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Influences of the Texture Characteristic and Interdendritic LPSO Phase Distribution on the Tensile Properties of Mg–Gd–Y–Zn–Zr Sheets Through Hot Rolling

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Acta Metallurgica Sinica(English Letters) 2021年第8期34卷 1051-1064页

作者： Bing Li Ji Wu bugang teng School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China National Key Laboratory for Precision Hot Processing of Metals Harbin Institute of TechnologyHarbin 150001China

The Mg–Gd–Y–Zn–Zr alloy sheets with different texture characteristics and distribution of the interdendritic long periodstacking ordered(LPSO) phases were fabricated through altering the final rolling reduction(FRR). The results showed that the texture characteristic was closely related to FRR and affected the tensile properties of the resulted sheets to some extent. The Schmid factor(SF) of the basal 〈a〉 slip improved with further FRR, which was ascribed to that the dynamic recrystallization(DRX) grains expand into the deformed grains with basal texture. However, the improvement of the tensile yield strength(TYS) with further FRR indicates that the strengthening effect from DRX grains surpasses the weakening effect from the elevated SF. The formation of the line-distributed interdendritic 14 H-LPSO phases can also affect the tensile properties of the resulted sheets. The line-distributed interdendritic 14 H-LPSO phases along rolling direction(RD) can act as reinforcing fiber and contribute to the higher TYS along RD and 45° to some extent, which resulted in the higher TYS along 45° compared with that along transverse direction(TD) for each resulted sheet under the circumstance of approximate basal 〈a〉 and pyramid 〈c + a〉 friction stress. Thus, the tensile yield strength is not only related to the texture, but also depends on the grain size and line-distributed interdendritic LPSO phases. The micro-cracks spread perpendicular to the tension direction, and thus, the larger cracks form within the line-distributed 14 H-LPSO phases during tension along TD, which accounts for the lower fracture elongation along TD.

关键词： Final rolling reduction Texture characteristic Interdendritic 14H-LPSO phases distribution Tensile property

Solid state recycling of Mg-Gd-Y-Zn-Zr alloy chips by spark plasma

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Journal of Magnesium and Alloys 2020年第4期8卷 1154-1165页

作者： Bing Li bugang teng Ziqing Zhu School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China National Key Laboratory for Precision Hot Processing of Metals Harbin Institute of TechnologyHarbin 150001China

The consolidation Mg-Gd-Y-Zn-Zr billets containing long period-stacking ordered(LPSO)phase were recycled from the metal chips through the spark plasma sintering(SPS)process,which achieves the effective metallurgical bonding between metal *** effects of the sintering parameters on the microstructure characteristic and mechanical properties of the recycled billets were *** metal chips were effectively bonded in the recycled billets sintered at 500°C,however,the metal chips partly melted into semi-solid state as sintering temperature increased to 550°*** oxidation films of rare earth(RE)element formed at the bond interface between metal chips during SPS recycling *** consolidation recycled billets through SPS demonstrated the rival compression failure strain and superior compression stress compared with the referenced cast *** lamellar 14H-LPSO phases hardly precipitate in the vicinity of the bond interface between metal chips after heat treatment with air ***,the furnace cooling facilitates the precipitation of 14H-LPSO phases within the a-Mg grains,even the a-Mg matrix adjacent to the bond *** oxide films at the bond interface between the metal chips were zigzagged and fragmented during the isothermal *** cracks or holes were hardly observed adjacent to the bond interface during isothermal compression,which reveals superior bond properties and deformation consistency performance between metal chips.c 2020 Published by Elsevier *** behalf of Chongqing University.

关键词： Solid state recycling Spark plasma sintering Heat treatment Bond interface.

Solid state recycling of Mg-Gd-Y-Zn-Zr alloy chips by isothermal sintering and equal channel angular pressing

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Journal of Magnesium and Alloys 2024年第7期12卷 2725-2740页

作者： Yanbo Pei Hongjun Ma Meng Yuan bugang teng School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China National Key Laboratory for Precision Hot Processing of Metals Harbin Institute of TechnologyHarbin 150001China

The Mg-7Gd-4Y-2Zn-0.5Zr alloy chips were successfully recycled through isothermal sintering and equal channel angular pressing(ECAP).The mechanical properties and microstructure evolution of samples during the recycling process were studied in *** eutectic phases in the as-cast alloy transform into long period-stacking ordered(LPSO)phases after homogenization,which can improve the plasticity of the *** isothermal sintering,the density of the sample is lower than that of the homogenized sample,and oxide films are formed adjacent to the bonding interface of the metal ***,the plasticity of the sintered sample is *** samples are fabricated after *** the grains are not refined compared to the sintered sample,the microstructure becomes more uniform due to *** interdendritic LPSO phase and kinked 14H-LPSO phase are formed in the alloy due to the shear deformation during the ECAP process,which improves the strength and plasticity of the sample ***,the basal texture is weakened due to the Bc route of the ECAP process,which can increase the Schmid factor of the basal slip system and improve the elongation of the *** 2 ECAP passes,the fully densified recycled billet shows superior mechanical properties with an ultimate tensile strength of 307.1 MPa and elongation of 11.1%.

