| Title |
Grain Refinement and Mechanical Properties Improvement in a Severely Plastic Deformed Ni-30Cr Alloy |
| Authors |
송국현(Kuk Hyun Song); 김한솔(Han Sol Kim); 김원용(Won Yong Kim) |
| DOI |
https://doi.org/10.3365/KJMM.2011.49.8.649 |
| ISSN |
1738-8228(ISSN), 2288-8241(eISSN) |
| Keywords |
metals; cold working; grain refinement; electron backscattering diffraction; EBSD; mechanical properties |
| Abstract |
The present study evaluated the microstructures and mechanical properties of severely deformed Ni-30Cr alloys. Cross-roll rolling (CRR) process was introduced as a severe plastic deformation (SPD), and Ni-30Cr alloy sheets were cold rolled to 90% thickness reduction and subsequently annealed at 700℃ for 30 min to obtain the recrystallized microstructure. Electron back-scattering diffraction (EBSD) was introduced to analyze grain boundary character distributions (GBCDs). The application of CRR to the Ni-30Cr alloy was effective in enhancing the grain refinement through heat treatment; consequently, the average grain size was significantly refined from 33㎛in the initial material to 0.6㎛. This grain refinement directly improved the mechanical properties, in which yield and tensile strengths significantly increased relative to those of the initial material. We systematically discuss the grain refinement and accompanying improvement of the mechanical properties, in terms of the effective strain imposed by CRR relative to conventional rolling (CR). |