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Failure mechanisms and surface treatment processes of thermal barrier coatings:Review

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Chinese Journal of Aeronautics 2024年第9期37卷 20-40页

作者： Hao LI shengqiang yang Xiuhong LI Wenhui LI College of Mechanical and Vehicle Engineering Taiyuan University of TechnologyTaiyuan 030024China Shan.xi Province Key Laboratory of Precise Machining Taiyuan University of TechnologyTaiyuan 030024China College of Aeronautics and Astronautics Taiyuan University of TechnologyTaiyuan 030024China

Thermal Barrier Coatings(TBCs)technology is key to improving the service temperature and the productivity of aircraft *** performance and failure life of TBCs are strongly influenced by surface integrity and ***,recognizing failure mechanisms and developing effective surface treatment processes are crucial for further improving the reliability and durability of *** paper explains the primary reasons for TBC failure,emphasizing on how integrity of surface and interface influences interfacial oxidation,high-temperature erosion,and Calcium-Magnesium-Alumina-Silicate(CMAS)***,this paper completely and rigorously evaluates the research status of TBCs surface treatment processes,including the characteristics and effects of various processes,and describes the requirements and goals of pretreatment and *** addition,a potential direction for the development and application of TBCs surface treatment is suggested.

关键词： Thermal BarrierCoatings(TBCs) Failure Surface treatment processes Processing goals Mass finishing

Amending Research on the Expression of the Contact Force of the Spindle Barrel Finishing Based on EDEM Simulation

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Chinese Journal of Mechanical Engineering 2020年第6期33卷 105-117页

作者： Na Wang shengqiang yang Tingting Zhao Bo Cao Chengwei Wang College of Mechanical and Vehicle Engineering Taiyuan University of TechnologyTaiyuan030024China Shanxi Key Laboratory of Precision Machining Taiyuan University of TechnologyTaiyuan030024China

The spindle barrel finishing is commonly used to improve the surface integrity of the important parts of the high-end equipment while it is difficult to provide enough test artifacts for the traditional trial and error experiment to obtain the desirable processing *** EDEM simulation of the spindle barrel finishing can provide effective help for the process design,however,the difference between the simulation and experiment is closely related to the selection of the contact model during *** this paper,simulations and experiments are conducted based on the identical apparatus and conditions to facilitate the comparison and validation between each *** on the Hertz contact theory,the effect of the material properties of contact objects and the relative position of the workpiece on the contact force is *** expression of the correlation coefficient of the contact model is *** the formula for calculating the contact force between the barrel finishing abrasive and the workpiece that includes influence coefficient of the material properties and the relative positions is ***,the contact force calculation formula is verified by changing the rotating *** result shows that the material correction coefficient ranges from 1.41 to 2.38,which is inversely related to the equivalent modulus *** position correction coefficient ranges from 2.0 to *** relative error value between the calculation result and the experimental test result is from 0.58%to 14.07%.This research lay a theoretical foundation for the correction theory of the core elements of the spindle barrel finishing process.

关键词： Spindle barrel finishing processing EDEM simulation Hertz-Mindlin(no slip)contact model Average contact force Modified coefficient

Calibrated explosive triangle for determining capacity of explosion of gas mixtures

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Mining Science and Technology 2011年第4期21卷 567-571页

作者： Cheng Jianwei yang shengqiang Sun Qi School of Safety Engineering China University of Mining ＆ Technology Xuzhou 221116 China State Key Laboratory of Coal Resource and Mine Safety China University of Mining ＆ Technology Xuzhou 221008 China

Determination of the capacity for explosion of gas mixtures in a sealed area is very important for mining *** this capacity is high,it would be very dangerous for rescue workers to proceed with their rescue operations.A number of methods have been developed to determine the capacity for explosion of gas mixtures in sealed *** of the more popular methods is the Coward explosive triangle,published by *** presented a fast and easy way to determine the capacity for explosion of gas mixtures,which has proved to be a very useful tool for mining engineers and members of rescue ***,due to few drawbacks in this method;potential errors would be introduced when it is *** a brief introduction we first describe the Coward method and then,we propose and discuss new calibrated explosive *** demonstrate the method in two case studies where we compare our results with those of the old *** results indicate that the calibrated method have improved accuracy and ***,assessments can be made more accurately.

