Differences between field-exposed magnesium Mg and accelerated tests

9 Differences between field-exposed magnesium (Mg) and accelerated tests 

To evaluate magnesium alloys both immersion and salt spray tests are often used. Table 7.6 shows corrosion rates obtained after different types of accelerated corrosion tests taken from the literature (52, 62, 63). The corrosion rates show a wide scatter. For some of the accelerated corrosion tests such as the immersion in NaCl solution the corrosion rates are extremely high. 

Two major factors differentiate the laboratory from the field. 

Secondly The electrolyte layer is another aspect that differentiates the laboratory from the field. To accelerate the corrosion process in the laboratory, high relative humidity or bulk electrolyte is used, often together with high amounts of NaCI. A higher relative humidity results in 

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