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MICROSTRUCTURE AND TENSILE PROPERTY OF AN AS-CAST DUPLEX STAINLESS STEEL

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Acta Metallurgica Sinica(English Letters) 2001年第4期14卷 285-290页

作者： P.L. Mao1,2), K. Yang1) and C. Y. Su1) 1) institute of Metal Research, The Chinese Academy of Sciences, shengyang 110016, china 2) School of Metal Material, shenyang University of technology, shengyang 110023, china institute of Metal Research The Chinese Academy of Sciences School of Metal Material Shenyang University of Technology

The effect of high temperature solution heat treatment on the microstructure and tensile property of as-cast 0Cr17Mnl4Mo2N duplex stainless steel was investigated. It was found that the morphology of δ-ferrite in the dual phases microstructures changed gradually from dendritic to lamellar and then to spheroidal, and its distribution became more uniform under appropriate treatment. When the treat temperature was lower than 1250°C, the spheroidal ratio and the homogeneous distribution of δ-ferrite increased with the increase of temperature, which corresponds to a better tensile property. In addition, when the treat temperature reached 1250°C and above, the microstructure consists of coarse equiaxial δ-ferrite grains with the needle austenite at its boundaries, which results in the decrease of the tensile properties of the steel.

关键词： Mechanical properties Metal castings Microstructure Tensile properties

ENVIRONMENTAL DAMAGE OF CAST Ni-BASE SUPERALLOY K17

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Acta Metallurgica Sinica(English Letters) 1989年第1期2卷 51-56页

作者： GUO Jianting HUANG Rongfang institute of Metal Research,Academia Sinica,shenyang,chinaYANG Hongcai MA Jun Northeast University of technology,shenyang,china GUO Jianting,Associate Professor,institute of Metal Research,Academia Sinica,shengyang,china

Rupture and tensile properties of K17 before and after thermal exposure in vacuum,air and hot corrosion environments have been *** results show that vacuum exposure es- sentially does not affect the rupture lives but it results in the decrease of high temperature ten- sile strength and increases of rupture and high temperature tensile ductilities;air or hot corro- sion environmental exposure results in the degradation of alloy:severely reduce the rupture and high temperature tensile properties,hot corrosion environmental exposure being more *** former causes grain boundary oxidation and depletion of Cr,and the later makes the sulphurization at grain *** results in the concentration of S and de- pletion of Cr at grain boundaries and,consequently,weakens the grain boundaries.

关键词： K17 alloy environmental demage hot corrosion grain boundary oxidation depletion of Cr

The genesis and resource potential of gold deposits in the liaodong Peninsula

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Science china Earth Sciences 2024年第3期67卷 657-672页

作者： Rixiang ZHU Jin-Hui YANG Gongwen WANG Qingdong ZENG Guoqiang XUE Tao XU Xinghui li Peng ZHANG Da LEI Guang ZHU State Key Laboratory of lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China School of Earth Sciences and Resources China University of GeosciencesBeijing 100083China shenyang Center China Geological SurveyShenyang 110034China School of Resources and Environmental Engineering Hefei University of TechnologyHefei 230009China

Plenty of gold deposits related to Late Mesozoic craton destruction are widely distributed in eastern North china Craton. However, significant differences in research degrees, ore-forming characteristics, and proven reserves exist among different regions in the North china Craton. The liaodong Peninsula has similar regional geological characteristics to those of the Jiaodong Peninsula, with both experiencing craton destruction during Late Mesozoic, but the two areas have substantial differences in terms of gold mineralization and the proven gold resources. Based on regional geology, Mesozoic magmatictectonic evolution and ore geology, combined with integrated geophysical exploration and big data AI resource prediction, in this paper, we propose that the ore-forming materials of Late Mesozoic gold deposits in liaodong were mainly originated from mantle-derived melts and/or fluids induced by craton destruction. The gold deposits were primarily controlled by NE-NNEtrending faults, mainly classified as fracture-controlled altered rock-type and sulfide-bearing quartz vein-type. Moreover, our study predicts that the Yalu River fault zone and its related secondary faults, as well as the periphery and deeper parts of known goldfields, are the important regions for future gold resource exploration. The Yalu River metallogenic belt has an enormous potential for gold resources, and the liaodong Peninsula has a potential to add thousands of tons of gold resources.

