metal clad

Cladding is the bonding together of dissimilar metals. It is different from fusion welding or gluing as a method to fasten the metals together. Cladding is often achieved by extruding two metals through a die as well as pressing or rolling sheets together under high pressure.
The United States Mint uses cladding to manufacture coins from different metals. This allows a cheaper metal to be used as a filler. For example, dimes and quarters struck since 1965 have cores made from pure copper, with a clad layer consisting of 75% copper and 25% nickel added during production. Half dollars struck from 1965 to 1969 for circulation and in 1970 for collectors also incorporated cladding, albeit in the case of those coins, the core was a mixture of 20.9% silver and 79.1% copper, and its clad layer was 80% silver and 20% copper. Half dollars struck since 1971 are produced identically to the dimes and quarters.
Laser cladding is an additive manufacturing approach for metal coatings or precise piece restorations by using high power multi-mode optical fiber laser.

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