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熔模铸件尺寸控制的数字孪生建模关键技术与应用

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金属学报 2024年第4期60卷 548-558页

作者：官邦汪东红马洪波疏达丁正一崔加裕孙宝德上海交通大学材料科学与工程学院上海市先进高温材料及其精密成形重点实验室上海200240 上海交通大学金属基复合材料国家重点实验室上海200240 西安电子科技大学机电工程学院西安710126

熔模铸造工艺流程长、工序多,铸件成型过程孤岛控制,存在尺寸超差问题。本工作基于节点法向量和最近邻点,提出熔模铸造工艺全节点位移传递的计算方法,解决熔模铸件成型多流程的数据孤岛问题。研究蜡模注射成型和铸件凝固过程工艺参数-... 详细信息

熔模铸造工艺流程长、工序多,铸件成型过程孤岛控制,存在尺寸超差问题。本工作基于节点法向量和最近邻点,提出熔模铸造工艺全节点位移传递的计算方法,解决熔模铸件成型多流程的数据孤岛问题。研究蜡模注射成型和铸件凝固过程工艺参数-尺寸偏差的关系,为数字孪生建模提供数据模型。对环套环特征件建立铸件模具反变形设计和铸件多流程下工艺优化的数字孪生应用。该数字孪生模型应用于设计阶段,反变形设计出模具内腔的三维几何模型。模拟结果表明,铸件所有节点位移偏差在0.04 mm以下。应用于流程之间的工艺控制,根据前一工序下尺寸偏差,进行后续工艺优化调控。

关键词：熔模铸造尺寸传递反变形设计数字孪生智能铸造

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镍基高温合金反重力铸造压力曲线设计与验证

航空材料学报 2024年第2期44卷 143-150页

作者：隋大山麻晋源许圆王迪董安平孙宝德上海交通大学材料科学与工程学院塑性成形技术与装备研究院上海200030 上海工程技术大学材料科学与工程学院上海201620 上海交通大学材料科学与工程学院上海市先进高温材料与精密成形重点实验室上海200240

针对镍基高温合金反重力铸造工艺中传统压力曲线设计方法的不足,充分考虑铸件沿充型方向的变截面结构特征,通过CAD软件的二次开发,实现铸件截面积的自动计算,以定量化描述铸件的截面变化特征。基于伯努利方程和流量守恒方程,推导出充型... 详细信息

针对镍基高温合金反重力铸造工艺中传统压力曲线设计方法的不足,充分考虑铸件沿充型方向的变截面结构特征,通过CAD软件的二次开发,实现铸件截面积的自动计算,以定量化描述铸件的截面变化特征。基于伯努利方程和流量守恒方程,推导出充型压力与金属液面上升速度之间的关系,提出基于铸件截面积自动计算的新型压力曲线设计方法。在此基础上,对镍基高温合金铸件的反重力铸造过程进行数值分析。充型模拟结果表明:与传统压力曲线设计方法相比,新型设计方法确定的压力曲线能使最小截面处充型速度峰值由0.611 m/s降至0.439 m/s,降幅达28.15%,有效避免金属液震荡和飞溅;同时可缩短充型时间,确保金属液快速平稳充型。水力学实验和浇注实验表明,新型压力曲线的充型液面更平稳,能有效抑制铸造缺陷,证明新型压力曲线设计方法的有效性,为合理设计反重力压力曲线提供依据。

关键词：镍基高温合金反重力铸造压力曲线变截面数值模拟

Atomic scale visualizations of low-angle grain boundary mediated plasticity by coupled dislocation climb and glide in nanoporous gold

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Nano Research 2023年第2期16卷 2622-2629页

作者： Shufen Chu Junnan Jiang Xiaoran Zhao baode sun Pan Liu Shanghai Key Laboratory of Advanced High-temperature Materials and Precision Forming State Key Laboratory of Metal Matrix CompositesSchool of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China

Grain boundaries(GBs),as a prevalent structural characteristic,play a crucial role in the deformation of nanoporous metals with nanosized grains and ***,the fundamental understanding of GB-mediated deformation is still lacking because the plastic behavior of discrete ligaments involving GBs remains to be ***,we report atomic scale visualizations of coupled GB dislocation climb and glide in nanoporous gold ligaments with low-angle GBs via in situ tensile straining inside a Cs-corrected transmission electron *** zig-zag motion paths of GB dislocations are precisely determined by real-time tracking of the movements of dislocation *** concurrent climb and glide of the dislocation arrays are confined to a narrow GB region,greatly enhancing GB diffusion in the bicrystal *** findings of coupled dislocation climb and glide shine a light on the room-temperature deformation of nanoporous metals and provide a time-dependent atomic-level physical image for GB engineering.