关键词： liaodong Peninsula gold deposit Integrated geophysical exploration Prospecting potential Direction for prospecting breakthroughs

Highly sensitive nanozyme strip:An effective tool for forensic material evidence identification

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Nano Research 2024年第3期17卷 1785-1791页

作者： Juanji Hong Zhanjun Guo Dihan Duan Yi Zhang Xin Chen Yongjiu li Zheng Tu Lei Feng Lei Chen Xiyun Yan lizeng Gao Minmin liang Demin Duan Experimental Center of Advanced Materials School of Materials Science&EngineeringBeijing Institute of TechnologyBeijing 100081China College of Bioscience and Biotechnology Shenyang Agricultural UniversityShenyang 110866China Chongqing kangjuquanhong biology science and technology Co. ltdChongqing 400026China Key Laboratory of Forensic Genetics Institute of Forensic ScienceMinistry of Public SecurityBeijing 100038China CAS Engineering Laboratory for Nanozyme Key Laboratory of BiomacromoleculesInstitute of BiophysicsChinese Academic of ScienceBeijing 100101China

During criminal case investigations,blood evidence tracing is critical for criminal ***,the blood stains are often cleaned or covered up after the crime,resulting in trace residue and difficult ***,a highly sensitive and specific method for the rapid detection of human blood stains remains *** solve this problem,we established a nanozyme-based strip for rapid detection of blood evidence with high sensitivity and *** construct reliable nanozyme strips,we synthesized CoFe_(2)O_(4) nanozymes with high peroxidase-like activity by scaling up to gram level,which can be supplied for six million tests,and conjugated antibody as a detection probe in nanozyme *** developed CoFe_(2)O_(4) nanozyme strip can detect human hemoglobin(HGB)at a concentration as low as 1 ng/mL,which is 100 times lower than the commercially available colloidal gold strips(100 ng/mL).Moreover,this CoFe_(2)O_(4) nanozyme strip showed high generality on 12 substrates and high specificity to human HGB among 13 animal blood ***,we applied the developed CoFe_(2)O_(4) nanozyme strip to successfully detect blood stains in three real cases,where the current commercial colloidal gold strip failed to *** results suggest that the CoFe_(2)O_(4) nanozyme strip can be used as an effective on-scene detection method for human blood stains,and can further be used as a long-term preserved material evidence for traceability inquiry.

关键词： CoFe_(2)O_(4)nanozyme nanozyme strip peroxidase-like activity human hemoglobin blood evidence

Mechanical Properties and Oxidation Behaviors of Self-Healing SiCf/SiC-SiBCN Composites Exposed to H_(2)O/O_(2)/Na_(2)SO_(4)Environments

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Acta Metallurgica Sinica(English Letters) 2023年第11期36卷 1909-1923页

作者： Suya Ji Bin liang Chenglong Hu shengyang Pang Rida Zhao Jian li Sufang Tang Shi-Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang110016China

The oxidation behaviors and their influence on the mechanical properties of self-healing SiCf/SiC-SiBCN composites were investigated in H_(2)O/O_(2)and H_(2)O/O_(2)/Na_(2)SO_(4)environments at 1200‒1350℃for 100 *** the temperatures increase from 1200 to 1350℃,the oxidation rate constants increase from 0.45×10^(–7)to 1.58×10^(–7)mg^(2)/(mm^(4) h)in H_(2)O/O_(2),and from 1.02×10^(–7)to 3.42×10^(–7)mg^(2)/(mm^(4) h)in H_(2)O/O_(2)/Na_(2)SO_(4).The involvement of Na_(2)SO_(4)leads to the formation of a loose lamellar oxide layer,the breakage of the SiBCN/CVI-SiC interface and the decrease in the oxide viscosity,thus accelerating the oxidation of the *** composites show the maximum retention rate of strength(102%,535.71 MPa)after oxidation in H_(2)O/O_(2)at 1200℃due to the good self-healing capacity of the produced glass,while the minimum(82%,430.56 MPa)in H_(2)O/O_(2)/Na_(2)SO_(4)at 1350℃caused by the severe microstructural corrosion derived from Na_(2)SO_(4).

