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Development of New Wear-Resistant Surface Coating at Elevated Temperature

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Journal of Iron and Steel Research International 2006年第5期13卷 37-40,59页

作者： li Shang-ping FENG Di luo he-li ZHANG Xi-e CAO Xu Institute of Superalloy Central Iron and Steel Research Institute Beijing 100081 China

Because of good oxidation resistance at high temperature and excellent mechanical properties of Ni3 Al and high hot hardness, and good oxidation resistance of chromium carbide, chromium carbide particle reinforced Ni3Al matrix composite would possess excellent wear resistance at elevated temperature. Cr3 C2-NiAl-Ni welding wire was produced by pressureless sintering process in vacuum. When the welding wire was welded on the surface of carbon steel, under the action of the physical heat of arc, NiAl reacted with nickel to form Ni3 Al and carbide particle reinforced Ni3 Al matrix composite was formed on the welding layers. Cr3 C2 was dissolved during welding and dispersed Cr7C3 was formed, which strengthened the Ni3Al matrix significantly. The CrTC3-Ni3Al interface was broadened, and a zone of interdiffusion and a new phase M23 C6 were formed, indicating that a good bond has been formed. The hardness of Cr7 C3/Ni3 Al composite at room and elevated temperatures is much higher than that of stellite alloys. In addition, CrTC3/Ni3Al composite possesses better high temperature oxidation resistance than stellite 12 alloy. So Cr7 C3/ Ni3 Al composite can become an attractive potential candidate for elevated temperature wear-resistant surface material.

关键词： Ni3Al chromium carbide composite wear resistance elevated temperature

Abrasive Performance of Chromium Carbide Reinforced Ni_3Al Matrix Composite Cladding

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Journal of Iron and Steel Research International 2009年第5期16卷 87-91页

作者： li Shang-ping luo he-li FENG Di CAO Xu ZHANG Xi-e Institute of High-Temperature Materials China Iron and Steel Research Institute Group Beijing 100081 China

The Mierostrueture and room temperature abrasive wear resistance of chromium carbide reinforced Ni3Al matrix composite cladding at different depth on nickel base alloy were investigated. The results showed that there is a great difference ih microstructure and wear resistance of the Ni3 Al matrix composite at different depth. Three kinds of tests, designed for different load and abrasive size, were used to understand the wear behaviour of this material. Under all three wear conditions, the abrasion resistance of the composite cladding at the depth of 6 mm, namely NC- M2, was much higher than that of the composite cladding at the depth of 2 mm, namely NC-M1. In addition, the wear-resistant advantage of NC-M2 was more obvious when the size of the abrasive was small. The relative wear resistance of NC-M2 increased from 1.63 times to 2.05 times when the size of the abrasive decreased from 180 μm to 50 μm. The microstructure of the composite cladding showed that the size of chromium carbide particles, which was mainly influenced by cooling rate of melting pool, was a function of distance from the interface between the coating and substrate varied gradually. The chromium carbide particles near the interface were finer than that far from interface, which was the main reason for the different wear resistance of the composite cladding at different depth.

关键词： Ni3 Al chromium carbide composite abrasive wear

Wear Evaluation on Ni_3Al/MnS Composite Related to Metallurgical Processes

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Journal of Iron and Steel Research International 2012年第7期19卷 46-54页

作者： Karin Gong luo he-li ZHOU Zhi-feng TIAN Zhi-ling Lars Nyborg li Chang-hai Department of Materials and Manufacturing Technology Chalmers University of Technology Gothenburg Se-412 96 Sweden China Iron and Steel Research Institute Group Beijing 100081 China Department of Manufacturing Engineering and Engineering Management City University of Hong Kong Hong Kong China

Iron alloyed Ni3Al with composition of Ni-18. 8Ab10. 7Fe-0. 5Mn-0. 5Ti-0. 2B in atom percent （NAC alloy） showed attractive tribological properties under unlubrication condition at room temperature. The alloy was prepared by hot isostatic pressing （HIP） process. The wear properties were associated with its intrinsic deformation mechanism. Unfortunately, the single phase NAC-alloy worked inadequately with its counterpart disk, and also showed a poor machinability. In the present work, NAC-alloy matrix composite with 6 % （volume percent） MnS particle addi- tion was studied to improve its wear behaviors and performance on machining. Two metallurgical processes of HIP and vacuum casting were applied to produce the testing materials. Pin-on-disk （POD） measurements were carried out at room temperature. A commercial vermicular graphite cast iron was selected as a reference material. The counter- part disk was made of a grey cast iron as liner material in ship engines. The contact pressures of 2.83 MPa and 5.66 MPa were normally applied in the tests. The investigation indicated that MnS particle addition in the NAC-alloy composites functions as an effective solid lubricant, and improved wear properties and machinability of the materials. Obvi- ously, as-cast NAC-alloy with in-situ formed MnS-phase was working more effectively with the counterpart, compa- ring to the HIPed NAC-alloy composite with MnS particles. At the high contact pressure of 5.66 MPa, the specific wear rate of the as-cast NAC-alloy composite was high. The phenomenon of the negative effect is mostly due to the brittle second NiAl phase as evidenced in the microstructure analysis.

