热变形制度对09CuPTiRE钢热变形组织行为的影响

通过热模拟试验和金相组织观察，具体研究了变形温度、平均应变速率和道次间隔时间对09CuPTiRE钢的热变形组织行为及其常温组织状态的影响。结果表明：变形温度的影响最大，动态再结晶的发生程度随其降低而减小；平均应变速率和道次间隔时间的影响相对较小，随着平均应变速率增加，动态再结晶的发生程度减小，静态再结晶的软化效果减弱；随着道次间隔时间延长，静态再结晶发生更加充分。     

高导电性电极扁钢的再结晶规律

为了研究电极扁钢在高温变形时的静态再结晶软化行为,在Gleeble-1500热模拟试验机上对电极扁钢进行双道次热压缩试验,得到了该电极扁钢在不同工艺参数条件下的应力-应变曲线,研究了变形温度和道次间隔时间对电极扁钢静态再结晶行为的影响。根据试验数据结果,计算得到了电极扁钢的静态再结晶激活能,确立了静态再结晶动力学模型。结果表明:道次间隔时间和变形温度对电极扁钢静态再结晶行为的影响比较大,随着变形温度的升高和道次间隔时间的增加,电极扁钢的静态再结晶软化率也增加。     

30CrMo钢60 mm连铸板坯双道次压缩的奥氏体静态再结晶

在Thermecmastor-Z热模拟机上利用双道次压缩方法实验研究30CrMo钢60 mm连铸板坯高温变形道次间隔时间内的静态再结晶行为,分析温度（1000~1150℃）,变形量（0.1~0.22）,变形速率(0.1~10 s^-1)以及道次间隔时间（1~80 s）对其静态再结晶的影响。结果表明,温度、变形量、变形速率及道次间隔时间的增加都会促进30CrMo钢的静态再结晶;30CrMo钢的静态再结晶激活能为184.45 kJ/mol;根据实验数据建立了静态再结晶动力学模型,模型预测结果与实验结果吻合较好。     

V-N微合金钢Q550D静态再结晶行为

使用MMS-200热模拟实验机研究V-N微合金钢Q550D的静态再结晶行为,获得了其真应力-真应变曲线,同时分析了不同工艺参数对其静态再结晶过程的影响.结果表明：随着变形温度、道次间隔时间、应变量和应变速率的增加,实验钢静态软化率升高.根据实验结果计算得到该钢的静态再结晶激活能为389.4 kJ/mol,回归了静态再结晶动力学模型.     

23Co13Ni11Cr3Mo钢的奥氏体静态再结晶行为

利用GleebIe-1500热模拟实验机研究23Co13Ni11Cr3Mo超高强钢高温变形道次间隔时间内的静态软化行为,讨论变形温度、应变速率、变形程度、间隔时间及初始奥氏体晶粒尺寸等对其静态再结晶行为的影响。结果表明:变形程度对23Co13Ni11Cr3Mo钢的静态再结晶影响最大,增大变形量可获得均匀细小的晶粒组织;变形温度和间隔时间次之;应变速率及初始奥氏体晶粒尺寸的影响较小。根据实验结果,建立23Co13Ni11Cr3Mo钢静态再结晶晶粒尺寸模型,定量分析起落架在锤锻压机上整体模锻成形过程的组织演化,发现在变形不充分的条件下静态再结晶是导致起落架锻件晶粒不合格的原因。模型预测结果与实验结果吻合较好。     

WNQ570桥梁钢的静态再结晶行为

 为了研究轧制工艺对WNQ570桥梁钢再结晶行为的影响,采用Gleeble-3500热模拟试验机模拟了其双道次热变形过程,测试了试验钢的应力-应变曲线,建立了静态再结晶晶粒体积分数随变形温度和道次间隔时间变化的关系模型,分析了应变诱导析出抑制对静态软化行为的影响。研究结果表明：静态再结晶体积分数随变形温度的提高或道次间隔时间的延长而增大,应变诱导析出抑制静态再结晶的进行;静态再结晶激活能为240.47kJ/mol。研究结果为制订试验钢二阶段控轧工艺提供了依据。     