关键词： nanoporous gold dislocation climb dislocation glide low-angle grain boundaries

Effects of a high magnetic field on single-phase interface evolution,additional interfacial energy and nucleation undercooling in Al-based alloy

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Journal of Materials Science & Technology 2023年第23期154卷 43-53页

作者： Lin Wang Zhipeng Long Long Hou Song Yan baode sun Xi Li Shanghai Key Lab of Advanced High-temperature Materials and Precision Forming Shanghai Jiao Tong University Shanghai 200240 China State Key Laboratory of Advanced Special Steels Shanghai University Shanghai 200072 China

The effects of a high magnetic field on the evolution of the single-phase interface and the liquid-solid interface energy in Al-Cu alloy were investigated *** is found that the application of the magnetic field has a significant promotion effect on the migration of liquid droplets,accelerating the formation of the single-phase *** should be attributed to the thermoelectric(TE)magnetic convection in the droplets which has enhanced the diffusion and increased the migration speed of liquid ***,the effect of the high magnetic field on the solid-liquid interface energy is analyzed by an improved grain boundary groove(GBG)*** average solid-liquid interface energy of theα-Al/Al-Cu and Al2Cu/Al-Cu systems increases and decreases with the increase of the magnetic field,*** above experiment results are well explained based on the formation and interaction of the magnetic dipole at the solid-liquid ***,experimental results reveal that the magnetic-field-induced interface energy increases and decreases the nucleation undercooling of the Al-30wt.%Cu alloy and Al-35wt.%Cu alloy,*** studying the effect of the magnetic-field-induced interface energy on the nucleation undercooling,the understanding of the interface energy-induced nucleation undercooling deepens.

关键词： High magnetic field Interface energy Nucleation undercooling Grain boundary groove

Effects of V addition on the mechanical properties at elevated temperatures in a γ”-strengthened NiCoCr-based multi-component alloy

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Journal of Materials Science & Technology 2022年第12期107卷 290-300页

作者： Yunwei Pan Anping Dong Yang Zhou Dafan Du Donghong Wang Guoliang Zhu baode sun Shanghai Key Lab of Advanced High-temperature Materials and Precision Forming School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China State Key Lab of Metal Matrix Composites Shanghai Jiao Tong UniversityShanghai 200240China

Ni Co Cr-based multi-component alloys have drawn much attention due to their exceptional ductility and strain hardening ***,insufficient strength-ductility synergy of NiCoCr alloy has always been an issue that prevents it from extensive *** to our previous research,the precipitation ofγ”phase can significantly improve the strength-ductility synergy of this alloy system at room *** this study,the effects of V addition onγ”phase stability and high-temperature mechanical properties have been explicitly *** results indicate that V addition can stabilize the metastableγ”phase in this alloy system and prevent it from transforming into a stableδphase at grain boundaries upon 650℃aging,resulting in improved mechanical properties at elevated *** specific strength ofγ”-strengthened multi-component NiCoCr-based alloy can reach up to 86.2 MPa gcmat 650℃,which is higher than those of Ni-based superalloys,IN 939 and *** work provides theoretical guidance for the novel design of γ”-strengthened alloy for high-temperature applications.

关键词： Multi-component alloys CALPHAD γ”phase Microstructural evolution High-temperature mechanical properties

航空发动机用高温合金复杂薄壁精密铸件尺寸精度控制技术研究进展

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航空材料学报 2024年第2期44卷 31-44页

作者：崔加裕汪东红肖程波疏达孙宝德官邦丁正一上海交通大学材料科学与工程学院上海市先进高温材料及其精密成形重点实验室上海200240 中国航发北京航空材料研究院先进高温结构材料重点实验室北京100095

高温合金主要应用于涡轮后机匣、扩压器、预旋喷嘴等航空关键热端部件,采用整体精密铸造技术取代“分体铸造+焊接”成形方法,可减少零件数量和加工工序、提升可靠性、减轻质量,是航空发动机先进材料加工关键核心技术之一。然而复杂薄壁... 详细信息

高温合金主要应用于涡轮后机匣、扩压器、预旋喷嘴等航空关键热端部件,采用整体精密铸造技术取代“分体铸造+焊接”成形方法,可减少零件数量和加工工序、提升可靠性、减轻质量,是航空发动机先进材料加工关键核心技术之一。然而复杂薄壁构件液态精密成型存在尺寸超差难题,导致发动机气动性能降低,装配精度下降,是长期制约我国航空发动机关键构件制造质量的瓶颈问题。本文综述目前国内外在高温合金精密铸造尺寸精度控制方面的研究进展,并对基于数字化和智能化技术的发展趋势进行了前瞻性分析和探讨,未来迫切需要构建液态精密成型数字孪生平台,发展更先进的尺寸变形精准定量智能预测方法以及压蜡模具内腔型面设计理论。

关键词：航空发动机高温合金尺寸精度控制熔模精密铸造复杂薄壁

Dislocation glide and mechanical twinning in a ductile VNbTi medium entropy alloy

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Journal of Materials Science & Technology 2022年第15期110卷 210-215页

作者： Mingxu Wu Shubin Wang Fei Xiao Guoliang Zhu Chao Yang Da Shu baode sun Shanghai Key Lab of Advanced High-temperature Materials and Precision Forming and State Key Lab of Metal Matrix Composites School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China