关键词： Mg-Gd-Y-Zn-Zr alloy Solid state recycling Microstructure evolution LPSO phase Equal channel angular pressing

Texture evolution prediction of 2219 aluminum alloy sheet under hydro-bulging using cross-scale numerical modeling

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Journal of Materials Science & Technology 2023年第18期149卷 190-204页

作者： Yanbo Pei Yonggang Hao Jie Zhao Jiantong Yang bugang teng School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China National Key Laboratory for Precision Hot Processing of Metals Harbin Institute of TechnologyHarbin 150001China Department of Materials Science and Engineering China University of Mining&Technology(Beijing)Beijing 100083China

A simultaneous prediction of macroscopic deformation and microstructure evolution is critical for un-derstanding the deformation mechanism of *** this work,the hydro-bulging process of 2219 aluminum alloy sheet was investigated using cross-scale numerical modeling,in which the macroscopic finite element method(FEM)and crystal plasticity finite element method(CPFEM)were *** calculated texture evolution exhibits good agreement with the experimental results,and the stress er-ror between the two scales is generally *** effects of different strain states on texture evolution and slip mode are further *** the strain ratioηincreases,the volume fractions of the initial Rotated Copper texture component andγ-Fiber texture component decrease significantly,which tend to be stabilized at P texture *** initial Rotated Cube texture component is inclined to rotate towards the Cube texture component,while the volume fraction of this orientation is relatively *** lower strain ratio can considerably enhance the activity of more equivalent slip systems,promoting a more uniform strain distribution over *** difficulty of grain deformation changes as the lat-tice *** grain with easy-to-deform orientation can gradually rotate to a stable orientation during plastic deformation,which has a lower Schmid factor.

关键词： Cross-scale modeling Crystal plasticity Texture evolution Aluminum alloy Hydro-bulging forming

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内高压成形矩形断面圆角应力分析

机械工程学报 2006年第6期42卷 150-155页

作者：刘钢苑世剑滕步刚哈尔滨工业大学材料科学与工程学院哈尔滨150001

采用力学分析和数值模拟方法对圆角部位在内高压成形过程中的应力分布和变形机理进行分析,揭示出圆角和直边过渡区的减薄以及开裂的力学机理。提出内高压成形中圆角和直边的过渡区材料最易满足塑性屈服条件, 并发生厚度方向的压缩应变,... 详细信息

采用力学分析和数值模拟方法对圆角部位在内高压成形过程中的应力分布和变形机理进行分析,揭示出圆角和直边过渡区的减薄以及开裂的力学机理。提出内高压成形中圆角和直边的过渡区材料最易满足塑性屈服条件, 并发生厚度方向的压缩应变,因此在过渡区易发生剧烈的减薄变形;并且当管材壁厚与圆角半径的比值大于0．5 时,直边区和圆角区的屈服条件差别较大,引起变形不均匀性增大,更易导致过渡区的过度减薄和开裂。分析结果有助于指导内高压成形零件设计和工艺设计,改善矩形断面零件内高压成形件产品质量。

关键词：内高压成形过渡圆角成形轻量化构件局部减薄开裂

Analysis of abnormal texture formation and strengthening mechanism in an extruded Mg-Gd-Y-Zn-Zr alloy

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Journal of Materials Science & Technology 2020年第10期42卷 133-145页

作者： Xueze Jin Wenchen Xu Zhongze Yang Can Yuan Debin Shan bugangteng Bo Cheng Jin National Key Laboratory for Precision Hot Processing of Metals&School of Materials Science and Engineering Harbin Institute of TechnologyHarbin150001China Advanced Composites Simulation Lab University of Southern CaliforniaLos AngelesCA 90089-0241USA

A Mg-Gd-Y-Zn-Zr magnesium alloy with different initial states was extruded under different extrusion *** effect of solution treatment and extrusion parameters on the microstructure,texture and mechanical properties were analyzed in detail,and the abnormal texture formation and strengthening mechanism was *** extruded at low temperature and small extrusion ratio,the bimodal microstructure consisting of fine dynamically recrystallized grains and coarse deformed grains occurred both in the as-cast alloy and solution-treated *** the extrusion temperature and extrusion ratio were increased,the amount and size of dynamically recrystallized grains increased and the grain size of the solution-treated alloy showed higher growth ***,an abnormal texture withparallel with extrusion direction developed due to the occurrence of non-basal slip and continuous dynamic *** could be enhanced by solution treatment,high temperature,and large extrusion *** the as-cast alloy and solution-treated alloy exhibited the highest tensile strength after extrusion at 300℃with an extrusion ratio of *** refinement was the main strengthening mechanism utilized in both the as-cast alloy and the solution-treated *** hardening played an important role in the sample extruded at low temperature and small extrusion ratio,with the highest contribution of about 33 MPa after extrusion at 300℃with an extrusion ratio of *** strengthening contributed more in the sample extruded at high temperature and large extrusion ratio,but no more than 24.1 *** strengthening was another strengthening mechanism in the extruded as-cast alloy,especially at high temperature and large extrusion ratio(no more than 9 MPa).

