检索结果-内蒙古大学图书馆

Atomic surface of cobalt-chromium-molybdenum alloy induced by novel green chemical mechanical polishing through controlling pH values and oxidation processes

引用

Applied Surface science 2024年 652卷

作者： Liu, Haoran Zhang, Zhenyu Deng, Xingqiao Yu, Jiaxin Shi, Chunjing Zhou, Hongxiu Meng, Fanning Feng, Junyuan State Key Laboratory of High-performance Precision Manufacturing Dalian University of Technology Dalian 1160214 China Yantai Research Institute Harbin Engineering University Yantai 264000 China School of Mechanical and Electrical Engineering Chengdu University of Technology 610059 China School of Manufacturing Science and Engineering Southwest University of Science and Technology Mianyang 621010 China School of Mechanical Engineering Hangzhou Dianzi University Hangzhou 310018 China School of Energy and Power Engineering Dalian University of Technology Dalian 116024 China

Cobalt-chromium-molybdenum (CoCrMo) alloy has superior wear resistance, high corrosion resistance and excellent biocompatibility. However, these properties make CoCrMo alloy become a difficult-to-machine material. Nevertheless, high-performance CoCrMo devices strictly require the surface roughness Ra less than 1 nm, arising a challenge for ultraprecision machining. To overcome the challenge, a novel green chemical mechanical polishing (CMP) is developed, including silicon oxide, hydrogen peroxide, tartaric acid and deionized water. After CMP, surface roughness Ra of 0.16 nm is achieved for CoCrMo alloy. Compared with those published on CoCrMo alloys previously, the surface roughness is the lowest. X-ray photoelectron and infrared spectroscopies reveal that hydrogen peroxide dominated the oxidation processes in CMP. Co oxides were softened and dissolved by hydrogen ions. Relatively, Cr and Mo oxides showed better stability and less dissolution in tartaric acid, avoiding excessive corrosion. The remaining oxides are removed by silicon oxide. The metal ions released are chelated by tartaric acid during the polishing process. The chelation formulas of metal ions and tartaric acid are further proposed. The developed novel green CMP provide new insights to manufacture atomic surface on an alloy with high corrosion and wear resistances, which is beneficial for the potential applications on medical devices. © 2024 Elsevier B.V.

关键词： CMP CoCrMo alloy Oxidation processes pH value Tartaric acid

来源：评论

学校读者我要写书评

暂无评论

Frequency-dependent squeezing via Einstein–Podolsky–Rosen entanglement based on silicon nitride microring resonators

arXiv

引用

arXiv 2024年

作者： Xu, Haodong Shu, Zijun Li, Nianqin Shen, Yang Ji, Bo Yang, Yongjun Wu, Tengfei Long, Mingliang He, Guangqiang State Key Laboratory of Advanced Optical Communication Systems and Networks Department of Electronic Engineering Shanghai Jiao Tong University Shanghai200240 China State Key Laboratory of Precision Spectroscopy East China Normal University Shanghai200062 China Science and Technology on Metrology and Calibration Laboratory Changcheng Institute of Metrology Measurement Aviation Industry Corporation of China Beijing100095 China Shanghai Astronomical Observatory Chinese Academy of Sciences China

Significant efforts have been made to enhance the performance of displacement sensors limited by quantum noise, such as gravitational wave detectors. Techniques like frequency-dependent squeezing have overcome the standard quantum limit in optomechanical force measurements, leading to substantial overall progress. These advancements, coupled with major developments in integrated photonics, have paved the way for the emergence of integrated Kerr quantum frequency combs (QFCs). A platform has been established for designing EPR entangled quantum frequency combs using on-chip silicon nitride microring resonators, enabling thorough analysis and optimization of entanglement performance, as well as effective noise reduction adjustments. This platform, incorporating the quantum dynamics of Kerr nonlinear microresonators, supports at least 12 continuous-variable quantum modes in the form of 6 simultaneous two-mode squeezed pairs (EPR entangled pairs). Additionally, by selecting the detection angle of the idler mode, a single-mode squeezed state is generated in the signal mode. Given the frequency-dependent nature of the detection angle, frequency-dependent squeezing is achieved. A comparative analysis of the results under different dispersion conditions is also conducted. Copyright © 2024, The Authors. All rights reserved.

