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稀有金属材料与工程 2009年第A3期38卷 83-87页

作者： Li Zhenliang xie jianxin Chen Wei Zhai Jing Ren Huiping Wang Yufeng University of Science and Technology Beijing Beijing 100083 China Ningbo Branch of China Academy of Ordnance Science Ningbo 315103 China Inner Mongolia University of Science and Technology Baotou 014010 China

Ultrahigh strength Al-12Zn-2.4Mg-1.1Cu-0.20Zr-0.30Sc-0.30Ni alloy billets were fabricated by spray deposition method(the Osprey process). The effect of homogenization treatment on the microstructures and tensile properties were investigated by OM, SEM and EDS. The results show that adding small amount of Sc and Zr can greatly refine the grain size of the billet, with the average grain size of 10 μm. Grain-boundary becomes coarser firstly and then thinner under different homogenizing condition and grain coarsening were observed. The solute elements content of Zn inside grains has a peak at 490 ℃ /2 h, and Cu element, which was solved into matrix, can enhance the matrix hardness obviously during homogenization. The suitable homogenizing treatment is 460～490 °C/2 h for the hot extrusion of the studied alloy; after the optimized solid solution and T6 aging, the highest ultimate tensile strength (UTS) is 858 MPa with a ductility of 4.8%.

关键词：喷射沉积方法晶粒合金热挤压

机器学习辅助2000MPa级弹簧钢成分和热处理工艺开发

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金属学报 2023年第11期59卷 1499-1512页

作者：杨累赵帆姜磊谢建新北京科技大学新材料技术研究院现代交通金属材料与加工技术北京实验室北京100083 北京科技大学新材料技术研究院材料先进制备技术教育部重点实验室北京100083 东北轻合金有限责任公司哈尔滨150060 北京科技大学新材料技术研究院北京材料基因工程高精尖创新中心北京100083

通过收集弹簧钢及其他典型淬火+回火型钢铁材料的文献数据,采用面向性能的机器学习设计系统(MLDS)结合实验优化,实现了具备超高强度和良好塑性的新型弹簧钢化学成分及热处理工艺参数的快速设计。所开发的2种新型弹簧钢的抗拉强度分别为2... 详细信息

通过收集弹簧钢及其他典型淬火+回火型钢铁材料的文献数据,采用面向性能的机器学习设计系统(MLDS)结合实验优化,实现了具备超高强度和良好塑性的新型弹簧钢化学成分及热处理工艺参数的快速设计。所开发的2种新型弹簧钢的抗拉强度分别为2183.5和2193.0 MPa、屈服强度分别为1923.0和2024.5 MPa、断后伸长率分别为10.5%和9.7%、断面收缩率分别为42.4%和41.5%。新型弹簧钢的强化方式以晶界强化和位错强化为主,细小的晶粒尺寸和适量的奥氏体使得弹簧钢在具备超高强度的同时保持良好的塑性。与现有同等强度级别的超高强度钢相比,新型弹簧钢具有显著的成本优势和工艺优势。

关键词：弹簧钢超高强热处理机器学习

Research on Dieless Drawing Process of Stainless Steel Tapered Tube

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Research on Dieless Drawing Process of Stainless Steel Taper...

Preparation and Characterization of Carbon Nanotubes-Coated Cordierite for Catalyst Supports

中国材料大会2012

作者： Xuefeng Liu Ye Zhang Fang Qin Haoen Mao jianxin xie Key Laboratory for Advanced Materials Processing(MOE) University of Science and Technology Beijing Schaeffler Trading(Shanghai)Corporation Limited School of Materials Science and Engineering Hebei University of Science and Technology

ISBN: (纸本)9783037856093

The traditional forming technologies of stainless steel tapered tube have some disadvantages,such as its complicated processes,few product specification,low production efficiency and high production cost.Dieless drawing is a new kind of near net-shaping process for fabricating tapered metallic tubes with large deformation per pass,high yield ratio of material and flexible production.Dieless drawing of stainless steel tapered tube was studied systematically in order to establish both temperature field model with respect to the changes of boundary condition and metal flow velocity during deformation,and a drawing speed controlling model with respect to the volume change of deformation zone.The models were verified by experiments in the present investigation.Finally,a continuous pickling process with variable-speed was proposed for tapered metallic tube,which was successfully applied to surface oxidation film removal of the stainless steel tapered tube.

关键词： Tapered tube Stainless steel Forming technology Dieless drawing

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Journal of Natural Gas Chemistry 2006年第3期15卷 211-216页

作者： Jianmei Wang Rong Wang Xiujin Yu jianxin Lin Feng xie Kemei Wei National Engineering Research Center of Chemical Fertilizer Catalyst Fuzhou University Fuzhou 350002 China

The carbon nanotubes-coated cordierite （CNTs-cordierite） was fabricated by pyrolysis of ethine on cordierite with iron catalyst, which was penetrated into the cordierite substrate by vacuum impregnation. The cordierite substrate, carbon naontubes, and CNTs-cordierite were characterized by SEM, TEM/HREM, BET, and TGA. The results show that the carbon nanotubes were distributed uniformly on the surface of cordierite. A significant increase in BET surface area and pore volume was observed, and a suitable pore-size distribution was obtained. On the CNTs-cordierite, carbon nanotubes penetrated into the cordierite substrate, which led to a remarkable stability of the CNTs against ultrasound maltreatment. Growth time is an important factor for thermostability and texture of the sample. The mass increased but the purity decreased with the growth time, which caused the exothermic peak shift to low temperature, and the corresponding full width half maximum （FWHM） of the peak in DTG increased.

