800℃, and 900℃, and then cooled at different speeds, i.e. quenching into ice water, air cooling, or furnace cooling. The results show that specimens after different heat-treatments all exhibit single bcc structure, but the magnetostrictions vary from 34×10-6 to 94×10-6; When the heating ternpemture is 800℃, good rnagnetostriction (88×10-6) can be obtained by quenching. On the other hand, when the specimen is heated at a higher temperature (900℃), furnace cooling is a better way to get good magnetostrietion (94×10-6). It is speculated that the heat-treatment temperature and the crystal orientation may be two primary factors influencing the magentostriction of Fe81Ga19 alloy.