金相法测定锆锡和锆铌系锆合金的相变温度

Determination of Phase Transformation Temperatures of Zr-Sn and Zr-Nb Zircaloys by Metallographic Method

采用金相法测定了锆锡系Zr4锆合金和锆铌系N36锆合金由α+β相转变为β相的相变温度T_(α+β→β)。结果表明:可以通过金相法测定锆合金的相变温度T_(α+β→β),在相变温度T_(α+β→β)附近淬火,通过观察试样α相含量的变化,确定α相未完全转变和完全转变的温度区间,相变温度T_(α+β→β)取该区间的下限值,热处理加热温度间隔建议选择为10℃;试验测得Zr4锆合金的T_(α+β→β)为970℃,N36锆合金的T_(α+β→β)为890℃。

The phase transformation temperature T_（α＋β→β）from α ＋ βphase toβphase of Zr-4 and N36 zircaloys was determined by metallographic method.The results show that the phase transformation temperature T_（α＋β→β）of zircaloys could be determined by metallographic method.By quenching the samples at the temperatures near the phase transformation temperature T_（α＋β→β）and then observing the change ofα phase contents,the temperature range of incomplete transformation and complete transformation ofαphase was determined,and the lower limit value of the temperature range was taken as the phase transformation temperature T_（α＋β→β）.The recommended heat treatment heating temperature interval was 10 ℃.The measured T_（α＋β→β）of Zr-4 zircaloy was970 ℃,and the T_（α＋β→β）of N36 zircaloy was 890 ℃.