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Fire and Corrosion Resistances of Intumescent Nano-coating Containing Nano-SiO_2 in Salt Spray Condition

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Journal of Materials Science & Technology 2010年第1期26卷 75-81页

作者： zhenyu Wang Enhou han Fuchun Liu Wei Ke State Key Laboratory for Corrosion and Protection Institute of Metal Research Chinese Academy of Sciences Shenyang110016 China

The nano-concentrates and flame retardant nano-coating were prepared in thhis study. The effect of nano-SiO2 on the corrosion resistance and fire resistance of ammonium polyphosphate-pentaerythritol-melamine （APP- PER-MEL） coating was investigated by differential thermal analysis （DTA）, scanning electron microscopy （SEM）, effective thermal conductivity （λ/d）, X-ray photoelectron spectroscopy （XPS） and fire protection test. The chemical action and endothermic effect of ammonium polyphosphate, pentaerythritol and melamine in traditional flame retardant coating were damaged by salt spray condition, whereas the flame-retardant additives in the nano-coating demonstrated the good chemical interaction in salt spray condition. The uniformly dispersed nano-SiO2 particles could improve corrosion resistance of the coating, and hence nano-coating could remain the good fire-resistant properties even after 500 h salt spray test.

关键词： Nano-SiO2 APP-PER-MEL coating Nano-coating Salt spray test Fire-resistant property

Realization Methodology of a 5-axis Spline Interpolator in an Open CNC System

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Chinese Journal of Aeronautics 2007年第4期20卷 362-369页

作者： Wang Yongzhang Ma Xiongbo Chen Liangji han zhenyu School of Electromechanical Engineering Harbin Institute of Technology Harbin 150001 China

By making use of the advantages of non-uniform rational B-spline （NURBS） curves to represent spatial curves, an instruction format with double NURBS curves suitable for 5-axis coordinated real-time interpolation is presented to replace the current 5-axis coordinated linear interpolation method defective in low-speed, low-accuracy and enormous numerical control （NC） files in sculptured surface machining. A generation procedure of the NC files with the presented format is introduced and the method to realize the interpolation in an open computer numerical control （CNC） system is developed by ourselves. These illustrated the feasibility of the proposed method and its capability of avoiding all the shortages of 5-axis linear interpolation method.

关键词： open CNC system sculptured surface 5-axis machining NURBS interpolation

Thermal Behavior of Nano-TiO_2 in Fire-Resistant Coating

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Journal of Materials Science & Technology 2007年第4期23卷 547-550页

作者： zhenyu WANG Enhou han Fuchun LIU Wei KE Environmental Corrosion Center Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

The dispersion state of nano-TiO2 particles was studied by using transmission electron microscopy （TEM）and Fourier transform infrared spectroscopy （FT-IR）. Nanoparticles can be fully dispersed by specific hyperdispersant. The improvement of nano-TiO2 in thermal behavior and flame retardation of acrylic polymer and fire-resistant coating was investigated by differential thermal analysis （DTA）, thermogravimetry （TG）and fire-resistant time test. It is demonstrated that nano-TiO2 is helpful for enhancing the thermal stability,anti-oxidation and fire-resistant properties of acrylic polymer and fire-resistant coating.

关键词： Nano-TiO2 Fire-resistant coating Thermal stability Fire-resistant properties

CMIP6 Evaluation and Projection of Precipitation over Northern China:Further Investigation

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Advances in Atmospheric Sciences 2023年第4期40卷 587-600页

作者： Xiaoling YANG Botao ZHOU Ying XU zhenyu han Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters/Key Laboratory of Meteorological Disaster Ministry of Education/Joint International Research Laboratory of Climate and Environment ChangeNanjing University of Information Science and TechnologyNanjing 210044China School of Atmospheric Sciences Nanjing University of Information Science and TechnologyNanjing 210044China Jiangxi Vocational and Technical College of Information Application Nanchang 330043China National Climate Center China Meteorological AdmnistrationBeijing 100081China

Based on 20 models from phase 6 of the Coupled Model Intercomparison Project(CMIP6),this article explored possible reasons for differences in simulation biases and projected changes in precipitation in northern China among the allmodel ensemble(AMME),“highest-ranked”model ensemble(BMME),and“lowest-ranked”model ensemble(WMME),from the perspective of atmospheric circulations and moisture *** results show that the BMME and AMME reproduce the East Asian winter circulations better than the *** with the AMME and WMME,the BMME reduces the overestimation of evaporation,thereby improving the simulation of winter *** three ensemble simulated biases for the East Asian summer circulations are generally similar,characterized by a stronger zonal pressure gradient between the mid-latitudes of the North Pacific and East Asia and a northward displacement of the East Asian westerly ***,the simulated vertical moisture advection is improved in the BMME,contributing to the slightly higher performance of the BMME than the AMME and WMME on summer precipitation in North and Northeast *** to the AMME and WMME,the BMME projects larger increases in precipitation in northern China during both seasons by the end of the 21st century under the Shared Socioeconomic Pathway 5-8.5(SSP5-8.5).One of the reasons is that the increase in evaporation projected by the BMME is *** projection of a greater dynamic contribution by the BMME also plays a *** addition,larger changes in the nonlinear components in the BMME projection contribute to a larger increase in winter precipitation in northern China.

