Abstract
The thermal deformation microstructure of continuous extrusion copper bus bar was observed and analyzed in the temperature range from 200°C to 700°C and at strain rate from 0.01s-1 to 10.0s-1 and at deformation amount from30% to 90% on Gleeble1500 test machine. The experiment results show that the higher the temperature, the lower the strain rate, the more dynamic recrystallization occurred. At the same strain rate, the copper bus bar changes from raw material of as-cast organization to recrystallization grain gradually as the deformation temperature and deformation degree increase, and the recrystallization grain size grows older with the rise of temperature. At the same deformation temperature, the temperature of recrystallization nucleation decreases while the strain rate increases. At low strain rate (0.01~1.0s-1), the dynamic recrystallization occurred at 500°C. While at high strain rate (10.0s-1), the recrystallization nucleation is advanced and it is already completed at 500°C. The Z parameters can be used to express the effect of deformation temperature and strain rate on the average grain size D, and the prediction model of the thermal deformation microstructure is obtained as follows: lnD=4.822-0.018lnZ
Highlights
Because of good corrosion resistance and large carrying capacity, copper bus bar are often used in power transmission or transformation equipments in hydropower plants, nuclear power plants, subways, airports, high-speed trains and so on
The deformation is set to 50%, while the deformation temperature varies from 200°C to 700°C and the strain rate varies from 0.01s-1 to 10.0-1
The deformation temperature ranges from 200°C to 700°C and the strain rate varies from 0.01s-1 to 10.0s-1
Summary
The updraft continuous casting pure copper rod, the raw material for copper bus bas production, is compressed at rising temperature and constant temperature respectively by Gleeble1500 thermal simulation test machine [12]. The deformation is set to 50%, while the deformation temperature varies from 200°C to 700°C and the strain rate varies from 0.01s-1 to 10.0-1. The deformation temperature stays at 600°C and the strain rate is, the final deformation amount are 30%, 70% and 90%. Samples are quenched into the water immediately after being compressed at high temperature to make the deformed microstructure fixed and unchangeable. To prepare the metallographic samples, thermal deformed specimens are cut along the longitudinal section, paralleling to the compression direction by the wire cutting machine firstly. The thermal deformations of microstructures are observed and photographed in polarized state by large XJG-05 metallographic microscope xenon lamp. The average grain size is calculated by the wire cutting method. 20 fields are observed to calculate the average grain size
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
