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Elastic-viscoplastic constitutive equations of K439B superalloy and thermal stress simulation during casting process

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中国铸造:英文版 2023年第5期20卷 403-413页

作者： da-shan sui Yu shan Dong-xin Wang Jun-yi Li Yao Xie Yi-qun Yang An-ping Dong Bao-de Sun Institute of Forming Technology&Equipment School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200030China State Key Laboratory of Special Rare Metal Materials Northwest Rare Metal Materials Research Institute Ningxia Co.Ltd.Shizuishan 753000NingxiaChina shanghai Key Laboratory of Advanced High-temperature Materials and Precision Forming School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China

K439B nickel-based superalloy is a new type of high-temperature material.There is insufficient research on its constitutive equations and numerical modeling of thermal stress.Isothermal tensile experiments of K439B superalloy at different temperatures(20°C-1,000°C)and strain rates(1.33×10^(-3)s^(-1)-5.33×10^(-3)s^(-1))were performed by using a Gleeble-3800 simulator.The elastic moduli at different temperatures(20°C-650°C)were measured by resonance method.Subsequently,stress-strain curves were measured for K439B superalloy under different conditions.The elastic-viscoplastic constitutive equations were established and the correspongding parameters were solved by employing the Perzyna model.The verification results indicate that the calculated values of the constitutive equations are in good agreement with the experimental values.On this basis,the influence of process parameters on thermal stress was investigated by numerical simulation and orthogonal experimental design.The results of orthogonal experimental design reveal that the cooling mode of casting has a significant influence on the thermal stress,while pouring temperature and preheating temperature of shell mold have minimal impact.The distribution of physical fields under optimal process parameters,determined based on the orthogonal experimental design results,was simulated.The simulation results determine separately the specific positions with maximum values for effective stress,plastic strain,and displacement within the casting.The maximum stress is about 1,000.0 MPa,the plastic strain is about 0.135,and the displacement is about 1.47 mm.Moreover,the distribution states of thermal stress,strain,and displacement are closely related to the distribution of the temperature gradient and cooling rate in the casting.The research would provide a theoretical reference for exploring the stress-strain behavior and numerical modeling of the effective stress of the alloy during the casting process.

关键词： nickel-based superalloy investment casting Perzyna model elastic-viscoplastic thermal stress numerical simulation

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Numerical Simulation of Microstructure Evolution for SA508-3 Steel during Inhomogeneous Hot Deformation Process

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Journal of Iron and Steel Research(International) 2014年第11期21卷 1022-1029页

作者： da-shan sui Fei CHEN Pei-pei ZHANG Zhen-shan CUI National Die & Mold CAD Engineering Research Center Shanghai Jiao Tong University

Based on hot compression tests by a Gleeble-1500D thermo-mechanical simulator, the flow stress model and microstructure evolution model for SA508-3 steel were established through the classical theories on work hardening and softening. The developed models were integrated into 3D thermal-mechanical coupled rigid plastic finite element software DEFORM3D. The inhomogeneous hot deformation （IHD） experiments of SA508 3 steel were designed and carried out. Meanwhile, numerical simulation was implemented to investigate the effect of temperature, strain and strain rate on microstructure during IHD process through measuring grain sizes at given positions. The simulated grain sizes were basically in agreement with the experimental ones. The results of experiment and simulation demonstrated that temperature is the main factor for the initiation of dynamic recrystallization （DRX）, and higher temperature means lower critical strain so that DRX can be facilitated to obtain uniform fine microstructure.

关键词： SA508-3 steel inhomogeneous hot deformation microstructure evolution grain size numerical simulation

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Effects of process parameters on fragment and refinement of millimeter- grade coarse grains for 316LN steel during hot cogging

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Journal of Iron and Steel Research(International) 2017年第5期24卷 529-535页

作者： da-shan sui Hai-ming Zhang Hong-yang Zhu Zhe Zhu Zhen-shan Cui National Die & Mold CAD Engineering Research Center Shanghai Jiao Tong University Shanghai 200030 China shanghai Heavy Machinery Plant Shanghai 200245 China

