摘要
目的研究40Cr在海水环境中的自然腐蚀行为。方法采用形貌分析、腐蚀质量损失分析、XRD分析等方法对40Cr在青岛、舟山、三亚海水全浸区的腐蚀行为进行研究。结果40Cr在不同海域中的腐蚀均较为严重,青岛及三亚海域的试样表面被大量海生物附着,舟山海域的试样表面则以泥沙沉积为主。去掉腐蚀产物后试样的腐蚀形貌以坑蚀为主。在试验周期内,随着时间的延长,试样的腐蚀速率逐渐减小,在不同周期内均以三亚海域的为最高。在相同条件下与普通碳钢(Q235)相比,40Cr的腐蚀速率偏高。随着时间的延长,青岛、舟山试样点蚀深度逐渐增加,而三亚试样点蚀深度则先增加后减小,同周期下青岛海域试样的点蚀深度最小。不同海域及周期下40Cr的腐蚀产物以稳态α-FeOOH及Fe2O3为主。结论40Cr在三个海域的腐蚀形貌均以坑蚀为主,试验周期内试样在三个海域的腐蚀速率随时间延长逐渐减小,同周期下三亚海域试样的腐蚀最为严重;40Cr中C含量较高,在相同条件下其腐蚀速率要高于普通碳钢;40Cr的腐蚀产物以稳态成分为主,是由于Cr元素含量较普通碳钢增加,加速了钢的腐蚀产物到热力学稳定状态的转化。
The paper aims to study natural corrosion behavior of 40Cr in seawater.The corrosion behavior of 40Cr steel at full-immersion zone in Qingdao,Zhoushan and Sanya sea area was studied by means of morphology,corrosion weight loss and XRD analysis.The results showed that 40Cr steel corroded seriously in different seawater.Samples were covered with huge amount of marine organism in Qingdao and Sanya sea area,and silt in Zhoushan sea area as while.Pitting was the main corro-sion morphology after removing the corrosion products.During test period,corrosion rates decreased as time prolonged,and samples in Sanya sea area corroded fastest under the same test period.In contrast with Q235 under same test condition,corro-sion rates of 40Cr were higher.Pitting depth increased as time prolonged in Qingdao and Zhoushan sea area,while increasing first then decreasing in Sanya sea area,and samples in Qingdao sea area got the most shallow pitting depth under the same test period.Corrosion products were composed ofα-FeOOH and Fe2O3,which were in steady state,regardless of test sea area or pe-riod.Pitting corrosion is the mainly corrosion morphology in the three sea areas.During test period,the corrosion rate of the samples in the three sea areas gradually decreases as time prolonged,and the corrosion of the samples in Sanya sea area is the most serious under same test condition.The content of C in 40Cr steel is higher,and its corrosion rate is higher than that of or-dinary carbon steel under the same conditions.The corrosion products of 40Cr steel are mainly steady-state components,proba-bly because of chromium addition,which catalyzed corrosion products converting to thermodynamic steady state.
作者
张彭辉
赵建仓
丁康康
程文华
ZHANG Peng-hui;ZHAO Jian-cang;DING Kang-kang;CHENG Wen-hua(State Key Laboratory for Marine Corrosion and Protection,Luoyang Ship Material Research Institute(LSMRI),Qingdao 266101,China)
出处
《装备环境工程》
CAS
2021年第11期114-120,共7页
Equipment Environmental Engineering
关键词
40CR钢
海水
腐蚀
40Cr steel
seawater
corrosion