关键词： SiCf/SiC-SiBCN composite Mechanical property Oxidation Chemical vapor infiltration and polymer infiltration and pyrolysis(CVI-PIP) Self-healing

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C/SiC-BN复合材料的制备及氧化行为

无机材料学报 2024年第7期39卷 779-786页

作者：姜灵毅庞生洋杨超张悦胡成龙汤素芳沈阳工业大学材料科学与工程学院沈阳110870 中国科学院金属研究所沈阳110016

C/SiC复合材料作为一种高温结构材料,在航空航天热防护领域具有广泛的应用前景。然而,该材料的中低温抗氧化性能相对较差,制约了其在更广泛领域的应用。本研究采用料浆抽滤工艺,通过调节料浆中陶瓷含量在纤维增强体中引入不同含量的抗... 详细信息

C/SiC复合材料作为一种高温结构材料,在航空航天热防护领域具有广泛的应用前景。然而,该材料的中低温抗氧化性能相对较差,制约了其在更广泛领域的应用。本研究采用料浆抽滤工艺,通过调节料浆中陶瓷含量在纤维增强体中引入不同含量的抗氧化组元BN,再通过反应熔体渗透法制备C/SiC-BN复合材料。系统研究了不同BN含量对复合材料结构组成及抗氧化行为的影响,并分析相关氧化机理。研究结果表明:引入BN颗粒显著降低了C/SiC的开口孔隙率,并明显提高了C/SiC的起始氧化温度。引入质量分数3%BN时,C/SiC-BN复合材料(B3样品)的抗氧化性能最优,其在900、1200和1500℃静态氧化1 h的质量损失率分别为0.009%、–0.301%、–0.596%,显著优于C/SiC。1500℃氧化后,B3样品的强度保持率最高,达到52%。900℃氧化时,C/SiC-BN复合材料主要经历C相和BN相的氧化,以O_(2)扩散反应控制的缓慢失重为主;1200℃氧化时,C相和BN相氧化速率加快,SiC发显著氧化,生成的B_(2)O_(3)、硼硅酸盐和SiO_(2)等氧化产物减缓了O_(2)的扩散速率,减小了基体碳的损伤;1500℃氧化时,SiC氧化速率加快,生成的SiO_(2)在复合材料表面形成的连续氧化膜阻碍了O_(2)的向内扩散。B_(2)O_(3)、CO等气体产物溢出及持续生成SiO_(2)主导了整个氧化过程。

关键词：料浆浸渍 C/SiC BN 微观结构氧化行为

Deposition kinetics and mechanism of pyrocarbon for electromagnetic-coupling chemical vapor infiltration process

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Journal of Materials Science & technology 2022年第6期101卷 118-127页

作者： Chenglong Hu Rida Zhao Sajjad Ali Yuanhong Wang shengyang Pang Jian li Sufang Tang institute of Metal Research Chinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaHefei 230026China Department of Physics Southern University of Science and TechnologyShenzhen 518055China The 31st Research institute of china Aerospace Science and Industry Corp Beijing 100074China

Although the electromagnetic-coupling chemical vapor infiltration(E-CVI)has been proven of a highefficiency technique for producing carbon fiber reinforced pyrocarbon(Py C)matrix(C/C)composites,a deep understanding of the deposition kinetics and mechanism of Py C matrix is still *** this work,a deposition model with uniform electric field but gradient magnetic field was set up by using unidirectional carbon fiber bundles as the substrates to investigate the deposition kinetics and ***,the polarizability,and the chemical adsorption and dehydrogenation barriers of hydrocarbon were simulated based on the density functional theory(DFT)and the Climb-image nudged elastic band method,*** E-CVI process exhibited extremely high Py C deposition rates of 8.7,11.5,16.5 and 22.7 nm/s at 700,750,800 and 850℃,respectively,together with a significantly low apparent activation energy of 57.9 k J/mol within the first 5 *** Py C deposited at different temperatures with different time shows a smooth laminar structure with low coherent length and graphitization *** theoretical calculation and simulation results indicated that the electrons existing on the carbon fibers and the accelerated motion of radicals with preferred orientation forced by the derived magnetic field have reduced the energy barrier for the deposition process,thereby resulting in low apparent activation energy and high Py C deposition *** results of this work may shed a light on how to better direct the preparation of C/C composites by E-CVI process with high quality and efficiency.