The heterogeneous mixed-grain microstructure is a common defect for the heavy forging of 316LN austenitie stainless steel. Isothermal compression experiments were performed on a Gleeble-3500 thermo-mechanical simulator to investigate the effect of process parameters on the fragment and re- finement of millimeter-grade coarse grains （MCGs） during hot cogging. The experimental results in- dicate that the stress of MCG specimens is much larger than that of fine grain （FG） ones at 1150 ℃, while the stress difference between MCG and FG samples became smaller at 1200 ℃. Moreover, the MCGs can be well fragmented and refined under the condition of temperature of 1200 ℃, strain rate of 0.01 s-1 , and reduction rate of 50%. Meanwhile, numerical simulations were conducted to study the influences of temperature, strain and strain rate on microstructure evolution. The results of ex- periments and simulations comprehensively demonstrate that the MCG results in the increase of de- formation resistance and incompatibility of deformation, and it can be fragmented and refined at 1200 ℃ so that the plastic deformation energy decreases remarkably with the increase of temperature from 1 150 to 1200 ℃.

关键词： 316LN steel Hot deformation Coarse grain Microstrueture evolution Numerical simulation

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亚共晶合金晶粒尺寸与相图变量相关双参数模型的检验

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Transactions of Nonferrous Metals Society of China 2024年第6期34卷 1721-1733页

作者：隋大山 Qing-you HAN 上海交通大学材料科学与工程学院塑性成形与装备研究院上海200030 东南大学机械工程学院南京211189 School of Engineering Technology Purdue UniversityWest LafayetteIN 47906USA

提出用于描述晶粒尺寸与工艺条件和相图变量相关联的简单双参数数学模型,然而,这些模型还没有通过良好的实验数据进行充分检验。采用精选的亚共晶合金实验数据检验这些模型,并提出实验数据的选择标准。采用这些双参数模型拟合被选择的... 详细信息

提出用于描述晶粒尺寸与工艺条件和相图变量相关联的简单双参数数学模型,然而,这些模型还没有通过良好的实验数据进行充分检验。采用精选的亚共晶合金实验数据检验这些模型,并提出实验数据的选择标准。采用这些双参数模型拟合被选择的实验数据,检查曲线的拟合质量和适用性,从而确定与实验数据吻合更好的数学模型。基于数据分析,探讨溶质元素细化晶粒尺寸的机理。结果表明,晶粒尺寸与合金凝固间隔之间存在明确的依赖关系,这种关系可采用P变量加以描述。晶粒尺寸对凝固间隔的这种明显依赖表明,在充型和凝固过程存在对流的铸锭和铸件中,与枝晶破碎有关的机理是控制溶质元素细化晶粒的主要运行机制。

关键词：凝固组织晶粒细化溶质元素数学模型相图变量晶粒尺寸亚共晶合金

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Microstructural characteristics and mechanical properties of bronze/steel bimetallic laminated composite prepared by protective atmosphere casting process

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China Foundry 2021年第5期18卷 497-504页

作者： Bin Liu da-shan sui Zhi-min Guo Yuan-long Wang Xiao-lin Yang Guang-hong Hu Ji-xian Zhang Chang-zeng Luo Research Institute of Hydraulic Transmission Linde Hydraulics(China)Co.Ltd.Weifang 261061ShandongChina National Engineering Research Center of Die&Mold CAD Shanghai Jiao Tong UniversityShanghai 200030China

The bonding quality of bronze/steel bimetallic laminated composite is the key factor to whether it can be used in poor working conditions.In this study,bimetallic billets were prepared by the protective atmosphere casting process.The microstructural characteristics,mechanical properties and interface bonding mechanism of the bronze/steel bimetallic composites were analyzed comprehensively through a series of microstructure analysis(inicluding OM,SEM,and EDS)and mechanical properties tests.The experimental results demonstrate that the vaporization of lead(Pb)element in the bronze is only 0.4%in weight,and alloy elements are diffused into both sides at the interface.Moreover,the hardness in the bronze region exceeds 100.0 HV which indicates excellent wear resistance.Tensile and shear tests indicate that the fractures mainly occur on the bronze side with the interaction of the brittle fracture of Pb particles and the ductile fracture of Cu-Sn solid solution.The maximum tensile strength and shear strength reach 204.0 MPa and 211.0 MPa,respectively.These results demonstrate that the protective atmosphere casting process is applicable for the preparation of bronze/steel bimetallic laminated composite with high quality.

关键词： protective atmosphere casting process lead bronze bimetallic composite microstructure mechanical properties

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What induced the trend shift of mixed-layer depths in the Antarctic Circumpolar Current region in the mid-1980s?

