Accession Number : AD0626602

Title :   HARMONIC ANALYSIS METHOD FOR THE NONDESTRUCTIVE DETERMINATION OF CASE DEPTH OF CARBURIZED STEEL.

Descriptive Note : Technical rept.,

Corporate Author : SPRINGFIELD ARMORY MASS

Personal Author(s) : Fowler,K. A. ; Hatch,H. P.

Report Date : 30 NOV 1965

Pagination or Media Count : 36

Abstract : An investigation concerned with the nondestructive determination of case depth by harmonic voltage analysis measurements was continued. A prototype test instrument was designed and constructed which permits rapid, accurate measurement of the amplitude, phase, and inphase and quadrature components of harmonic frequencies generated by the test piece under the influence of sinusoidal applied field. The design of the instrument is such that a wide range of frequency and strength of applied field can be investigated. It has been established by comparative measurements on homogeneous plain carbon steels that the results obtained by harmonic analysis are primarily produced by the additional surface carbon content achieved by the carburizing process rather than such secondary factors as residual stress or retained austenite. The ability to measure several voltage parameters has also been shown to be of value in effectively separating two simultaneously changing variables, i.e., case depth and tempering temperature. (Author)

Descriptors :   (*NONDESTRUCTIVE TESTING, STEEL), (*HARMONIC GENERATORS, NONDESTRUCTIVE TESTING), (*STEEL, NONDESTRUCTIVE TESTING), CASE HARDENING, THICKNESS, DETERMINATION, MAGNETIC PROPERTIES

Subject Categories : Fabrication Metallurgy
      Test Facilities, Equipment and Methods

Distribution Statement : APPROVED FOR PUBLIC RELEASE