Thermal stability of functional properties in dispersion and precipitation hardened selected copper alloys

摘要

Purpose: The objective of the study was to produce copper-based dispersion hardened materials of submicron grain size, determination of their basic functional properties and stability in high temperature, as well as comparison of those properties with properties of selected precipitation hardened copper alloys made by classical method of melting, casting and thermomechanical processing.Design/methodology/approach: The examination was conducted on copper hardened with WC, Y2O3and Cr3Si particles and on precipitation hardened copper alloys with addition of Cr and Ni, Si, Cr. The examination of the materials covered changes in hardness, electrical conductivity and stabilities of those properties after various heat treatment options.Findings: Assuming the tendency to softening depending on annealing temperature to be as a criterion of properties stability, temperature ranges of individual alloys applications were determinedResearch limitations/implications: The study could be supplemented with information on tendencies to high-temperature creep in the examined alloysPractical implications: The materials are used for components operating in high-temperature conditions, such as components of crystallizers for continuous casting of metals, electrodes for welding, in nu clear reactors, etc.Originality/value: The originality lies in examination of dispersion hardened materials (especially Cu – Cr3Si) of controlled submicrometric structure obtained from initial nanocrystalline structure