Accession Number : AD0696954

Title :   EFFECTS OF GROWTH MECHANISM ON SOLUTION KINETICS.

Descriptive Note : Technical rept.,

Corporate Author : DREXEL INST OF TECH PHILADELPHIA PA DEPT OF METALLURGICAL ENGINEERING

Personal Author(s) : Tanzilli,Richard A. ; Heckel,Richard W.

Report Date : OCT 1969

Pagination or Media Count : 21

Abstract : The solution kinetics of second phases were studied as a function of various initial conditions resulting from either diffusion-controlled growth or interface-reaction-controlled growth prior to solution treatment. Calculations of solution kinetics based upon a planar, finite-geometry model were carried out using numerical methods and computer techniques. It was shown that second-phase particles formed by diffusion-controlled growth and existing in a matrix containing concentration gradients exhibit dissolution kinetics that differ markedly from those of particles formed by interface-reaction-controlled growth. An experimental analysis designed to use solution kinetics measurements to obtain the mechanism of growth of second phases is discussed. The effects of linear-gradient assumptions that have been used in an existing, closed-form, infinite-geometry model are evaluated. (Author)

Descriptors :   (*CRYSTAL GROWTH, *PHASE STUDIES), (*PARTICLE SIZE, PHASE STUDIES), (*ALLOYS, PHASE STUDIES), KINETIC THEORY, SOLUTIONS(MIXTURES), MATHEMATICAL ANALYSIS

Subject Categories : Properties of Metals and Alloys

Distribution Statement : APPROVED FOR PUBLIC RELEASE