Five forging experiments were designed and conducted to investigate the effect of process parameters
on microstructure evolution during hot deformation for X12CrMoWVNbN10-1-1 steel. The experimental results
indicated that average grain size became finer with the increasing number of upsetting and stretching. Especially,
the size of stretching three times with upsetting twice had the most remarkable effect on refinement, and the size
was only 27.36% of the original one. Moreover, the stress model was integrated into the software and finite element
models were established. Simulation results demonstrated that the strain at center point of workpiece was far larger
than critical strain value in each process, so that dynamic recrystallization (DRX) occurred in each workpiece,
which implied DRX could occur for several times with the increasing number of upsetting and stretching, and
uniform finer microstructure would be obtained. However, the results also showed that higher temperature was
an unfavorable factor for grain refinement, so the times of heating should be limited for workpiece, and as many
forging processes as possible should be finished in once heating.
SUI Da-shan*(隋大山), GAO Liang (高 亮), CUI Zhen-shan (崔振山)
. Microstructure Evolution of Different Forging Processes for 12%Cr Steel During Hot Deformation[J]. Journal of Shanghai Jiaotong University(Science), 2015
, 20(5)
: 606
-611
.
DOI: 10.1007/s12204-015-1668-x
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