关键词： carbon nanotube cordierite pyrolysis ethine catalyst support

Numerical Simulation of Dieless Drawing Process with Non-steady Processing Parameters

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稀有金属材料与工程 2011年第S3期40卷 179-184页

作者： He Yong, Liu Xuefeng, Wang Zhen, xie jianxin University of Science and Technology Beijing, Beijing 100083, China Univ Sci & Technol Beijing Key Lab Adv Proc Technol Mat Minist Educ Beijing 100083 Peoples R China

Since processing parameters have always been assumed to be stable in the current finite element numerical simulation of dieless drawing process, the simulation results for the product dimension tend to stabilize gradually. In fact, the dimension fluctuation exists in the forming process all the while. A mathematical model of Gauss distribution for processing parameters was employed and a finite element numerical model of dieless drawing process with non-steady processing parameters was established. Dieless drawing processing of Ni-Ti alloy wire was conducted for verifying the proposed model. The results indicated that the non-steady processing parameters model had higher simulation accuracy of the wire diameter than that given by the steady parameters model. Furthermore, the model could also be used to analyze the fluctuation characteristics in the whole dieless drawing process.

关键词： dieless drawing non-steady processing parameter thermal-mechanical coupling finite element numerical simulation Gauss distribution

SEM in-situ Fatigue Observation on Crack Initiation and Growth from Inclusion in P/M Rene95 Superalloy

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Journal of University of Science and Technology Beijing 2001年第3期8卷 195-197页

作者： Lina Zhang, jianxin Dong, Xishan xie Material Science and Engineering School, University of Science and Technology Beijing, Beijing 100083, China Material Science and Eng. Sch. Univ. of Sci. and Technol. Beijing Beijing 100083 China

A special designed experiment was conducted for observing crack initiation and growth in P/M Rene95 superalloy under tension-tension loading by self-made SEM in-situ fatigue loading stag. Several alumina inclusion particles exposed at the specimen surface were observed carefully. During fatigue test inclusions led to cracks initiation. The cracks can be formed by two mechanisms. Generally, the cracks nucleated at the interface between inclusion and matrix. Sometimes, cracks were also formed inside the inclusion. As the increase of cycles, some cracks at the interface between inclusion and matrix broadened and propagated along the direction about 45 degrees to the loading axis. On the other hand, the cracks inside the inclusion propagated in the inclusion and towards matrix.

关键词： inclusion P/M superalloy LCF SEM in-situ fatigue

Efficient and selective H_(2)O_(2)production through uranyl-assisted photocatalytic oxygen reduction reaction process in a uranium-organic framework

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Science China Chemistry 2024年第7期67卷 2274-2281页

作者： jianxin Song Chao Liang Baoyu Li Xuemin Wang Min Lei Lisha Jiang Zhenyu Li Yugang Zhang Jian xie Zuju Ma Xing Dai Yanlong Wang Shuao Wang Wei Liu School of Environmental and Materials Engineering Yantai UniversityYantai 264005China State Key Laboratory of Radiation Medicine and Protection School for Radiological and Interdisciplinary Sciences(RAD-X)and Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education InstitutionsSoochow UniversitySuzhou 215123China School of Life and Environmental Sciences Shaoxing UniversityShaoxing 312000China School of Nuclear Science and Technology Xi’an Jiaotong UniversityXi’an 710049China

Harnessing solar energy by photocatalytically converting oxygen and water into high-value-added H_(2)O_(2)is a promising way of alleviating both environmental and energy issues.It is worth noting that suppressing detrimental side reactions,such as the generation of·O_(2)^(-),is a critical approach to enhancing H_(2)O_(2)production.Herein,a 2-fold interpenetrating 3D uranium-organic framework(YTU-W-1)was developed and introduced for photocatalytic H_(2)O_(2)production.The material demonstrates a different photocatalytic mechanism when employing uranyl as an initiator,as compared with the conventional semiconductor photocatalytic pathway involving photo-generated charge carriers.Benefiting from the strong hydrogen abstraction effect of the U≡O·and the direct one-step oxygen reduction pathway,YTU-W-1 exhibits enhanced photocatalytic performance for H_(2)O_(2)production with yield efficiency of 221μmol h-1g-1.Furthermore,YTU-W-1 displays a high H_(2)O_(2)selectivity of 68%,confirmed by rotating ring-disk electrode(RRDE)measurement.DFTcalculations were used to elucidate the critical role of uranyl in the photocatalytic oxygen reduction reaction for H_(2)O_(2)production.This research introduces an innovative approach to photo-driven H_(2)O_(2)production,underscoring the potential for heterogeneous catalysts to engage in photocatalytic reactions independently of photogenerated charge carriers.