高Ti微合金钢热变形奥氏体的静态再结晶行为

在Gleeable-3800热/力模拟试验机上采用双道次压缩法,研究了一种高Ti微合金钢在奥氏体区变形后道次间隔时间内的静态软化行为,分析了变形温度和间隔时间对静态再结晶行为的影响规律,采用应力补偿法计算了静态再结晶分数。结果表明,变形温度、道次间隔时间对Ti微合金钢静态再结晶行为影响显著,变形温度越高,间隔时间越长,静态再结晶进行得越迅速;确定了Ti微合金钢的静态再结晶激活能为412.56 k J/mol,同时建立了静态再结晶动力学模型。     

X70管线钢热变形奥氏体的静态再结晶行为

通过双道次压缩实验,在Gleeble1500热模拟试验机上研究了X70管线钢在不同变形工艺下奥氏体的软化行为,分析了不同变形温度、间隔时间、应变速率、变形量及初始奥氏体晶粒尺寸等参数对静态再结晶行为的影响规律,采用应力补偿法计算了不同变形条件下的静态再结晶百分率.根据实验数据,计算出X70管线钢静态再结晶激活能为435.3kJ·mol^-1,建立了其静态再结晶动力学模型.     

曲轴用非调质钢C38N2的静态再结晶行为

通过热模拟实验、光学金相及透射电镜分析观察,研究了奥氏体化条件、变形温度、变形速率、变形量以及道次间隔时间对曲轴用非调质钢C38N2轧制道次间的静态再结晶体积分数和残余应变率的影响规律.实验结果表明：随着变形温度的升高、变形速率的增大、变形量的增大或道次间间隔时间的增长,静态再结晶的体积分数逐渐升高,道次的残余应变率逐渐降低;原始奥氏体晶粒尺寸增大,静态再结晶体积分数降低,但变化不大;在1250℃以下,随着奥氏体化温度的升高,静态再结晶体积分数降低不明显,但在1250℃以上,奥氏体化温度的升高明显降低了静态再结晶体积分数.通过线性拟合以及最小二乘法,得到静态再结晶体积分数与不同变形工艺参数之间关系的数学模型;对已有残余应变率数学模型进行修正,得到含有应变速率项的残余应变率数学模型,拟合度较好.     

两种高等级管线钢的奥氏体热变形行为

利用MMS300热模拟试验机在温度为850~1 150℃,应变速率为5 s-1,道次间隔时间为1~400 s的条件下进行了X80及X100管线钢双道次压缩变形试验,测定了不同间隔时间、不同变形温度条件下的软化率。研究结果表明：当道次间隔时间相同时,随变形温度升高,X80及X100管线钢静态再结晶分数均增加,再结晶进程加...     

L360管线钢热轧过程静态再结晶行为的研究

奥氏体再结晶行为是影响热轧钢带组织和力学性能的1个主要因素。在热模拟试验的基础上,采用应力松弛法和显微组织观察法,对含Nb和Ti的L360管线钢热轧过程奥氏体静态再结晶行为进行了研究,分析了应变、变形温度、应变速率、原始奥氏体晶粒尺寸对奥氏体静态再结晶的影响。利用线性回归分析,计算出试验钢静态再结晶激活能为203kJ;同时通过回归,得出试验钢热轧过程静态再结晶动力学方程。     

Recrystailization Behavior of Deformed Austenite in High Strength Microalloyed Pipeline Steel

Using methods of single-hit hot compression and stress relaxation after deformation on a Gleeble 1500D thermomechanical simulator,the curves of flow stress and stress relaxation,the microstructure and the recrystallization behavior of Nb-V-Ti high strength microalloyed low carbon pipeline steel were studied,and the influence of the thermomechanical treatment parameters on dynamic and static recrystallization of the steel was investigated.It was found that microalloying elements improved the deformation activation energy and produced a retardation of the recrystallization due to the solid solution and precipitation pinning.The deformation conditions such as deformation temperature,strain,and strain rate influenced the recrystallization kinetics and the microstructure respectively.Equations obtained can be used to valuate and predict the dynamic and static recrystallizations.     