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Acta Oceanologica Sinica 2024年第1期43卷 11-21页

作者： shan Liu Jingzhi Su Huijun Wang Cuijuan sui Key Laboratory of Marine Hazards Forecasting National Marine Environmental Forecasting CenterMinistry of Natural ResourcesBeijing 100081China Center for Earth System Modeling and Prediction of CMA Beijing 100081China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science&TechnologyNanjing 210044China Nansen-Zhu International Research Center Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China

An obvious trend shift in the annual mean and winter mixed layer depth(MLD)in the Antarctic Circumpolar Current(ACC)region was detected during the 1960–2021 period.Shallowing trends stopped in mid-1980s,followed by a period of weak trends.The MLD deepening trend difference between the two periods were mainly distributed in the western areas in the Drake Passage,the areas north to Victoria Land and Wilkes Land,and the central parts of the South Indian sector.The newly formed ocean current shear due to the meridional shift of the ACC flow axis between the two periods is the dominant driver for the MLD trends shift distributed in the western areas in the Drake Passage and the central parts of the South Indian sector.The saltier trends in the regions north to Victoria Land and Wilkes Land could be responsible for the strengthening mixing processes in this region.

关键词： mixed layer depth trend shift Antarctic Circumpolar Current(ACC) flow axis

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Influence of the Atlantic Multidecadal Oscillation and Interdecadal Pacific Oscillation on Antarctic surface air temperature during 1900 to 2015

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Acta Oceanologica Sinica 2024年第3期43卷 48-58页

作者： Cuijuan sui Lejiang Yu Alexey YuKarpechko Licheng Feng shan Liu Key Laboratory of Marine Hazards Forecasting National Marine Environmental Forecasting CenterMinistry of Natural ResourcesBeijing 100081China Key Laboratory for Polar Science Polar Research Institute of ChinaMinistry of Natural ResourcesShanghai 200136China Finnish Meteorological Institute HelsinkiFI-00101Finland

The importance of the Atlantic Multidecadal Oscillation(AMO)and Interdecadal Pacific Oscillation(IPO)in influencing zonally asymmetric changes in Antarctic surface air temperature(SAT)has been established.However,previous studies have primarily concentrated on examining the combined impact of the contrasting phases of the AMO and IPO,which have been dominant since the advent of satellite observations in 1979.This study utilizes long-term reanalysis data to investigate the impact of four combinations of+AMO+IPO,–AMO–IPO,+AMO–IPO,and–AMO+IPO on Antarctic SAT over the past 115 years.The+AMO phase is characterized by a spatial mean temperature amplitude of up to 0.5℃over the North Atlantic Ocean,accompanied by positive sea surface temperature(SST)anomalies in the tropical eastern Pacific and negative SST anomalies in the extratropical-mid-latitude western Pacific,which are indicative of the+IPO phase.The Antarctic SAT exhibits contrasting spatial patterns during the+AMO+IPO and+AMO–IPO periods.However,during the–AMO+IPO period,apart from the Antarctic Peninsula and the vicinity of the Weddell Sea,the entire Antarctic region experiences a warming trend.The most pronounced signal in the SAT anomalies is observed during the austral autumn,whereas the combination of–AMO and–IPO exhibits the smallest magnitude across all the combinations.The wavetrain excited by the SST anomalies associated with the AMO and IPO induces upper-level and surface atmospheric circulation anomalies,which alter the SAT anomalies.Furthermore,downward longwave radiation anomalies related to anomalous cloud cover play a crucial role.In the future,if the phases of AMO and IPO were to reverse(AMO transitioning to a negative phase and IPO transitioning to a positive phase),Antarctica could potentially face more pronounced warming and accelerated melting compared to the current observations.

关键词： Atlantic Multidecadal Oscillation(AMO) Interdecadal Pacific Oscillation(IPO) surface air temperature Antarctic wavetrain Rossby wave source

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基于空间分辨法分析时间低相干光自聚焦效应

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物理学报 2024年第9期73卷 36-45页

作者：单翀孔令豹崔勇季来林赵晓晖李福建饶大幸赵元安隋展邵建达复旦大学信息科学与工程学院超精密光学制造工程技术研究中心上海201203 中国工程物理研究院上海激光等离子体研究所上海201800 中国科学院上海光学精密机械研究所强激光材料重点实验室上海201800

时间低相干光由于其瞬时宽带的物理特性,在激光惯性约束聚变中得到了广泛的关注.然而其复杂的时间尖峰结构或将诱导非线性自聚焦效应的放大.同时,传统的非线性自聚焦特征数值的测试方法中,多数材料的表面损伤先于体内自聚焦成丝损伤发生... 详细信息

