铁-铬-钒三元系固态合金的量热研究

本文介绍一种自制环境等温型高温量热计, 其原理基于差热分析。在1300 K下所测纯铁等相变热与文献值吻合甚好, 证明仪器可靠。应用此仪器系统测量了Fe-Cr-V三元系九种不同成份的α-合金生成焓, 以及它们的α-α相变焓。为该体系的热力学研究提供了一些必要的热化学数据。

THE CALORIMETRY STUDY OF Fe-Cr-V SOLID ALLOY SYSTEMS

A differential calorimeter which operates in the range of 600-1500 K was con- structed on the basis of DTA principle. This apparatus has some modifications up- on Hoster's calorimeter. Its reliability was proved by measuring some systems whose enthalpies of formation or phase transformation have been given out in the published literatures. The calorimeter was used to determine the enthalpies of formation of 9 alloys (with x_Fe=0.53) of Fe-Cr-V system, which no one up to now has measured except Malinsky and Claisse who did only one of these alloys. We also used it to determine the enthalpies of the sigma-alpha phase transformation of these alloys. The data obtained in present work were compared with that of Malinsky and Claisse for the ternary system, Dench and Spencer for the binary systems, and good coincidence was found between them. The experimental results thow that on the pseudobinary system of x_Fe=0.53, the enthalpies of formation of bcc Fe-Cr-V alloys change its sign from positive on the Fe-Cr side to negative on the Fe-V side.