Zhengfu WANG
,
Jin LI
,
Jianqiu WANG and Wei KE(Corrosion Science Laboratory
,
Institute of Corrosion and Protection of Metals
,
Chinese Academy of Sciences
,
Shenyang
,
110015
,
China)
材料科学技术(英文)
The paper reports the effect of0.01,0.1 and 1%NaNO2, a passive inhibitor, on corrosion fatigue (CF) crack initiation and propagation for a low strength structural steel A537 in 3.5%NaCl aqueous solution. The experimental results show that inhibitor increases the required cycles of CF crack initiation effectively, and this effect increases with increasing inhibitor concentration.However, there is nearly no effect of NaNO2 on CF crack propagation. The same CF crack propagation rate was found in all kinds of solutions. The results also indicate that the passive time in 1%NaNO2 solution during plastic deformation is much longer than cyclic time. NaNO2 passivates the specimen sudece and repairs passive film damaged by cyclic loading during the crack initiation. while the passsive film is not formed fully due to continuous plastic deformation at the crack tip during the CF crack propagation, which is much different from that in the stress corrosion cracking and general corrosion
关键词:
Zhengfu WANG
,
Xuejun WEI
,
Jin LI and Wei KE(State Key Lab. for Corrosion and Protection
,
Institute of Corrosion and Protection of Metals
,
Chinese Academy of Sciences
,
Shenyang 110015
,
China)
材料科学技术(英文)
The transient current behaviour for Iron in 3.5%NaCl and 3.5%NaCl +1%NaNO2 solutions during corrosion fatigue (CF) process has been investigated at different given strain amplitudes and strain rates. The results show that elastic strain has little contribution to material dissolution. The elastic tension strain results in the decrease in the transient current, while the elastic compression strain increases the transient current. Compared to the elastic deformation, plastic deformation affects material dissolution evidently For iron in 3.5%NaCl solution, the strain amplitude plays a dominant role in the dissolution process accelerated by the plastic strain, while in 3.5%NaCl+1%NaNO2 solution, both the strain amplitude and strain rate play an important role in this process. In this paper, the effect of the elastic deformation on the material dissolution and the relation between the tension and compression current peak values under the plastic cycle deformation are discussed
关键词: