压水堆用690合金传热管模拟服役环境中微动图的建立、磨损机制与损伤机理研究

微动磨损是压水堆核电站中690合金传热管长期服役过程中最主要的失效形式，至今未解决的根本原因是模拟真实高温高压极端服役环境中的研究难度大、数据少。根据国内外研究调研，提出了模拟真实环境、两类微动图的建立和微动损伤微纳尺度表征3个亟需解决的问题并制定了研究方案。申请人拟利用团队研制的高温高压微动磨损测试系统，在模拟690传热管高温高压二回路水/水蒸汽服役环境中对其微动磨损行为进行系统研究：通过实验设计，快速建立690传热管的运行工况微动图；在不同的微动区域、微动区域边界上选取典型法向载荷和位移幅值进行长期微动磨损实验，通过对微动损伤的宏观、微观分析，建立材料响应微动图，弄清690合金传热管在不同微动区域下的微动磨损机制及损伤机理，并形成微动损伤模型和寿命预测模型。研究将为蒸汽发生器的结构设计、振动控制和寿命评估提供准确的数据支撑和理论支持，对我国核电站的安全可靠运行和延寿具有重要意义。

Fretting wear has become the main failure mode of Alloy 690 heat exchanger tubes in pressurized water reactor nuclear power plant during the long-term operation, and the fundamental reason for why it has not been solved so far is that it is difficult to simulate the real service environment during fretting wear test and the data is limited. According to the domestic and international research status, three urgent problems, real service environment experiment, establishment of two types of fretting maps and micro-nano scale characterization of fretting damage, are put forward and a corresponding research plan is made. The applicant intends to use the high temperature high pressure fretting wear testing system developed by our own team to systematically study the fretting wear behavior of 690 heat exchanger tubes in the simulated real service environment (high temperature high pressure secondary loop water/steam). By a well-designed method, the running condition fretting map will be quickly established. Then, typical combinations of normal force and displacement amplitude are selected to carry out fretting wear tests in different fretting regimes and regime boundaries. The material response fretting map will be established through macro and micro analysis of fretting damages. Finally, the fretting wear and damage mechanism of Alloy 690 heat exchanger tube in simulated high temperature high pressure service environment will be investigated, and the fretting damage model and life prediction mode will be established. The research will provide accurate data support for the structural design, vibration control and life evaluation of steam generators, which has important engineering significance for the safe and reliable operation and life extension of nuclear power plants in China.