Year: 2025
Type: article
Abstract: This study examines the phase transitions occurring during linear heating of the Zr15Nb alloy through a comprehensive, multi-technique methodology comprising in situ high-energy synchrotron X-ray diffraction (HEXRD), electrical resistance measurements, differential scanning calorimetry (DSC) and thermal expansion analysis, supplemented by ex situ transmission electron microscopy (TEM). The findings reveal a complex sequence of phase transformations and corresponding structural changes over a broad temperature range (from room temperature up to 800 °C). Two distinct body-centered cubic (bcc) β phases β Zr and β Nb with closely related lattice parameters are identified. At room temperature, the microstructure is characterized by a mixture of the metastable β Zr + ω ath phase. Upon heating, β Zr progressively decomposes, giving rise to the formation of β Nb . TEM observation revealed the cuboidal shape of the ω iso particles, resulting from the high lattice misfit between β and ω phase. The ω solvus temperature is determined to be approximately 555 °C, as evidenced by in situ HEXRD and abrupt changes in the alloy’s thermal and electrical properties. The growth of the α phase occurs after the dissolution of the ω phase, resulting in a pronounced increase in thermal expansion. Graphical Abstract
Source: Journal of Materials Science
Institutions: Charles University, Universitat Politècnica de Catalunya
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $3,590
Funders: Univerzita Karlova v Praze, Grantová Agentura, Univerzita Karlova, European Commission, Ministerstvo Školství, Mládeže a Tělovýchovy, Grantová Agentura České Republiky, Ministerio de Ciencia e Innovación, Materials Growth and Measurement Laboratory, Deutsches Elektronen-Synchrotron, Agència de Gestió d'Ajuts Universitaris i de Recerca, Research Fund for Coal and Steel
OpenAlex ID: W4417042486