关键词： Silicon nitride

来源：评论

学校读者我要写书评

暂无评论

CMAS attack behavior of air plasma sprayed thermal barrier coatings with big pores

引用

Journal of the European Ceramic Society 2022年第13期42卷 6159-6169页

作者： Shan, Xiao Wu, Di Cai, Huangyue Luo, Lirong Yang, Lixia Jia, Libing Guo, Fangwei Zhao, Xiaofeng Shanghai Key Laboratory of Advanced High-temperature Materials and Precision Forming School of Materials Science and Engineering Shanghai Jiao Tong University Shanghai200240 China Aero Engine Corporation of China Shanghai Commercial Aircraft Engine Manufacturing Co. Ltd Shanghai201306 China Engineering Research Center of Nano-Geo Materials of Ministry Education Faculty of Materials Science and Chemistry China University of Geosciences Wuhan430074 China College of Material Science and Technology Nanjing University of Aeronautics and Astronautics Nanjing210016 China Power Generation Siemens Energy Co. Ltd Shanghai200082 China

Previous studies indicated that big globular pores in air plasma sprayed (APS) thermal barrier coatings (TBCs) are more likely to remain after calcium-magnesium-alumino-silicates (CMAS) attack than are small ones. In this research, therefore, the CMAS attack behavior of an APS TBC with more big globular pores was investigated. It was demonstrated that the more-big-globular-pores APS TBC exhibited better resistance to exfoliation and intergranular corrosion, and chemical degradation than normal APS TBCs, while its pores can be easily filled by CMAS. Analysis on pore structures and CMAS infiltration characteristics indicated that the morphologies of the transition regions between the globular and the crack network pores may play an import role in determining the CMAS filling behavior for globular pores in APS TBCs. © 2022 Elsevier Ltd

关键词： Plasma spraying

来源：评论

学校读者我要写书评

暂无评论

Preparation, structural characteristics, and application of walnut isolated protein-propylene glycol alginate complex loaded chlorogenic acid freshness preservation film

引用

Chemical Engineering Journal 2025年 516卷

作者： Wang, Zilin Zhou, Yifan Dai, Jiahe Shi, Chongying Wang, Yifan Tao, Liang Sheng, Jun Tian, Yang College of Food Science and Technology Yunnan Agricultural University Kunming650201 China Engineering Research Center of Development and Utilization of Food and Drug Homologous Resources Ministry of Education Yunnan Agricultural University Kunming650201 China Yunnan Key Laboratory of Precision Nutrition and Personalized Food Manufacturing Yunnan Agricultural University Kunming650201 China Puer University Puer665000 China

To enhance the utilization of protein-rich walnut meal, this study developed coacervates by leveraging the structural reinforcement capacity of propylene glycol alginate (PGA) to stabilize walnut protein isolate (WNPI). Through charge-driven electrostatic assembly technology, chlorogenic acid (CA) was encapsulated into WNPI/PGA nanoparticles (encapsulation efficiency: 92.30% at 4:1 WNPI/PGA-CA ratio), which were then blended with PVA to fabricate multifunctional films. Mechanistic analysis confirmed that electrostatic attraction between WNPI's [sbnd]NH3+ and PGA's [sbnd]COO– governed coacervation at the optimal 2:1 WNPI/PGA ratio. The WNPI/PGA-CA films demonstrated tensile strength similar to PVA films, with reduced water vapor and oxygen permeability, and exhibited dual antioxidant and antibacterial properties, enabling pork preservation with low lipid oxidation. This work pioneers the dual-functional use of WNPI/PGA as both a CA carrier and film reinforcer, offering a scalable strategy for processing byproducts of protein upcycling and intelligent food packaging. © 2025

关键词： Chlorogenic acid Complex coacervates Green preservative films Propylene glycol alginate Walnut protein isolate

来源：评论

学校读者我要写书评

暂无评论

Reduce Wear and Control Friction for Copper-Based Powder Metallurgy Wet Friction Material by Optimizing Porosity, Surface Roughness and Surface Texture

SSRN

引用

SSRN 2023年

作者： Chen, Zhi Chen, Yuedu Tang, Wuzhong Zhang, Guojun Han, Fenglin Zhang, Zhizhong State Key Laboratory of Precision Manufacturing for Extreme Service Performance College of Mechanical and Electrical Engineering Central South University Changsha410083 China AECC Hunan Aviation Powerplant Research Institute Zhuzhou410315 China Central South University China Guangdong HUST Industrial Technology Research Institute China

Due to the excellent thermal conductivity, stable friction performance and relatively high mechanical properties, copper-based powder metallurgy friction materials are widely used in many fields such as aerospace, high-speed trains, wind power generation and automobiles. In order to ensure long service life, high reliability, high transmission power or braking efficiency, low wear rate and relatively high friction coefficient are always the pursuit goals of copper based powder metallurgy friction materials. However, researchers had proposed many methods to reduce the wear rate of friction materials, which also reduced the friction coefficient. This is not conducive to the transmission of power or braking efficiency of friction materials. To address this issue, this paper investigates the effects of porosity, surface roughness and surface texture on the friction coefficient and wear rate of wet friction materials. The experimental results show that as the porosity increases, the compressive strength decreases, the friction coefficient and wear rate increase. As the surface roughness increases, the friction coefficient and wear first decrease and then increase. Compared to other surface textures, trapezoidal surface texture can achieve the maximum friction coefficient and lowest wear rate. The porosity of 20.4%, surface roughness of 1.629μm and trapezoidal surface texture are selected as the optimal combination for copper-based powder metallurgy wet friction material with relatively high friction coefficient and low wear rate. Compared to the original friction material, this combination increases the friction coefficient by 18.2%, and reduces the wear rate by 53.2%. This study can provide theoretical basis for the preparation of friction materials for high rotational speed and high load capacity. © 2023, The Authors. All rights reserved.

