Microstructure Evolution of Different Forging Processes for 12%Cr Steel During Hot Deformation

doi:10.1007/s12204-015-1668-x

Abstract

Abstract: 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.

Key words: microstructure, forging process| hot deformation| grain size| numerical simulation

摘要： 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.

关键词: microstructure, forging process| hot deformation| grain size| numerical simulation

CLC Number:

TG 316.2

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.

References 12

[1]	Ennis P J, Quandakkers W J. 9-12% chromium steels: Application limits and potential for further development[C]//Parson 2000 for Advanced Materials for 21st Century Turbines and Power Plant: Proceedings of the Fifth International Charles Parsons Turbine Conference. London, UK: IOM Communications,2000: 265-275.
[2]	Maruyam K, Sawada K, Koike J. Strengthening mechanisms of creep resistant tempered martensitic steel [J]. ISIJ International, 2001, 41(6): 641-653.
[3]	Dubey J S, Chilukuru H, Chakrakravartty J K,et al. Effects of cyclic deformation on subgrain evolution and creep in 9-12% Cr-steels [J]. Materials Science and Engineering A, 2005, 406: 152-159.
[4]	Sonderegger B, Mitsche S, Cerjak H.Microstructural analysis on a creep resistant martensitic 9-12%Cr steel using the EBSD method [J]. Materials Science and Engineering A, 2008, 481-482: 466-470.
[5]	Rojas D, Garcia J, Prat O, et al. Effect of processing parameters on the evolution of dislocation density and sub-grain size of a 12%Cr heat resistant steel during creep at 650?C [J]. Materials Science and Engineering A, 2011, 528: 1372-1381.
[6]	Wang B Z, Fu W T, Lv Z Q, et al. Study on hot deformation behavior of 12%Cr ultra-super-critical rotor steel [J]. Materials Science and Engineering A, 2008,487: 108-113.
[7]	Wang Z H, Fu W T, Wang B Z, et al. Study on hot deformation characteristics of 12%Cr ultra-supercritical rotor steel using processing maps and Zener-Hollomon parameter [J]. Materials Characterization,2010, 61: 25-30.
[8]	Laasraoui A, Jonas J J. Recrystallization of austenite after deformation at high temperatures and strain rates: Analysis and modeling [J]. Metallurgical Transactions A, 1991, 22A(1): 151-160.
[9]	Laasraoui A, Jonas J J. Prediction of steel flow stresses at high temperatures and strain rates [J]. Metallurgical Transactions A, 1991, 22A(7): 1545-1558.
[10]	Sui D S, Wang W, Fu B, et al. Research on flow stress model and dynamic recrystallization model of X12CrMoWVNbN10-1-1 steel [C]//The 11th international Conference on Numerical Methods in Industrial Forming Processes. Shenyang, China: AIP Publishing LLC, 2013: 826-837.
[11]	Chen F, Cui Z S, Chen S J. Recrystallization of 30Cr2Ni4MoV ultra-super-critical rotor steel during hot deformation. Part I. Dynamic recrystallization[J]. Materials Science and Engineering A, 2011, 528:5073-5080.
[12]	Poursina M, Ebrahimi H, Parvizian J. Flow stress behavior of two stainless steels: An experimentalnumerical investigation [J]. Journal of Materials Processing Technology, 2008, 199: 287-294.

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