Influence of 1%Nb Solute Addition on the Thermal Stability of In Situ Consolidated Nanocrystalline Cu. Issue 4 (30th January 2019)

• Record Type: Journal Article
• Authors: Abaza, Mohamed A.; Al‐Sulaiti, Leena; Scattergood, Ronald O.; Youssef, Khaled M.
• Other Names: von Hehl Axel guestEditor.
• Is Part Of: Advanced engineering materials. Volume 21:Issue 4(2019)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2019-01-30
• Subjects: copper -- mechanical properties -- nanocrystalline materials -- niobium -- thermal stability; Materials -- Periodicals; 620.11
• DOI: 10.1002/adem.201800859
• Languages: English
• ISSNs: 1438-1656

Abstract

Abstract : Nanocrystalline (nc) Cu and Cu–1% Nb bulk materials are synthesized using a combination of cryogenic and room temperature ball milling. The grain size values of these in situ consolidated Cu and Cu–1% Nb, determined using transmission electron microscopy, are found to be 22 nm and 18 nm, respectively. In this investigation, isochronal heat treatments are performed for 1 h to establish grain size and microstructural changes as a function of temperature. The annealing of nc Cu–1% Nb at a temperature of 1073 K reveals a slight increase in the average grain size from 18 to 45 nm. The grain size of nc Cu, however, increases from 22 nm to about 3 μm after annealing at the same conditions. The present results indicate that solute entrapment plays a major role in thermal stability of the high purity contaminant‐free Cu with the addition of only 1 at% Nb after annealing for 1 h up to a homologous temperature of 0.8. Kinetic stabilization via clustering of Nb atoms on the grain boundaries and the triple junctions is also observed after annealing at high temperature for longer times. Abstract : The article reports extraordinary thermal stability of the high purity contaminant‐free Cu with the addition of only 1 at% Nb. Solute entrapment and clustering of Nb atoms on the grain boundaries and the triple junctions of Cu play a major role in thermal stability after annealing up to a homologous temperature of 0.8.