关键词： Friction

来源：评论

学校读者我要写书评

暂无评论

Subsurface Deformation and Crack Propagation between 3C-SiC/6H-SiC Interface by Applying In-Situ Laser-Assisted Diamond Cutting RB-SiC

SSRN

引用

SSRN 2022年

作者： Zhang, Jianguo Fu, Yufan Yu, Yongjing Chen, Xiao Zhang, Junjie Xiao, Junfeng Xu, Jianfeng State Key Laboratory of Digital Manufacturing Equipment and Technology School of Mechanical Science and Engineering Huazhong University of Science and Technology Wuhan430074 China School of Mechanical Engineering Hubei University of Technology Wuhan430068 China National Innovation Institute of Digital Design and Manufacturing Wuhan430206 China Center for Precision Engineering Harbin Institute of Technology Harbin150001 China

Reaction-bonded silicon carbide (RB-SiC) is considered as an excellent optical material in aerospace engineering. However, the multiple complex interfaces and high hardness make it difficult to be precisely machined. In this research, the in-situ laser-assisted diamond cutting was applied to precisely machining RB-SiC. Firstly, Raman spectroscopy was adopted to identify 3C-SiC and 6H-SiC components in RB-SiC. As following, the in-situ laser-assisted diamond cutting was experimentally carried out to analyze the subsurface deformation and fracture in detail. It was clarified that the cross slips and high-density stacking faults significantly enhance the plastic deformation of RB-SiC. Moreover, the dislocations rapidly plugged at the intersection of 3C-SiC/6H-SiC interfaces resulting in the lateral crack which propagates along the [111]//[0001] direction. © 2022, The Authors. All rights reserved.

关键词： Silicon carbide

来源：评论

学校读者我要写书评

暂无评论

Effect of the interlayer temperature on microstructure and mechanical behavior of the high-strength low-alloy steel manufactured by the wire arc additive manufacturing

引用

Materials Today Communications 2025年 46卷

作者： Li, Ming Zhang, Wei Zhou, Zhukun Liang, Jiahua Sun, Xuan Wang, Wei Mo, Hongyuan Shang, Xin Chen, Shenggui Long, Yu Zhang, Lijuan School of Resources Environment and Materials Guangxi University State Key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite Structures Guangxi Nanning530004 China Institute of Science&Technology Innovation Dong Guan University of Technology Dong Guan523000 China Institute of Laser Intelligent Manufacturing and Precision Processing School of Mechanical Engineering Guangxi University Nanning530004 China School of Art and Design Guangzhou Panyu Polytechnic Guangzhou511483 China

The thermal history distribution in thin-walled parts deposited by WAAM was non-uniform, leading to variations in properties at different deposition heights. In this study, using CMT-WAAM technology with controlled interlayer temperatures, thin-walled parts were deposited from HSLA steel under various interlayer temperature parameters. The performance differences were correlated with the microstructural changes caused by the different thermal cycle processes experienced by two sets of thin-walled parts. The EBSD data revealed that thin-walled parts deposited with a parameter of 100 °C interlayer temperature exhibited a dispersed distribution of carbides, while those deposited with a 300 °C interlayer temperature had carbides aggregated into carbide clusters. The dispersed carbides caused the 1# thin-walled part to exhibit a yield platform during deformation. As the deposition height increased, the yield strength (σy) showed an overall decreasing trend, dropping from 730.53 MPa at the bottom to 636.06 MPa in the middle and further to 580.86 MPa at the top. This variation in yield strength was related to the baking process experienced by the 1# thin-walled part, with the yield strength being enhanced at the bottom. For the 2# thin-walled part, the clustered carbides resulted in continuous yield. The yield strength at the top was 451.64 MPa, the yield strength in the middle was abnormally 448.84 MPa, and the yield strength at the bottom reached the highest value of 531.91 MPa. Yield plateaus were observed in the engineering stress-strain curves at the bottom and middle of the 1# thin-walled parts, a phenomenon similar to the bake-hardening specimens reported in previous studies. The strengthening phenomenon similar to the bake-hardening mechanism observed in CMT-WAAM was noteworthy. © 2025