关键词： Electromagnetic-coupling chemical vapor infiltration CVI C/C composites Deposition mechanism

Effect of C/SiC Volume Ratios on Mechanical and Oxidation Behaviors of C_(f)/C-SiC Composites Fabricated by Chemical Vapor Infiltration Technique

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Acta Metallurgica Sinica(English Letters) 2022年第5期35卷 801-811页

作者： Jinjin Yao shengyang Pang Yuanhong Wang Chenglong Hu Rida Zhao Jian li Sufang Tang Hui-Ming Cheng institute of Metal Research Chinese Academy of SciencesShenyang110016China School of Materials Science and Engineering University of Science and Technology of ChinaHefei230026China The 31St Research institute of china Aerospace Science and Industry Corp Beijing100074China Shenzhen institute of Advanced technology Chinese Academy of SciencesShenzhen518055China

C/SiC volume ratios in carbon fiber-reinforced carbon-silicon carbide(C_(f)/C-SiC)composites may influence greatly mechanical and oxidation properties of the composites,but have not been well investigated ***,C_(f)/C-SiC composites with different C/SiC volume ratios were fabricated by chemical vapor infiltration(CVI)technique through alternating the thickness of a pyrocarbon(PyC)*** composites with C/SiC volume ratios of 0.37 and 0.84 exhibited the better comprehensive mechanical *** CS0.37 showed the highest flexural strength of 340.6 MPa,and CS0.84 had the maximum tensile strength of 139.1 *** excellent mechanical properties were closely related to the relatively low C/SiC volume ratios and porosities,optimum interfacial bonding and reduced matrix *** composite with a low C/SiC volume ratio of 0.10 showed the best anti-oxidation performance due to its high SiC *** oxidation mechanisms at 1100℃and 1400℃were discussed by considering the effect of the C/SiC volume ratios,pores and matrix micro-cracks,oxidation of carbon phase and SiC.

关键词： C_(f)/C-SiC composites Chemical vapor infiltration Mechanical properties Oxidation properties

Synthesis of monolithic carbon aerogels with high mechanical strength via ambient pressure drying without solvent exchange

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Journal of Materials Science & technology 2020年第15期47卷 66-74页

作者： Zhi Yang Jian li Xiaojing Xu shengyang Pang Chenglong Hu Penglei Guo Sufang Tang Hui-Ming Cheng institute of Metal Research Chinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaHefei 230026China Aerospace Business Department China Academy of Launch Vehicle TechnologyBejing 100076China

A simple,fast and cost-effective method for monolithic carbon aerogels(CAs) preparation was proposed through sol-gel polycondensation of resorcinol with fo rmaldehyde in a basic aqueous solution followed by ambient pressure drying without solvent exchange,and *** microstructure and network strength of CAs were tailored by adju sting the catalyst concentration([resorcinol]/[sodium carbonate] in the range of 300-2000),water content([deionized water]/[resorcinol] equals to 17 and 24,respectively),and gelation temperature(Tgel in the range of 30-90℃).Resultantly,the CAs with a wide range of density(0.30-1.13 g/cm3),high specific surface area(465-616 m2/g),high compressive strength(6.5-147.4 MPa)and low thermal conductivity(0.065-0.120 W·m-1 K-1) were obtained in this ***,the largesized CAs(100×100×20 mm3) can also be prepared by this method since the formed robust skeleton network can resist shrinkage/collapse of pore structure and prevent cracking during *** improved mechanical strength and monolithic forming abilities could be mainly attributed to the uniform arrangement of carbon particles and pores,fine particle size,abundant network structure and enhanced particle neck.

关键词： Carbon aerogels Ambient pressure drying High mechanical strength Thermal insulation