时间低相干光由于其瞬时宽带的物理特性,在激光惯性约束聚变中得到了广泛的关注.然而其复杂的时间尖峰结构或将诱导非线性自聚焦效应的放大.同时,传统的非线性自聚焦特征数值的测试方法中,多数材料的表面损伤先于体内自聚焦成丝损伤发生,这为对比不同激光的非线性效应带来巨大影响.本文利用短焦距透镜对熔石英进行紧聚焦,通过调节入射激光能量,在避免前表面损伤的前提下,诱导熔石英产生自聚焦成丝损伤.随后通过理论计算对光束在样品体内传输过程的光斑变化进行空间分辨处理,并得到对应细分位置的非线性数值.最终将各个位置对应的非线性相位变化值进行积分,得到前表面无损条件下材料的非线性自聚焦特征数值.测试结果表明时间低相干光的非线性自聚焦效应比传统单模脉冲激光更强.本文不仅设计了一套更加精确的对比不同激光非线性效应的测试方法,同时也探明了时间相干性对于非线性自聚焦效应的影响机制,为高功率时间低相干激光器的设计提供理论依据和参考.

关键词：惯性约束核聚变时间低相干光非线性自聚焦特征数值空间分辨法

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双金属复合铸造界面结合技术与机理研究

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铸造 2024年第1期73卷 1-8页

作者：韩青有隋大山刘兴涛孙东科东南大学机械工程学院江苏南京211189 上海交通大学材料科学与工程学院上海200030

目前常用的复合铸造方法难以制造出具有优质冶金结合的双金属铸件。采用康明斯技术研究钢棒和铝铸件结合,系统研究了工艺参数和超声辅助技术对钢铝双金属冶金结合质量的作用规律。试验结果表明,工艺参数对冶金结合的质量有着显著的影响... 详细信息

目前常用的复合铸造方法难以制造出具有优质冶金结合的双金属铸件。采用康明斯技术研究钢棒和铝铸件结合,系统研究了工艺参数和超声辅助技术对钢铝双金属冶金结合质量的作用规律。试验结果表明,工艺参数对冶金结合的质量有着显著的影响。使用高强超声波辅助复合铸造技术时,即使使用钢棒和未经除气处理的铝合金液,仍能制备出具有高质量冶金结合的双金属复合铸件。结合数值模拟技术,探索了复合铸造过程中双金属界面气隔形成的原因和冶金结合形成条件,提出了获得优质冶金界面结合的物理、热力学和动力学条件。

关键词：复合铸造冶金结合铸造缺陷数值模拟

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大豆蛋白强化羧甲基纤维素钠复合油凝胶的性能

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食品科学 2024年第4期45卷 60-67页

作者：崔梦琦单冠程孙若涵田波隋晓楠东北农业大学食品学院黑龙江哈尔滨150030

利用气凝胶模板法可间接制备油凝胶,该方法具有制备简单、性能优异等优点而被广泛关注。本研究通过静电相互作用制备了羧甲基纤维素钠(carboxy methyl cellulose-Na,CMC-Na)/大豆分离蛋白(soybean protein isolate,SPI)复合气凝胶,探究... 详细信息

利用气凝胶模板法可间接制备油凝胶,该方法具有制备简单、性能优异等优点而被广泛关注。本研究通过静电相互作用制备了羧甲基纤维素钠(carboxy methyl cellulose-Na,CMC-Na)/大豆分离蛋白(soybean protein isolate,SPI)复合气凝胶,探究不同蛋白含量对气凝胶平均粒径、微观结构、红外光谱、吸油动力学、吸油和持油能力的影响。并基于气凝胶模板制备油凝胶,对其质构性能、抑菌性能以及贮藏稳定性进行表征。结果表明,SPI和CMC-Na依靠静电吸附形成了稳定的复合物,平均粒径随着蛋白含量的增加而增大。复合气凝胶显示出更加致密的多孔网络结构,持油能力得到增强,但不利于吸油性能的改善。同时,蛋白的加入提高了油凝胶的强度,增加了杨氏模量,并改善了油凝胶的抑菌效果和贮藏稳定性。因此,气凝胶模板法可视为制备油凝胶的良好方法,并且基于多糖蛋白静电吸附可以制备稳定的油凝胶体系。

关键词：羧甲基纤维素钠大豆分离蛋白静电吸附气凝胶模板油凝胶

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