Accession Number : AD0672340

Title :   AN INVESTIGATION OF THE PHYSIOCHEMICAL NATURE OF METAL-LIKE AND NONMETALLIC HIGH-MELTING COMPOUNDS BY THE MICROHARDNESS METHOD (ISSLEDOVANIE FIZIKOKHIMICHESKOI PRIRODY METALLOPODOVNYKH I NEMETALLICHESKIKH TUGOPLAVKIKH SOEDINENII METODOM MIKROTVERDOSTI),

Corporate Author : FOREIGN TECHNOLOGY DIV WRIGHT-PATTERSON AFB OHIO

Personal Author(s) : Samsonov,G. V.

Report Date : 12 SEP 1967

Pagination or Media Count : 24

Abstract : This review of microhardness is concerned with metalloid and nonmetallic refractory compounds. The author attempts to show that microhardness depends mainly on two factors: electron density and crystal structure. The microhardness of a number of transition metals, carbides, nitrides, borides, and silicides is compared in terms of the electron-accepting ability of the d-orbitals = 1/Nn, where n is the number of electrons in the incompleted d-orbital and N the principal quantum number of the d-orbital. It is noted that microhardness increases with increase in (1/Nn) and with the degree of symmetry of the electron distribution. For nonmetallic compounds, the microhardness depends on the nature of the p-function and decreases with increase in the principal quantum number of the p-electrons.

Descriptors :   (*REFRACTORY MATERIALS, HARDNESS), NITRIDES, CARBIDES, SILICIDES, BORIDES, ATOMIC ORBITALS, ELECTRON DENSITY, CRYSTAL STRUCTURE, USSR

Subject Categories : Ceramics, Refractories and Glass
      Atomic and Molecular Physics and Spectroscopy

Distribution Statement : APPROVED FOR PUBLIC RELEASE