Interstitial alloys and related compounds

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Next consider the relative sizes of the atoms. The structure of many metals is a close-packed lattice of spherical atoms or ions. There are therefore many tetrahedral and octahedral holes. If the element added has small atoms, they can be accommodated in these holes without altering the structure of the tnetal. Hydrogen is small enough to occupy tetrahedral holes, but most other elements occupy the larger octahedral holes. The invading atoms occupy interstitial.positions in the metal lattice, instead of replacing the metal atoms. The chemical composition of compounds Of this type may. vary over a wide range depending on how many holes are occupied. Such alloys are called interstitial solid solutions, and are formed by a: wide range of metals with hydrogen, boron, carbon, nitrogen and other eletrients'. The most li'tlportant factor is the size of the invading atoms. 












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