工程科学学报 (Oct 2015)

Hot deformation behavior and processing maps of Cr20Ni80 electrothermal alloy

  • LI Ya-min,
  • GONG Nai-guo

DOI
https://doi.org/10.13374/j.issn2095-9389.2015.10.013
Journal volume & issue
Vol. 37, no. 10
pp. 1338 – 1343

Abstract

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To solve the problem of forging cracks,the hot deformation behavior of Cr20Ni80 electrothermal alloy was investigated by compression tests on a Gleeble-1500 D thermal simulation machine in a temperature range of 900 to 1220℃ and a strain rate of 0.001 to 10 s-1. The hot processing map of the alloy was established according to the dynamic materials model(DMM). It is found that the true stress-true strain curves have steady-state flow characteristics. The peak stress increases with decreasing deformation temperature or increasing strain rate. The flow behavior is described by a hyperbolic sine constitutive equation,and the activation energy of the alloy is about 371.29 kJ·mol-1. Based on the processing map,the process of hot deformation in the temperature range at different strain rates can be attained,of which the optimum hot deformation temperature ranges in 1050-1200℃ and the strain rate is 0.03-0.08 s-1,and the instability zones of flow behavior can also be recognized. The optimal hot-working technology is validated to be successful in production.

Keywords