Intergranular damage

Zinc anodes have also experienced problems at elevated temperatures in saline mud, suffering intergranular decohesion at approximately 70°C. Later work by the same authors showed the threshold for damage to be ca. 50°C. The material is not recommended above 40°C" although special zinc based materials for temperatures exceeding 50°C have been developed ... 

As is the case with other types of corrosion testing, mass-loss determinations may fail to indicate the actual damage suffered by specimens that are attacked intergranularly or in such a manner as dezincification. In such cases, mechanical tests will be required as discussed already in the section on evaluation techniques. 

Pits are found to develop particularly in the region of grain boundaries which themselves are readily open to attack ( intergranular corrosion ). Thus, it is the Cu-depleted regions that are the major cause of the intergranular damage of Al-Cu alloys. The A1 itself remains passive for a certain time and potential, but even when... 

Corrosion General corrosion, crevice corrosion, pitting, hydrogen damage, caustic corrosion, intergranular corrosion, microbiological corrosion... 

Crevice corrosion Stress corrosion cracking Intergranular corrosion Selective leaching Erosion corrosion Flydrogen damage Dilon [12] grouped corrosion into two categories. 

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