关键词： HIP processing friction coefficient specific wear rate intermetallics sliding wear casting machinability

Impact of ocean data assimilation on the seasonal forecast of the 2014/15 marine heatwave in the Northeast Pacific Ocean

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 24-31页

作者： Tiantian Tang Jiaying he Huihang Sun Jingjia luo Institute for Climate and Application Research(ICAR)/Key Laboratory of Meteorological Disaster Nanjing University of Information Science and TechnologyNanjingChina

A remarkable marine heatwave,known as the“Blob”,occurred in the Northeast Pacific Ocean from late 2013 to early 2016,which displayed strong warm anomalies extending from the surface to a depth of 300 *** study employed two assimilation schemes based on the global Climate Forecast System of Nanjing University of Information Science(NUIST-CFS 1.0)to investigate the impact of ocean data assimilation on the seasonal prediction of this extreme marine *** sea surface temperature(SST)nudging scheme assimilates SST only,while the deterministic ensemble Kalman filter(EnKF)scheme assimilates observations from the surface to the deep *** latter notably improves the forecasting skill for subsurface temperature anomalies,especially at the depth of 100-300 m(the lower layer),outperforming the SST nudging *** excels in predicting both horizontal and vertical heat transport in the lower layer,contributing to improved forecasts of the lower-layer warming during the *** improvements stem from the assimilation of subsurface observational data,which are important in predicting the upper-ocean *** results suggest that assimilating ocean data with the EnKF scheme significantly enhances the accuracy in predicting subsurface temperature anomalies during the Blob and offers better understanding of its underlying mechanisms.

关键词： Seasonal forecast Ocean data assimilation Marine heatwave Subsurface temperature

Cr_3C_2/Ni_3Al表面耐磨堆焊材料的焊接性

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焊接学报 2006年第4期27卷 21-24页

作者：李尚平冯涤骆合力钢铁研究总院高温材料研究所北京100081

Cr3C2/Ni3Al复合材料是一种极具潜力的高温表面耐磨堆焊材料,焊接性对于该材料的推广应用至关重要。将真空烧结制得的Cr3C2-NiAl-Ni焊条堆焊于碳钢和耐热钢表面,可形成无焊接裂纹的Cr3C2/Ni3Al复合材料堆焊层,表明Cr3C2/Ni3Al复合材料... 详细信息

Cr3C2/Ni3Al复合材料是一种极具潜力的高温表面耐磨堆焊材料,焊接性对于该材料的推广应用至关重要。将真空烧结制得的Cr3C2-NiAl-Ni焊条堆焊于碳钢和耐热钢表面,可形成无焊接裂纹的Cr3C2/Ni3Al复合材料堆焊层,表明Cr3C2/Ni3Al复合材料具有良好的焊接性,适于作为铁基材料表面耐磨堆焊材料推广应用。分析认为,Cr3C2/Ni3Al复合材料具有良好焊接性的原因在于:(1)焊接过程中,Cr3C2发生溶解再析出,熔池中的C优先被氧化,保护了Al的氧化。(2)从铁基材料基材中扩散入到焊层中的Fe元素和Cr3C2溶解而固溶于焊层中的Cr元素有效地改善了Ni3Al基体的焊接性。

关键词： Ni3Al Cr3C2 表面耐磨焊接性

一种新型Ni_(3)Al基高温耐磨合金的显微组织和性能研究

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铸造 2023年第9期72卷 1105-1108页

作者：侯杰李尚平骆合力北京钢研高纳科技股份有限公司北京100081

针对我国新一代航空发动机叶冠表面强化用高温耐磨材料的迫切需求,采用熔炼铸造法制备出一种以碳化铬和NiAl相作为耐磨硬质相的新型Ni_(3)Al基高温耐磨合金。显微组织分析、室温硬度测试、高温抗氧化性测试结果显示,两种耐磨硬质相大量... 详细信息

针对我国新一代航空发动机叶冠表面强化用高温耐磨材料的迫切需求,采用熔炼铸造法制备出一种以碳化铬和NiAl相作为耐磨硬质相的新型Ni_(3)Al基高温耐磨合金。显微组织分析、室温硬度测试、高温抗氧化性测试结果显示,两种耐磨硬质相大量析出并且均匀分布于合金中。与现役的高温耐磨材料相比,该合金同时具备高的室温硬度和1050℃时优异的抗氧化性,有望成为新一代高温耐磨材料。