关键词： uranyl metal-organic frameworks oxygen reduction reaction photocatalytic H_(2)O_(2)synthesis

机器学习辅助高性能银合金电接触材料的快速发现

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金属学报 2022年第6期58卷 816-826页

作者：何兴群付华栋张洪涛方继恒谢明谢建新北京科技大学北京材料基因工程高精尖创新中心北京100083 北京科技大学现代交通金属材料与加工技术北京实验室北京100083 北京科技大学材料先进制备技术教育部重点实验室北京100083 昆明贵金属研究所稀贵金属综合利用新技术国家重点实验室昆明650106

为了快速发现高性能银合金电接触材料,从文献中收集了32组铸造法制备的银合金电接触材料的成分和性能数据,采用特征量筛选方法识别出影响合金性能的关键合金因子,采用支持向量机算法建立了合金导电率和硬度预测模型,实现了合金成分的快... 详细信息

为了快速发现高性能银合金电接触材料,从文献中收集了32组铸造法制备的银合金电接触材料的成分和性能数据,采用特征量筛选方法识别出影响合金性能的关键合金因子,采用支持向量机算法建立了合金导电率和硬度预测模型,实现了合金成分的快速设计。选取预测性能优异的Ag-19.53Cu-1.36Ni、Ag-10.20Cu-0.20Ni-0.05Ce和Ag-11.43Cu-0.66Ni-0.05Ce (质量分数,%) 3种成分设计方案进行工业生产条件的实验验证,性能预测结果与实验结果误差均小于10%,3种合金导电率均≥79%IACS,Vickers硬度均≥87 HV,综合性能均优于已有铸造法制备的银合金电接触材料。上述研究结果表明,本工作建立的机器学习成分设计方法可靠性好,有助于提高合金成分设计效率,快速发现综合性能优异的银合金电接触材料。

关键词：机器学习银合金电接触材料成分设计

Investigation of Sintering Technology for Composite of Stainless Steel and Partially Stabilized Zirconia

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Journal of Materials Science & Technology 2002年第1期18卷 10-12页

作者： Wenquan ZHANG, jianxin xie, Changjing ZHANG and Zhiguo YANGSchool of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China [ Manuscript received September 4, 2000, in revised form April 13, 2001] Sch. of Mat. Sci. and Eng. Univ. of Sci. and Technol. Beijing Beijing 100083 China

The sintering technology for mixed powdered extrusion rods of different proportions of stainless steel to magnesia partially stabilized zirconia (PSZ) was investigated. The effects of some sintering parameters including holding time, atmosphere and protective gas pressure on shrinkage, relative density, microstructure, micro-Vickers hardness and compression strength of sintered samples were mainly researched. The experimental results are as follows: (1) The shrinkage and the relative density of the sintered samples decrease as increasing stainless steel content in the composite, except for the case containing 90 percent of stainless steel; (2) The porosity in PSZ matrix rises as increasing the stainless steel content in the composite; (3) Longer sintering holding time, higher sintering vacuum and gas-pressure sintering process not only enhance the relative density, but also improve microstructure of composite; (4) Micro-Vickers hardness of PSZ matrix decreases as increasing stainless steel content, while that of stainless steel particles in sintered samples varies unnoticeably.

关键词： PSZ Stainless steel Composite Sintering technology

冷轧变形对高性能Cu-Ni-Si合金组织性能与析出行为的影响

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金属学报 2023年第5期59卷 585-598页

作者：王长胜付华栋张洪涛谢建新北京科技大学、北京材料基因工程高精尖创新中心北京100083 北京科技大学现代交通金属材料与加工技术北京实验室北京100083 北京科技大学材料先进制备技术教育部重点实验室北京100083

采用DSC、TEM、导电率和力学性能等测试方法,研究了不同冷轧变形量对Cu-3.0Ni-0.60Si-0.16Zn-0.15Cr-0.03P(质量分数,%)合金组织性能与析出行为的影响,旨在通过工艺调控提升该合金的综合性能。通过对比不同冷轧变形后合金的开始析出温... 详细信息

采用DSC、TEM、导电率和力学性能等测试方法,研究了不同冷轧变形量对Cu-3.0Ni-0.60Si-0.16Zn-0.15Cr-0.03P(质量分数,%)合金组织性能与析出行为的影响,旨在通过工艺调控提升该合金的综合性能。通过对比不同冷轧变形后合金的开始析出温度和再结晶温度以及时效后合金的组织性能,确定了高性能Cu-NiSi系合金的形变-时效工艺参数,明确了冷轧变形量对合金时效析出动力学的影响规律和强化相析出的调控机制;合金经过95%冷轧+450℃、60 min形变热处理后获得了显著优于现有Cu-Ni-Si合金(如C70250)的性能,其抗拉强度为(841±10)MPa,导电率为(52.2±0.3)%IACS。

关键词：冷轧变形时效析出微观组织析出动力学