文章信息/Info

Title:

Mechanisms and Growth Rate Models for Stress Corrosion Cracking in High Temperature Water

作者:

呂戰(zhàn)鵬

（1. 上海大學(xué)材料科學(xué)與工程學(xué)院，上海 200072)
（2. 上海大學(xué) 省部共建高品質(zhì)特殊鋼冶金與制備國(guó)家重點(diǎn)實(shí)驗(yàn)室，上海 200444）

Author(s):

LU Zhanpeng

（1. School of Materials Science and Engineering, Shanghai University, Shanghai 200072，China）
（2. State Key Laboratory of Advanced Special Steels, Shanghai University, Shanghai 200444, China)

關(guān)鍵詞:

應(yīng)力腐蝕開裂; 核電站; 高溫水; 裂紋擴(kuò)展速率; 氧化動(dòng)力學(xué); 裂尖應(yīng)變速率

Keywords:

stress corrosion cracking;  nuclear power plant;  high temperature water;  crack growth rate;  oxidation kinetics;  crack tip strain rate

DOI:

10.7502/j.issn.1674-3962.201904012

文獻(xiàn)標(biāo)志碼:

A

摘要:

核電站結(jié)構(gòu)材料在高溫水中應(yīng)力腐蝕開裂是影響安全運(yùn)行的重要因素。總結(jié)了合金成分、載荷和環(huán)境介質(zhì)等多種因素對(duì)奧氏體合金在高溫水中應(yīng)力腐蝕開裂擴(kuò)展過程的影響規(guī)律,簡(jiǎn)要介紹了幾種應(yīng)力腐蝕開裂機(jī)理模型。分析了高溫水中的應(yīng)力腐蝕開裂基元過程，提出了載荷對(duì)合金在高溫水中界面反應(yīng)的物理加速作用和物理化學(xué)加速作用原理。發(fā)展了基于連續(xù)介質(zhì)力學(xué)裂紋尖端力學(xué)場(chǎng)與氧化動(dòng)力學(xué)相結(jié)合的裂紋擴(kuò)展速率的形變/氧化交互作用理論模型，針對(duì)模型中使用的準(zhǔn)固態(tài)氧化動(dòng)力學(xué)規(guī)律以及裂尖漸進(jìn)場(chǎng)的適用性進(jìn)行了分析，發(fā)現(xiàn)環(huán)境溫度、材料成分和水化學(xué)對(duì)氧化動(dòng)力學(xué)的影響與相應(yīng)條件下奧氏體合金應(yīng)力腐蝕開裂行為變化特征相對(duì)應(yīng)，裂尖漸進(jìn)場(chǎng)的適用性也得到了驗(yàn)證。將形變/氧化交互作用模型應(yīng)用于多種條件下不銹鋼和鎳基合金在壓水堆一回路水中應(yīng)力腐蝕開裂擴(kuò)展速率評(píng)價(jià)，所得模型預(yù)測(cè)結(jié)果與實(shí)驗(yàn)室和現(xiàn)場(chǎng)數(shù)據(jù)結(jié)果相一致。

Abstract:

Stress corrosion cracking (SCC) of structural materials in high temperature water in nuclear power plants is one of the important factors for the safety operation. In this paper, the effects of alloy composition, loading and environmental factors on SCC growth of austenitic alloys in high temperature water environments are reviewed. Some available SCC mechanisms are briefly introduced. The element processes involved in SCC are categorized, and the physical degradation and physical�瞔hemical degradation modes due to loading on the interfacial reactions in high temprature water are proposed. The deformation/oxidation interaction model for SCC growth rate is developed, based on the combination of the crack tip continuum mechanics and the oxidation kinetics. The fittness for the adopted oxidation kinetics and the crack tip asymptotic field in the SCC growth rate model is checked. It is found that the effects of temperature, material composition and water chemistry on oxidation kinetics correspond well to their effects on SCC growth rate. The compatibility of the adopted crack tip mechanical field is also confirmed. The calculated results with the developed SCC growth rate model based on deformation/oxidation interaction are found to be consistent with the reported experimental SCC growth rates and plant data.