The morphology of fine metal crystallites

Abstract

Clear-cut habits were found for fine metal crystallites formed by evaporation of a metal in an atmosphere of inactive gases; helium, argon and xenon. A systematic investigation by electron microscopy on twenty-two kinds of metal for various formation conditions was carried out. Some of the distinct morphologies found so for are as follows: (1) Cubes for α-Cr, (2) octahedra for fcc metals, (3) rhombic dodecahedra for α-Fe, β-Mn and Be, (4) tristetrahedra for α-Mn, (5) icosatetrahedra for δ-Cr, (6) hexagonal plates and polyhedra for Be, Mg and Zn, (7) hexagonal rods with split ends for Te, (8) truncated triangular biprisms fcc metals, (9) pentagonal decahedra and/or icosahedra for fcc metals and γ-Fe. Nos. 1 to 7 are single crystals, No. 8 are twinned and No. 9 are so-called multiply-twinned particles. Among the single crystals, the octahedra and rhombic dodecahedra, which are more or less truncated in many cases, are possibly Wulff polyhedra for fcc and bcc crystals, respectively. © 1974.