Accession Number : AD0016713

Title :   CORRELATIONS OF RUPTURE DATA FOR METALS AT ELEVATED TEMPERATURES

Corporate Author : MATERIALS RESEARCH LAB UNIV OF CALIF BERKELEY

Personal Author(s) : ORR,RAYMOND L. ; SHERBY,OLEG D. ; DORN,JOHN E.

Report Date : 01 JUL 1953

Pagination or Media Count : 1

Abstract : The general validity of the concepts leading to the equation f(sigma) = t sub r e-Delta H sub r/RT was tested by applying the equation to available high-temperature stress-rupture data for relatively pure metals and dilute alloys. The equation relates the time to rupture t sub r at high temperatures to the test temperature T (Kelvin) and applied stress sigma; R is the gas constant and Delta H sub r is the activation energy for rupture. The equation was successfully applied to data for Al, Be, Ti, Ni, Nb, and Mo. The formula was also applied successfully to rupture data for 24 complex high-strength commercial alloys. The activation energy Delta H sub r appeared to be constant for a given metal; for relatively pure metals it is believed to be equal to the activation energy for creep or self-diffusion.

Descriptors :   ACTIVATION ENERGY, ALLOYS, CREEP, DILUTION, EQUATIONS, GASES, HIGH TEMPERATURE, METALS, PURITY, RUPTURE, STRESSES, TEMPERATURE, TEST AND EVALUATION, TIME, VALIDATION.

Distribution Statement : APPROVED FOR PUBLIC RELEASE