The experimental determination of the melting heat for E635 zirconium alloy

A procedure is developed for the determination of the melting heat of zirconium alloys which is based on the preparation of an ampoule in the form of a thin oxide film on the surface of a specimen during its rapid heating in air. Owing to its higher melting point, the zirconium oxide film "holds" the specimen at temperatures exceeding the melting point. The brightness (for the wavelength of $0.65$ мm) solidus and liquidus temperatures of E635 zirconium alloy are measured, and the respective true temperatures are calculated using the measured values of spectral emissivity. The data obtained on the melting heat and the heat of $\alpha$–$\beta$-transition are presented.