关键词： Ni_(3)Al 高温耐磨合金显微组织硬度抗氧化

Brain endothelial cyclic GMP-AMP synthase(cGAS)-stimulator of interferon genes(STING)signaling pathway in aging and neurodegeneration

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Neural Regeneration Research 2025年第7期20卷 2005-2007页

作者： Bryan Sun Lulin li Jian luo Palo Alto Veterans Institute for Research VA Palo Alto Health Care SystemPalo AltoCAUSA Polytrauma System of Care VA Palo Alto Health Care SystemPalo AltoCAUSA

The cyclic GMP-AMP synthase(cGAS)-stimulator of interferon genes(STING)signaling pathway has emerged as a key mediator of *** current studies primarily attribute its effects to neurons and glial cells,emerging research suggests that cGAS-STING signaling may play a critical role in cerebral vasculature,particularly in brain endothelial ***,studying the role 7of inflammation caused by the cGAS-STING pathway in brain endothelial cells could provide a more comprehensive understanding of neuroinflammatory disease and new avenues for therapeutic ***,we review the multifaceted role of global cGAS-STING signaling in various neurological and neuroinflammatory diseases and the potential contribution of cGAS-STING in brain endothelial cells.

关键词： stimulator interferon inflammation

Interfacial Zn2+-solvation regulator towards reversible and stable Zn anode

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Journal of Energy Chemistry 2025年第1期100卷 684-692页

作者： Miao Zhou Xiongbin luo Hang li Shan Guo Zhuang Tong Xiaotao Zhou Xu li Zhaohui Hou Shuquan liang Guozhao Fang College of Mechanical Engineering Key Laboratory of Hunan Province for Advanced Carbon-based Functional Materials Hunan Institute of Science and Technology School of Materials Science and Engineering Key Laboratory of Electronic Packaging and Advanced Functional Materials of Hunan Province Central South University College of Materials and Metallurgy Guizhou University National Energy Metal Resources and New Materials Key Laboratory Central South University

Aqueous zinc-ion batteries （AZIBs） are fundamentally challenged by the instability of the electrode/electrolyte interface,predominantly due to irreversible zinc （Zn） deposition and hydrogen ***,the intricate mechanisms behind the electrochemical discrepancies induced by interfacial Zn2+-solvation and deposition behavior demand comprehensive *** molecules endowed with special functional groups （such as hydroxyl,carboxyl,etc.） have the potential to significantly optimize the solvation structure of Zn2+and regulate the interfacial electric double layer （EDL）.By increasing nucleation overpotential and decreasing interfacial free energy,these functional groups facilitate a lower critical nucleation radius,thereby forming an asymptotic nucleation model to promote uniform Zn ***,this study presents a pioneering approach by introducing trace amounts of n-butanol as solvation regulators to engineer the homogenized Zn （H-Zn） anode with a uniform and dense *** interfacial reaction and structure evolution are explored by in/ex-situ experimental techniques,indicating that the H-Zn anode exhibits dendrite-free growth,no by-products,and weak hydrogen evolution,in sharp contrast to the bare ***,the H-Zn anode achieves a remarkable Zn utilization rate of approximately 20% and simultaneously sustains a prolonged cycle life exceeding 500 ***,the H-Zn//NH4V4O10（NVO） full battery showcases exceptional cycle stability,retaining 95.04%capacity retention after 400 cycles at a large current density of 5 A *** study enlightens solvation-regulated additives to develop Zn anode with superior utilization efficiency and extended operational lifespan.

关键词： Aqueous zinc-ion batteries Interfacial reaction Asymptotic nucleation model Reversible and stable Zn anode

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弥散强化铸造合金制备工艺的研究

钢铁研究学报 2009年第11期21卷 51-55页

作者：冯硕韩伟骆合力 Karin G 李长海钢铁研究总院高温材料研究所北京100081 中国钢研科技集团公司集团办公室北京100081 Chalmers工业大学材料科学与工程学院瑞典哥德堡se41296

通过铸造实现弥散强化是不同于传统粉末冶金弥散强化的新途径。总结了现有的几种用铸造实现弥散强化的工艺。如何在钢液中获得大量超细的第二相粒子、大量超细的第二相粒子在钢液中的行为、第二相粒子在凝固前沿的行为这三个基本问题决... 详细信息

通过铸造实现弥散强化是不同于传统粉末冶金弥散强化的新途径。总结了现有的几种用铸造实现弥散强化的工艺。如何在钢液中获得大量超细的第二相粒子、大量超细的第二相粒子在钢液中的行为、第二相粒子在凝固前沿的行为这三个基本问题决定最终强化的效果。对这三个基本问题进行了理论分析,指出了工艺的几个关键点。

关键词：弥散强化铸造合金制备工艺