Recrystallization Behavior of Deformed Austenite in High Strength Microailoyed Pipeline Steel

Using methods of single-hit hot compression and stress relaxation after deformation on a Gleeble 1500D thermomechanical simulator, the curves of flow stress and stress relaxation, the microstructure and the recrystallization behavior of Nb-V-Ti high strength microalloyed low carbon pipeline steel were studied, and the influence of the thermomechanical treatment parameters on dynamic and static recrystallization of the steel was investigated. It was found that microalloying elements improved the deformation activation energy and produced a retardation of the recrystallization due to the solid solution and precipitation pinning. The deformation conditions such as deformation temperature, strain, and strain rate influenced the recrystallization kinetics and the microstructure respectively. Equations obtained can be used to valuate and predict the dynamic and static recrystallizations.     

Recrystallization Behavior of Deformed Austenite in High Strength Microalloyed Pipeline Steel

 Using methods of single hit hot compression and stress relaxation after deformation on a Gleeble 1500D thermomechanical simulator, the curves of flow stress and stress relaxation, the microstructure and the recrystallization behavior of Nb V Ti high strength microalloyed low carbon pipeline steel were studied, and the influence of the thermomechanical treatment parameters on dynamic and static recrystallization of the steel was investigated. It was found that microalloying elements improved the deformation activation energy and produced a retardation of the recrystallization due to the solid solution and precipitation pinning. The deformation conditions such as deformation temperature, strain, and strain rate influenced the recrystallization kinetics and the microstructure respectively. Equations obtained can be used to valuate and predict the dynamic and static recrystallizations.     

Static Recrystallization Kinetics Model After Hot Deformation of Low-Alloy Steel Q345B

The static recrystallization behavior of low-alloy steel Q345B during double-pass hot compression deformation tests was investigated in the temperature range of 900-1000 ℃,the true strain range of 0.15-0.25 and the interpass time range of 0.5-50 s on Gleeble-3500 thermo-simulation machine.The results show that static recrystallization during the interpass time is observed.As the deformation temperature and strain increase,softening caused by static recrystallization is obvious.According to the analysis and calculation of thermo-simulation data,the static recrystallization activation energy was obtained and static recrystallization kinetics model was built.Finally,the error analysis of static recrystallization kinetics model proved that the model had good accuracy.Therefore,this model provides a theoretical basis for static recrystallization(SRX)and will contribute to the development of multipass hot rolling process,in order to control the rolling process more accurately.     

Static Recrystallization Behavior of 316LN Austenitic Stainless Steel

The static recrystallization of 316LN austenitic stainless steel was studied by double-pass hot compression tests on a Gleeble-3500 thermomechanical simulator. The specimens were compressed at the deformation temperatures of 950, 1050, 1150 °C, strain rates of 0.01, 0.1, 1s^?1, strains of 0.1, 0.15, 0.2, and intervals of 1 — 100 s. The results show that the volume fraction of static recrystallization of 316LN increases with the increase of deformation temperature, strain rate, strain and interval, which indicates that static recrystallization occurs easily under the conditions of higher deformation temperature, higher strain rate and larger strain. Deformation temperature has significant influence on static recrystallization of 316LN. The volume fraction of static recrystallization could easily reach 100% at higher deformation temperatures. By microstructure analysis, it can be concluded that the larger the volume fraction of static recrystallization, the more obvious the grain refinement. The static recrystallization activation energy of 317 882 J/mol and the exponent n of 0.46 were obtained. The static recrystallization kinetics was established. The predicted volume fraction of static recrystallization is in good agreement with the experimental results.