关键词： Hot extrusion Heat treatment Abnormal texture Strengthening mechanism Quantitative analysis

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大型密封法兰弯曲成形工艺研究

中国机械工程 2006年第19期17卷 2046-2048,2052页

作者：滕步刚苑世剑王仲仁刘元君哈尔滨工业大学哈尔滨150001

提出了一种大型密封法兰成形新工艺,包括分段弯曲、现场组焊、现场精加工。新工艺免去了大型立车的粗加工,取而代之的是分段弯曲成形工艺,最后在施工现场进行组焊并采用多功能机床进行精加工。通过小型模拟件的实验与数值模拟研究,分析... 详细信息

提出了一种大型密封法兰成形新工艺,包括分段弯曲、现场组焊、现场精加工。新工艺免去了大型立车的粗加工,取而代之的是分段弯曲成形工艺,最后在施工现场进行组焊并采用多功能机床进行精加工。通过小型模拟件的实验与数值模拟研究,分析了L形非对称截面法兰弯曲成形过程中工件的变形规律,以及弯曲成形后工件的截面形状变化和侧弯情况,并采用L形非对称截面法兰成对弯曲的方法,使其截面形式成为对称结构,从而有效地解决了非对称截面法兰单件弯曲存在的侧弯缺陷。采用新工艺制造了某风洞工程上直径为8·5m的大型密封法兰,实践表明,采用新工艺成形大型法兰是完全可行的,其加工制造精度完全满足设计要求。由于新工艺不需立车,为特大直径法兰的制造开辟了新途径。

关键词：大型密封法兰弯曲多功能机床现场精加工

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薄壁Y型三通管内高压成形起皱与开裂分析

材料科学与工艺 2017年第4期25卷 11-16页

作者：彭俊阳罗德高滕步刚刘钢哈尔滨工业大学材料科学与工程学院哈尔滨150001 中国商飞北京民用飞机技术研究中心民用飞机结构与复合材料北京市重点实验室北京102211

本文针对薄壁Y型三通管在内高压成形过程中产生起皱、开裂缺陷的问题进行了相关研究.首先通过实验确定了Y型三通管在成形过程中产生典型缺陷的位置及类型;其次利用有限元方法分析了补料比对应力状态分区和典型点应力轨迹的影响;最后建... 详细信息

本文针对薄壁Y型三通管在内高压成形过程中产生起皱、开裂缺陷的问题进行了相关研究.首先通过实验确定了Y型三通管在成形过程中产生典型缺陷的位置及类型;其次利用有限元方法分析了补料比对应力状态分区和典型点应力轨迹的影响;最后建立了加载路径的"内压-轴向补料"成形窗口.研究表明:补料比对应力状态有显著影响,通过调整补料比来改变应力状态,是避免起皱的有效措施.此外,本研究给出了不同实验结果在成形窗口中的对应位置,当加载路径超出成形区时,三通管件就会产生起皱或破裂的缺陷,甚至两种缺陷会依次发生.

关键词：内高压成形 Y型三通管起皱开裂补料量

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特大环形件成形与制造技术

金属加工（热加工） 2008年第23期 42-44,46页

作者：滕步刚苑世剑哈尔滨工业大学金属精密热加工国家级重点实验室黑龙江150001

提出了一种大型环形件成形制造新技术,即采用分段弯曲、现场组焊、现场精加工的方法制作大型环形件。新技术免去了大型立车的粗加工,取而代之的是分段弯曲成形工艺,最后在施工现场进行组焊并采用多功能机床进行精加工。研究了矩形截面... 详细信息

提出了一种大型环形件成形制造新技术,即采用分段弯曲、现场组焊、现场精加工的方法制作大型环形件。新技术免去了大型立车的粗加工,取而代之的是分段弯曲成形工艺,最后在施工现场进行组焊并采用多功能机床进行精加工。研究了矩形截面和复杂截面环形件弯曲变形规律,提出了控制非对称截面环形件弯曲时产生侧弯的成对弯曲措施。该技术成功应用于某空间环境模拟器φ9m及某风洞中φ8.5m大型法兰的成形,并采用多功能机床实现了环形法兰的现场精加工,加工精度完全满足设计要求。由于此法不需立车,从而为特大直径环形件的制造开辟了新途径。

关键词：弯曲成形工艺制造技术环形件空间环境模拟器多功能机床现场组焊大型法兰非对称截面