关键词： CMIP6 ensemble evaluation and projection moisture budget atmospheric circulation

CMIP6 Evaluation and Projection of Temperature and Precipitation over China

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Advances in Atmospheric Sciences 2021年第5期38卷 817-830页

作者： Xiaoling YANG Botao ZHOU Ying XU zhenyu han Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters/Key Laboratory of Meteorological Disaster Ministry of Education/Joint International Research Laboratory of Climate and Environment ChangeNanjing University of Information Science and TechnologyNanjing 210044China School of Atmospheric Sciences Nanjing University of Information Science and TechnologyNanjing 210044China National Climate Center China Meteorological AdministrationBeijing 100081China

This article evaluates the performance of 20 Coupled Model Intercomparison Project phase 6(CMIP6)models in simulating temperature and precipitation over China through comparisons with gridded observation data for the period of 1995–2014,with a focus on spatial patterns and interannual *** evaluations show that the CMIP6 models perform well in reproducing the climatological spatial distribution of temperature and precipitation,with better performance for temperature than for *** interannual variability can also be reasonably captured by most models,however,poor performance is noted regarding the interannual variability of winter *** on the comprehensive performance for the above two factors,the“highest-ranked”models are selected as an ensemble(BMME).The BMME outperforms the ensemble of all models(AMME)in simulating annual and winter temperature and precipitation,particularly for those subregions with complex terrain but it shows little improvement for summer temperature and *** AMME and BMME projections indicate annual increases for both temperature and precipitation across China by the end of the 21st century,with larger increases under the scenario of the Shared Socioeconomic Pathway 5/Representative Concentration Pathway 8.5(SSP585)than under scenario of the Shared Socioeconomic Pathway 2/Representative Concentration Pathway 4.5(SSP245).The greatest increases of annual temperature are projected for higher latitudes and higher elevations and the largest percentage-based increases in annual precipitation are projected to occur in northern and western China,especially under ***,the BMME,which generally performs better in these regions,projects lower changes in annual temperature and larger variations in annual precipitation when compared to the AMME projections.

关键词： CMIP6 evaluation and projection temperature precipitation ensemble

Dynamic tensile behavior of AZ31B magnesium alloy at ultra-high strain rates

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Chinese Journal of Aeronautics 2015年第2期28卷 593-599页

作者： Geng Changjian Wu Baolin Liu Fang Tong Wenwei han zhenyu Aviation Industry Corporation of China Engine Design and Research Institute School of Materials Science and Engineering Shenyang Aerospace University

The samples having {0001 } parallel to extruding direction （ED） present a typical true stress-true strain curve with concave-down shape under tension at low strain rate. Ultra-rapid ten- sile tests were conducted at room temperature on a textured AZ31B magnesium alloy. The dynamic tensile behavior was investigated. The results show that at ultra-high strain rates of 1.93 × 10^2 s^-1 and 1.70 × 10^3 s^-1, the alloy behaves with a linear stress-strain response in most strain range and exhibits a brittle fracture. In this case, {10-12} 〈 10-11 〉 extension twinning is basic deformation mode. The brittleness is due to the macroscopic viscosity at ultra-high strain rate, for which the external critical shear stress rapidly gets high to result in a cleavage fracture before large amounts of dislocations are activated. Because { 10-12} tension twinning, { 10-11 } compressive twinning, basal 〈 a 〉 slip, prismatic 〈 a 〉 slip and pyramidal 〈 c ＋ a 〉 slip have different critical shear stresses （CRSS）, their contributions to the degree of deformation are very differential. In addition, Schmid factor plays an important role in the activity of various deformation modes and it is the key factor for the samples with different strain rates exhibit various mechanical behavior under dynamic tensile loading.

