What is the approximate thickness percentage of the Alclad layer on an aluminum sheet?

The correct answer reflects the typical thickness percentage of the Alclad layer on an aluminum sheet, which is generally in the range of 1.5% to 5%. Alclad is a cladding process used to provide a thin layer of pure aluminum over an alloy substrate. This cladding adds resistance to corrosion while maintaining the desirable mechanical properties of the aluminum alloy beneath.

The Alclad layer is deliberately kept thin to ensure that the beneficial properties of the underlying alloy, including its strength and other mechanical characteristics, are not significantly affected. The percentage reflects the fact that the bulk properties of the aluminum are derived primarily from the alloy, while the cladding serves as a protective barrier without significantly altering the characteristics of the section.

Higher percentages, like those in the other choices, would suggest a thicker layer, which is not practical for the intended application of Alclad materials in aerospace. Such thickness would hinder the structural integrity and weight efficiency that aluminum alloys offer and is beyond the conventional practice in manufacturing Alclad products.