Patent ID: 6219404
Filing Date: 2001-04-17
Classification: G01N

Abstract:
A method of determining if an alloy article has any remaining working life comprising the steps of:(a) taking at least one sample from an alloy article, the alloy article comprising metal matrix material and carbide particles(b) removing substantially all metal matrix material from the at least one sample to leave the carbide particles,(c) analysing the carbide particles using x-ray diffraction, identifying the x-ray peaks of the main carbide phases from the x-ray diffraction spectra,(d) determining the ratio, or the difference, of the amount of a first carbide phase to the amount of a second carbide phase,(e) providing a database containing the ratio, or difference, of the first carbide phase to the second carbide phase as a function of temperature of heat treatment and time of heat treatment,(f) comparing the ratio, or difference, of the amount of the first carbide phase to the amount of the second carbide phase determined in step (d) with the database in step (e) to determine the temperature of heat treatment and the time of heat treatment of the sample of the alloy article,(g) comparing the temperature of heat treatment and the time of heat treatment of the sample of the alloy article determined in step (f) with a plurality of different heat treatment temperatures and associated heat treatment times corresponding to the full working life of the alloy article to determine if the alloy article has any remaining working life.