Accession Number : AD0713595

Title :   ENVIRONMENT-SENSITIVE MACHINING BEHAVIOR OF NONMETALS.

Descriptive Note : Technical rept. no. 2,

Corporate Author : MARTIN MARIETTA CORP BALTIMORE MD RESEARCH INST FOR ADVANCED STUDIES

Personal Author(s) : Westwood,A. R. C. ; Latanision,R. M.

Report Date : OCT 1970

Pagination or Media Count : 56

Abstract : Liquid environments can influence the efficiency of machining nonmetallic solids in a variety of ways, e.g., by serving as lubricants, coolants, or particle dispersants. Because of its technological potential, the characteristics and possible mechanisms of this latter phenomenon -- the Rebinder effect -- receive primary consideration in this paper. For crystalline ceramics, Rebinder effects in machining arise because of the influence of the environment on near-surface dislocation behavior. Effects resulting from adsorption-induced changes in the surface free energy of the solid are of minor importance. Rebinder effects can also occur in non-crystalline solids, however, and recent observations on such effects in various glasses are described. The possibility that these effects are caused by a stress-plus-chemisorption-induced redistribution of sodium ions in the near-surface region is discussed. The importance of considering the total cutting system, environment - solid - tool, in any account of environment-sensitive machining is stressed, for environments which facilitate material removal when one type of tool is used can be detrimental to the effectiveness of another tool with a different cutting action. (Author)

Descriptors :   (*GLASS, *DRILLING), (*CERAMIC MATERIALS, *MACHINING), (*CUTTING FLUIDS, CERAMIC MATERIALS), ADSORPTION, SURFACE PROPERTIES, IMPURITIES, CRACKS, MECHANICAL PROPERTIES, MAGNESIUM OXIDES

Subject Categories : Ceramics, Refractories and Glass

Distribution Statement : APPROVED FOR PUBLIC RELEASE