Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5460246 | Journal of Alloys and Compounds | 2017 | 20 Pages |
Abstract
The thermal expansion and thermal diffusion properties of FeâAl alloys were measured using dilatometric and laser flash methods. At two allotropic transformation temperatures, the length change of the rapidly solidified pure Fe by injection casting deviates from that of the pure Fe by heating-cooling processing in a dilatometer. The ferro-/paramagnetic transition and second order transition do not influence the thermal expansion behaviors of FeâAl alloys as temperature increases from 473 to 1373Â K. The thermal expansion coefficients of Fe70Al30, Fe60Al40 and Fe55Al45 alloys are apparently larger than those of Fe25Al75 and Fe90Al10 alloys. Once temperature exceeds 877Â K, the thermal expansion coefficients of Fe-Al alloys are enhanced with the increase of Al content, except for Fe25Al75 alloy owing to the large packing factor of FeAl3 crystal structure. In the temperature range from 309 to 877Â K, the thermal diffusivity as a function of temperature decreases in the sequence of Fe90Al10, Fe55Al45, Fe60Al40, Fe70Al30 and Fe25Al75, and their values are lower than that of pure Fe at the same temperatures. As temperature increases, the thermal diffusivity values of FeâAl alloys increase, except that of Fe90Al10 alloy decreases in the temperature range from 294 to 979Â K and then increases once temperature further increases to 1078Â K because of the ferro-/paramagnetic transition. Their thermal expansion coefficient and thermal diffusivity serve as linear or polynomial functions of temperature.
Related Topics
Physical Sciences and Engineering
Materials Science
Metals and Alloys
Authors
Y. Ruan, N. Yan, H.Z. Zhu, K. Zhou, B. Wei,