【Basic Knowledge 7】The n/8 Law for Single Alloys (Prize Quiz)
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This post was last edited by lzy4225925 on 2015-12-7 10:51. Please explain what the n/8 law for single-alloy systems is
Please explain what the n/8 law for single-alloy systems is It was Taman who, while studying the corrosion resistance of individual alloys, discovered a special relationship between their corrosion resistance and the composition of the solid solution: the n/8 law.
It was Taman who, while studying the corrosion resistance of individual alloys, discovered a special relationship between their corrosion resistance and the composition of the solid solution: the n/8 law.
The n/8 law for single-phase alloys: In a solid solution alloy composed of a corrosion-resistant element and a non-corrosion-resistant element in a given medium, when the content of the corrosion-resistant element is 12.5%, 25%, 37.5%, 50%… in terms of atomic fraction (the ratio of the number of atoms of the corrosion-resistant element to the total number of atoms in the alloy), that is, when it corresponds to 1/8, 2/8, 3/8, 4/8… n/8 (where n = 1, 2…, 7), the corrosion resistance of the alloy increases suddenly in a stepwise manner, and the potential of the alloy rises accordingly. This rule is known as the n/8 law of alloys.
In a solid solution alloy composed of a corrosion-resistant component and a non-corrosion-resistant component in a given medium, when the content of the corrosion-resistant component corresponds to atomic fractions of 12.5%, 25%, 37.5%, 50%......that is, 1/8, 2/8, 3/8……n/8, the corrosion resistance of the alloy increases abruptly in steps, and the potential of the alloy rises as well. Here, n is referred to as the stability step.
While studying the corrosion resistance of individual alloys, Taman discovered a special relationship between their corrosion resistance and the composition of the solid solution: the n/8 rule. In a solid solution alloy composed of a corrosion-resistant element and a non-corrosion-resistant element in a given medium, when the proportion of the corrosion-resistant element is 12.5%, 25%, 37.5%, 50%...... in terms of atomic fraction, that is, 1/8, 2/8, 3/8……n/8, the alloy’s corrosion resistance increases suddenly in steps, and its electrical potential also rises accordingly. Here, n is referred to as the stability step.
Correct answer: In a given medium, it is a solid solution alloy composed of a corrosion-resistant component and a non-corrosion-resistant component; when the content of the corrosion-resistant component is 1/8, 2/8… n/8, the corrosion resistance of the alloy increases suddenly in a stepwise manner, and the alloy potential also rises accordingly.