周军,邱绍宇,邱日盛,曾文,王浩,肖婷,卓洪

• 1:中国核动力研究设计院核燃料元件及材料研究所
• 2:重庆大学材料科学与工程学院

摘要(Abstract)：

铁素体马氏体(F/M)钢是铅冷快堆堆芯的主要候选材料之一，提高F/M钢中的Si含量可提高其抗腐蚀性能，但会促进Laves相的析出从而影响其塑韧性。针对5种Si含量(0.34～1.20 mass%)的9%Cr F/M钢，开展了600℃下热老化不同时间的试验，研究了Si含量对其Laves相析出行为和冲击性能的影响。结果表明：热老化250 h后，5种Si含量的F/M钢均在原奥氏体晶界和马氏体板条界面上析出了不规则颗粒状为主的Laves相；随着热老化时间的增加，Laves相面积分数先增加后保持稳定，而平均直径逐渐增加。相同的热老化时间下，Laves相的密度和面积分数随Si含量的增加逐渐增加，但随着Si含量的增加，Si含量的影响呈现逐步减弱的趋势，当Si含量达到0.98 mass%后，进一步增加Si含量不会显著影响Laves相的析出行为。Si含量对Laves相的平均直径、粗化速度和化学成分的影响不显著，Laves相在600℃下的粗化速度约为8.5 nm/h~(1/3)。热老化250 h后，不同Si含量的F/M钢冲击性能均显著退化；相同热老化时间下，F/M钢的冲击性能随Si含量的增加有下降的趋势，Laves相的析出是冲击性能退化的主要原因。

关键词(KeyWords)： 9%Cr铁素体马氏体钢;Si含量;Laves相;冲击性能

Abstract:

Keywords:

基金项目(Foundation): 中核集团集中研发项目“铅铋合金冷却反应堆技术”

作者(Author): 周军,邱绍宇,邱日盛,曾文,王浩,肖婷,卓洪

DOI: 10.13289/j.issn.1009-6264.2021-0527

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