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definitions

foamed metal

or foam metal

noun Chemistry, Metallurgy.
  1. a uniform foamlike metal structure produced when hydrogen bubbles are evolved from metal hydrides uniformly dispersed throughout a host metal or metal alloy: used as a structural material because of its shock-absorbing properties and light weight.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018