关键词： AZ31B magnesium alloy Schmid factor Slip Texture Twinning

Temperature field characteristics of CF/PEEK thermoplastic composites formed by automated fiber placement using hot gas torch with slit structure nozzle

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Chinese Journal of Aeronautics 2024年第6期37卷 392-409页

作者： Ziang JIN Shouzheng SUN Sunil Chandrakant JOSHI zhenyu han Hongya FU State Key Laboratory of Robotics and System Harbin Institute of TechnologyHarbin 150001China School of Mechanical and Aerospace Engineering Nanyang Technological UniversitySingapore 639798Singapore

In-situ consolidation forming of high-performance thermoplastic composites by Automated Fiber Placement(AFP)is of significant interest in *** the laying process,the heating temperature has a great influence on the quality of the formed components.A threedimensional heat transfer finite element model of Carbon Fiber(CF)/Polyether Ether Ketone(PEEK)heated by Slit Structure Nozzle Hot Gas Torch(SSNHGT)assisted AFP is *** influence of gas flow rate,heat transfer distance,and laying speed on heating temperature is *** results show that the overall temperature increases and then decreases as the gas flow rate *** the increase in heat transfer distance and laying speed,the overall temperature ***,the gas flow rate has the greatest influence on the temperature of CF/PEEK being heated,followed by the laying speed and finally the heat transfer ***,the model can also be extended to other fiber-reinforced polymer composites formed by hot gas torch assisted AFP,which can guide the optimization of process parameters for subsequent heating temperature control.

关键词： Fiber reinforced plastics Thermoplastics Heating temperature Automated fiber placement CF/PEEK

OPEN ARCHITECTURE CNC SYSTEM HITCNC AND KEY TECHNOLOGY

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Chinese Journal of Mechanical Engineering 2007年第2期20卷 13-16页

作者： WANG Yongzhang LIU Tao FU Hongya han zhenyu School of Mechanical and Electrical Engineering Harbin Institute of Technology Harbin 150001 China

Aiming at the characteristics of modularity and reconfigurable in open architecture computer numerical control （CNC） system, the open architecture CNC system, Harbin Institute of Tech- nology computer numerical control （HITCNC）, is researched and manufactured based on the interface standards. The system＇s external interfaces are coincident with the corresponding international standards, and the internal interfaces follow the open modular architecture controller （OMAC） agreement. In the research and manufacturing process, object-oriented technology is used to ensure the openness of the HITCNC, and static programming is applied in the CNC system according to the idea of modularization disassembly. The HITCNC also actualizes real-time and unreal-time modules adopting real-time dynamical linked library （RTDLL） and component object model （COM）. Finite state ma- chine （FSM） is adopted to do dynamically modeling of HITCNC. The complete separation between the software and the hardware is achieved in the HITCNC by applying the SoftSERCANS technique. The application of the above key techniques decreases the programming workload greatly, and uses software programs replacing hardware functions, which offers plenty technique ensures for the openness of HITCNC. Finally, based on the HITCNC, a three-dimensional milling system is established. On the system, series experiments are done to validate the expandability and interchangeability of HITCNC. The results of the experiments show that the established open architecture CNC system HITCNC is correct and feasible, and has good openness.

关键词： Harbin Institute of Technology computer numerical control(HITCNC) Open architecture CNC system Interface standard Statically modeling Finite state machine (FSM) SoflSERCANS

Effect of variable-angle trajectory structure on mechanical performance of CF/PEEK laminates made by robotic fiber placement

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Chinese Journal of Aeronautics 2022年第12期35卷 336-356页

作者： Shouzheng SUN Haiyang MEI Yang WANG Jiahai ZhanG zhenyu han Jinglan GUO State Key Laboratory of Robotics and System Harbin Institute of TechnologyHarbin 150001China Wuhu Robot Technology Research Institute Harbin Institute of TechnologyWuhu 241000China Shanghai Spaceflight Precision Machinery Institute Shanghai 201600China School of Mechanical and Power Engineering Harbin University of Science and TechnologyHarbin 150080China

In comparison to the traditional fixed-angle trajectory,the variable-angle trajectory has a greater design ***,it is a challenge to determine which common design curve structure is the most effective for improving mechanical *** work explores the effects of various design curves such as fixed-angle curve,linear curve,arc curve,sine curve,Bezier curve,and cubic polynomial curve trajectories on mechanical performance of laminates,including vibration modal performance and buckling *** algorithm and improved NSGA-II algorithm are then used to optimize various curve *** results are confirmed utilizing thermoplastic Carbon Fiber(CF)/Polyether-Ether-Ketone(PEEK)laminates made by robotic fiber placement *** relationship model between different mechanical performance and curve design variables is *** optimization of variable-angle structure with mechanical properties as input variables is ***,a full-process angle-variable laying software platform from trajectory planning(CAD),trajectory optimization to manufacturing(CAM)is developed for facilitating the fiber placement application.

关键词： Fiber reinforced plastics Mechanical properties Robotic fiber placement Thermoplastics Trajectory design Variable-angle laminate