Study of Initial β-Zr Formation in β-Quenched N36 Zirconium Alloy Using Dynamic and Metallographic Methods

Abstract

In this study, the initial temperature of the (α) to (α + β) phase transformation of β-quenched N36 zirconium alloy was determined using differential scanning calorimetry (DSC) and metallographic techniques. Diagnosis and analysis of the difference between the two techniques were also conducted. It was found that the phase transition temperature, obtained by metallographic techniques, lies in a temperature range of 710–715 °C. This value is lower than that recorded by DSC analysis. A peak separation successfully explained the dissolution of the second phase particles (SPP)s and α→β phase transformation using the DSC analysis. Compared with previous studies, the results of this study showed that β-quenched starting material is responsible for the delay of β-Zr formation during the heat treatment of the N36 zirconium alloy.

Keywords

• N36 zirconium alloy
• phase transformation
• differential scanning calorimetry DSC
• metallographic techniques