铜铬镧合金中第二相铬颗粒定量金相分析

比较了电解浸蚀法和化学浸蚀法对Cu0．8wt％Cr0．4wt％La合金金相组织的显示效果及其对定量金相分析的影响。采用蒸馏水(333mL)、磷酸(166mL)、酒精(166mL)、尿素(2g)和异丙醇(33mL)的混合溶液作为电解液，在电流密度为1A／cm^2，浸蚀时间为20sec的条件下浸蚀试样。对试样在时效过程中第二相的几何特征参数变化进行了定量金相分析。结果表明：电解浸蚀法可以有效消除试样磨制过程中的划痕，更加突出地显示合金中铬相的金相形貌，提高定量金相分析的效率和准确度。

QUANTITATIVE METALLOGRAPHIC ANALYSIS OF Cr PHASE IN CuCrLa ALLOY

The electro-etching and chemical etching methods have been used to reveal microstructures of Cu-0.8 wt%Cr-0.4wt%La samples for quantitative metallographic analysis to acquire a optimal etching technique. Samples are determinately etched in a solution of distilled water (333 mL), phosphoric acid (166 mL), alcohol (166 mL), carbamide(2 g) and isopropanol(33 mL) for 20sec under current density of 1A/cm~2. And characteristic geometric parameters of precipitated Cr particles during aging have been measured by using quantitative metallographic method.The results show that electro-etching method may not only effectively avoid the scratch appearance during the sample grind, but also more clearly reveal microstructure and improve the efficiency and accuracy of quantitative metallographic analysis.