| Title |
Control of Grain Size and Precipitation by Dynamic Recrystallization Controlled Deformation for Fe - 36Ni Alloy |
| Authors |
권용환(Yong Hwan Kwon); 이성노(Sung Noh Lee); 조상현(Sang Hyun Cho); 유연철(Yeon Chul Yoo) |
| Abstract |
Dynamic recrystallization controlled rolling(DRCR) process was simulated by multistage torsion tests to understand the variation of the grain size and the precipitation of Invar alloy in the range of 800∼1100℃ and 4.0×10^(-2)∼2.6×10^0/sec. The critical strain(ε_c) for the initiation of dynamic recrystallization(DRX) was determined by plotting the strain hardening rate(θ) as a function of stress(σ). The relationship between ε_c and ε_p was found to be ε_c ≒ 0.67∼0.78ε_p. As increasing strain, the grain size decreased and the number and size of precipitates increased. Grain refinement was accelerated by the penultimate pass in the DRCR while the area fraction of precipitation could be reduced by the alternative large pass strain at the earlier pass under the condition of high temperature and low strain rate. Also the correlation between the grain size and the precipitate size was discussed in relation to the deformation processing variables. |