关键词： Stress-strain curves

来源：评论

学校读者我要写书评

暂无评论

Interactional Relations between Ablation and Heat Affected Zone (Haz) in Laser Cutting of Glass Fiber Reinforced Polymer (Gfrp) Composite by Fiber Laser

SSRN

引用

SSRN 2022年

作者： Huang, Shaofu Fu, Zhendong Liu, Chao College of Mechanical Engineering Anhui University of Science and Technology Huainan China Nanjing University of Aeronautics and Astronautics Jiangsu Key Laboratory of Precision and Micro-Manufacturing Technology Nanjing China Institute of Environment-friendly Materials and Occupational Health Anhui University of Science and Technology Wuhu241003 China

Laser technology is widely used in the processing of various composite materials. Ablation and heat affected zone (HAZ) are important phenomena in laser processing, but the relationship between ablation and HAZ defects has not been deeply researched. In this paper, laser cutting of glass fiber reinforced polymer (GFRP) was investigated by means of fiber laser. To assess the influence of the process parameters on ablation and HAZ, four main parameters were selected as the experimental factor in single factor experimental study. The degree of material ablation was judged according to the phenomenon of light spot and plume in processing, and the width of HAZ was measured by optical microscope. The experimental analysis shows that the HAZ defects by the ablation phenomenon can be evaluated to reveal the relationship between ablation and HAZ. On this basis, improving the ablation condition is helpful to reduce the formation of HAZ. © 2022, The Authors. All rights reserved.

关键词： Laser ablation

来源：评论

学校读者我要写书评

暂无评论

Enhanced High-Temperature Wear Resistance of Gcr15 Steels Balls by Generating a Ti+Nb Diffusion Layer Via Mechanical Alloying and Nh3·H2o Treatment

SSRN

引用

SSRN 2023年

作者： Xie, Xincheng Guo, Zhongning Liang, Zhongwei Xiao, Jinrui Zhao, Zhuan State Key Laboratory of Precision Electronic Manufacturing Technology and Equipment Guangdong University of Technology Guangzhou510006 China Guangdong Engineering Research Centre for Strengthen Grinding and Micro\Nano High-Performance machining Guangzhou University Guangzhou510006 China School of physics and materials science Guangzhou University Guangzhou510006 China

In this study, mechanical alloying and NH3·H2O treatmentGCr15 steel balls were used to strengthen GCr15 steel balls. The steel balls were first coated with a Ti+Nb coating using ball mill equipped with a home-made grind jar, followed by a NH3·H2O treatment in a common jar to remove the Ti+Nb coating. Surprisingly, a Ti+Nb diffusion layer with a thickness of 5.1µm was generated. The mechanical properties of both processed sample and unprocessed samples were investigated, including grains, dislocations, microhardness, residual stress, and friction properties at different temperatures. The results showed that the processed sample had obvious grain refinement and large dislocation density, with maximum microhardness and compressive residual stress values of 934HV and -490 MPa, respectively. Moreover, the processed samples exhibit great high-temperature wear resistance. In particular, the friction coefficient drop to 0.26 at 400°C, which was 52.73% less than that of unprocessed samples. These findings indicated that the proposed method can improve the high-temperature resistance of some mechanical components, especially for steel balls. © 2023, The Authors. All rights reserved.

关键词： Microhardness

来源：评论

学校读者我要写书评

暂无评论

Silicon Carbide Nano-Via Arrays Fabricated by Double-Sided Metal-Assisted Photochemical Etching

SSRN

引用

SSRN 2022年

作者： Chen, Yun Li, Zijian Shi, Dachuang Dong, Shankun Chen, Xin Gao, Jian State Key Laboratory of Precision Electronic Manufacturing Technology and Equipment School of Electromechanical Engineering Guangdong University of Technology Guangzhou510006 China Department of Mechanical and Aerospace Engineering The Hong Kong University of Science and Technology Clear Water Bay Kowloon Hong Kong

Silicon carbide (SiC) has gradually dominated the market of power semiconductor electronic devices because of its excellent electrical properties and chemical stability. However, fabricating micro/nano structures in SiC that are crucial for device functioning has been challenging. In this paper, a novel double-sided metal-assisted photochemical etching was proposed to efficiently fabricate SiC nano-via arrays. The experimental results demonstrated that the vertical etching rate of double-sided MAPCE was ~1.2 times higher than that of traditional MAPCE. The etching rate of SiC was found to be closely related to the type of noble metal, the concentration of oxidant (H2O2) and the UV light power density. The mechanism of double-sided MAPCE was disclosed as that the photogenerated electron-hole pairs were separated by the electronic field created by the H2O2 reduction which was catalyzed by the bottom metal layer, therefore, more photogenerated holes participated in SiC etching, resulting in a boost of etching rate. The proposed method may provide a feasible and economical way to process various wide bandgap semiconductors. © 2022, The Authors. All rights reserved.

关键词： Silicon carbide

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：