ASTM G100-89(2015)
循环电流梯级极化的标准试验方法

Standard Test Method for Conducting Cyclic Galvanostaircase Polarization

被代替

标准号

ASTM G100-89(2015)

发布

1989年

发布单位

美国材料与试验协会

替代标准

ASTM G100-89(2021)

当前最新

ASTM G100-89(2021)

 

 

引用标准

ASTM D1193 ASTM G1 ASTM G5 ASTM G59 ASTM G69

适用范围

3.1 In this test method, susceptibility to localized corrosion of aluminum is indicated by a protection potential (E_prot) determined by cyclic galvanostaircase polarization (1). The more noble this potential, the less susceptible is the alloy to initiation of localized corrosion. The results of this test method are not intended to correlate in a quantitative manner with the rate of propagation of localized corrosion that one might observe in service.

3.2 The breakdown (E_b), and protection potentials (E_prot) determined by the cyclic GSCP method correlate with the constant potential corrosion test (immersion-glassware) result for aluminum (1, 6, 7). When the applied potential was more negative than the GSCP E_prot, no pit initiation was observed. When the applied potential was more positive than the GSCP E_prot, pitting occurred even when the applied potential was less negative than E_b.

3.2.1 Severe crevice corrosion occurred when the separation of E_b and E_prot was 500 mV or greater and E_prot was less than8201;−400 mV Vs. SCE (in 100 ppm NaCl) (1, 6, 8). For aluminum, E_prot determined by cyclic GSCP agrees with the repassivation potential determined by the scratch potentiostatic method (1, 9). Both the scratch potentiostatic method and the constant potential technique for determination of E_prot require much longer test times and ar......

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