An equiatomic VNbTi medium-entropy alloy with outstanding tensile properties and unique deformation behavior is *** screw dislocation glide,deformation twinning,and dislocation accumulation induced kink bands are identified as three deformation mechanisms that contribute to a large elongation above 20%.The{112}twins are activated at the beginning of the yield stage accompanied by sudden stress-drop and pronounced acoustic *** dominate subsequent tensile deformation,and the prevalent multiplanar dislocation slip promotes the formation of complex dislocation configurations(e.g.,debris,dipoles,and loops)and dense dislocation *** twin bands and kink bands can further impede the dislocation motion meanwhile effectively alleviate stress *** synergistic activation of these deformation mechanisms provides new opportunities to design ductile refractory medium-and high-entropy alloys.

关键词： Medium-entropy alloy Mechanical twinning Screw dislocation Multiplanar slip Tensile deformation

Atomic insights into heterogeneous nucleation and growth kinetics of Al on TiB_(2) particles in undercooled Al-5Ti-1B melt

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Journal of Materials Science & Technology 2023年第25期156卷 72-82页

作者： Jing Feng Yanfeng Han Xiaocang Han Xiaodong Wang Shuangxi Song baode sun Mingwei Chen Pan Liu Shanghai Key Laboratory of Advanced High-temperature Materials and Precision Forming State Key Laboratory of Metal Matrix Composites School of Materials Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China Department of Materials Science and Engineering Johns Hopkin UniversityBaltimoreMD 21218USA

Titanium diboride(TiB_(2))is an effective grain refiner of Al alloys in the industry that facilitates casting processes by forming uniformly refined *** our understanding of the underlying refinement mechanisms has advanced,the atomic kinetics of heterogeneous nucleation of Al on TiB2 remains ***,we report atomic-scale observations of the heterogeneous nucleation and growth kinetics of Al on self-formed TiB_(2) particles by in situ heating of undercooled Al-5Ti-1B *** demonstrate that an ordered Al monolayer forms on the Ti-terminated{0001}TiB_(2) surface;then,the surrounding Al atoms are initiated to form an island-shaped Al nucleus with face-centered cubic{111}stacking without the assistance of a Ti-rich buffer *** interfacial lattice mismatch between{111}Al and{0001}TiB_(2) causes remarkable out-of-plane strain that decreases gradually with Al nucleus layers increasing to 6 atomic *** elastic strain energy originating from this interfacial strain increases the free energy of the Al/TiB2 heterostructure,hence impeding the rapid growth of the Al *** found that TiB2 particles stabilize the Al nuclei rather than activating their free growth into grains when the experimental undercoolingΔT is lower than the onset undercoolingΔT fg in Greer's free growth *** findings provide an atomic-scale physical image of the heterogeneous nucleation and growth mechanisms of Al with inoculator participation and elucidate the strain-dependent growth kinetics of Al nuclei.

关键词： In situ tem Heterogeneous nucleation Lattice strain Aluminum TiB2 particles

Microstructural Characteristics and Mechanical Properties of Cast Mg–3Nd–3Gd–xZn–0.5Zr Alloys

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Acta Metallurgica Sinica(English Letters) 2022年第6期35卷 922-940页

作者： He Xie Guohua Wu Xiaolong Zhang Zhongquan Li Wencai Liu Liang Zhang Xin Tong baode sun National Engineering Research Center of Light Alloy Net Forming and State Key Laboratory of Metal Matrix Composites School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China Shanghai Spaceflight Precision Machinery Institute Shanghai 201600China

The microstructure,aging behavior and mechanical properties of cast Mg–3Nd–3Gd–x Zn–0.5Zr(x=0,0.5,0.8,1 wt%)alloys are investigated in this ***–Zr particles with different morphologies form during solution treatment due to the additions of *** the Zn content increases,the number density of Zn–Zr particles also *** comparisons of peak-aged studied alloys indicate that varying Zn additions could profoundly influence the competitive precipitation *** the peak-aged Zn-free alloy,β′′phases are the key strengthening *** 0.5 wt%Zn is added,besidesβ′′precipitates,additional fineβ_(1)precipitates *** the addition of 0.8 wt%Zn,the peak-aged 0.8Zn alloy is characterized by predominantly prismaticβ_(1)and scanty basal precipitate *** enhanced precipitation ofβ_(1)should be primarily attributable to the presence of increased Zn–Zr *** Zn content further increases to 1 wt%,the precipitation of basal precipitates is markedly *** precipitates andβ_(1)phases are the key strengthening precipitates in the peak-aged 1Zn *** tests reveal that the relatively best tensile properties are achieved in the peak-aged alloy with 0.5 wt%Zn addition,whose yield strength,ultimate tensile strength and elongation are 179 MPa,301 MPa and 5.3%,respectively.

关键词： Mg-Nd-Gd alloy Zn addition Competitive precipitation behavior Microstructural characterization