关键词： Explosive triangle Gas explosion Explosive capacity of gas mixtures

Spontaneous combustion influenced by surface methane drainage and its prediction by rescaled range analysis

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International Journal of Mining Science and Technology 2018年第2期28卷 215-221页

作者： shengqiang yang Xincheng Hu Wei Victor Liu Jiawen Cai Xiuhong Zhou School of Safety Engineering China University of Mining&TechnologyXuzhou 221008China Key Laboratory of Gas and Fire Control for Coal Mines Xuzhou 221008China Department of Civil&Environmental Engineering University of AlbertaEdmonton T6G 2W2Canada

This study established numerical modeling using COMSOLTMto examine the influence of horizontal location and drainage ability of surface borehole on spontaneous combustion in longwall working face gob. Rescaled Range Analysis(R/S analysis) was employed to investigate the chaos characteristic of N_2/O_2 ratio from a surface borehole in 10416 working face gob, yangliu Colliery, China. The simulation results show that there is always a circular ‘‘dissipation zone" around the drainage borehole and an elliptic ‘‘spontaneous combustion zone" in deep gob. Little influence was found on spontaneous combustion zone on the intake side of the gob but the width of spontaneous combustion zone in middle gob is enlarged, while the depth of spontaneous combustion zone near the return side is reduced. The R/S analysis indicates that the influence of surface borehole on spontaneous combustion can be divided into two stages by the chaos feature of N_2/O_2: safety drainage stage and spontaneous combustion initiating stage. It can be concluded that the methane drainage from gob through surface borehole can intervene in the distribution of spontaneous combustion zone in gob and the chaos feature of N_2/O_2 from surface borehole can effectively reflect coal spontaneous combustion condition in gob.

关键词： Coal spontaneous combustion Surface drainage borehole Hurst index Rescaled range analysis Methane drainage Symbiotic disaster

Restraining effect of nitrogen on coal oxidation in different stages:Non-isothermal TG-DSC and EPR research

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International Journal of Mining Science and Technology 2020年第3期30卷 387-395页

作者： Tongyu Zhao shengqiang yang Xincheng Hu Wanxin Song Jiawen Cai Qin Xu State Key Laboratory of Coal Resources and Safety Mining China University of Mining and TechnologyXuzhou 221116China School of Safety Engineering China University of Mining and TechnologyXuzhou 221116China Key Laboratory of Gas and Fire Control for Coal Mines(China University of Mining and Technology) Ministry of EducationXuzhou 221116China Department of Civil&Environmental Engineering University of AlbertaEdmonton T6G 2W2Canada

Nitrogen is widely used to prevent the spontaneous combustion of coal in underground coal mines. A spontaneous combustion-prone coal seam was studied to investigate the restraining effect of nitrogen on coal oxidation in different oxidation stages, based on non-isothermal thermogravimetry-differential scanning calorimetry(TG-DSC) and electron paramagnetic resonance(EPR) experiments. We found that the key feature temperatures grow steadily with increasing nitrogen in the oxidation environment,resulting in longer oxidation stages. The most significant finding is that there is a stagnation of the inhibitory effect of nitrogen on coal oxidation in the range of 85.0–95.0% nitrogen in the slow and the rapid oxidation stages, owing to the competitive adsorption of coal by nitrogen and oxygen. However, the restraining effect cannot be reflected by the kinetic parameters of the coal before it reaches the thermal decomposition and combustion stage. Nitrogen can also affect free radical types and free radical concentrations during coal oxidation: the higher the concentration of nitrogen in the oxidation environment, the greater the number of free radical types and the lower the free radical concentration. This experimental study improves the understanding of the restraining effect of nitrogen on coal oxidation in different oxidation stages and provides an important reference for coal fire prevention in spontaneous combustionprone coal seams.

关键词： Reaction heat Non-isothermal TG-DSC Activation energy Pre-exponential factor Free radical

Experimental study on the goaf flow field of the ‘‘U+I” type ventilation system for a comprehensive mechanized mining face

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International Journal of Mining Science and Technology 2015年第6期25卷 1003-1010页

作者： Yu Zhaoyang yang shengqiang Qin Yi Hu Xincheng Cheng Jianwei State Key Laboratory of Coal Resources and Safe Mining China University of Mining & Technology School of Safety Engineering China University of Mining & Technology Mining Engineering College Guizhou University

＂U＂ and ＂U＋I＂ type ventilation experiments were performed on a three-dimensional fully mechanized caving face simulation experimental platform. The distribution laws of the pressure field and gas field in the mine goal were obtained. Results show that the flow field in the goaf is generally asymmetric; the location of the gas accumulation area changes with ventilation parameters and can be used as an evaluation indicator to study the air leakage extent in the goal. Hence, drainage pipes buried in the goaf to intensively extract gas can be designed in such gas areas, which can give considerations in both improving gas drainage efficiency and reducing air leakage. By comparing the gas extraction effect of model experiments with that of on-site underground practices, the basic laws are commonly consistent according to comparative analysis. Thus the experimental results can be used to guide the application of underground gas prevent!o_n_***..

关键词： Goaf flow fieldInner interlocked tail roadwayPressure fieldGas fieldGas center areaVentilation-air-methane efficiency

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基于光整加工技术改善发动机性能的实验研究

农业机械学报 2006年第2期37卷 17-20页

作者：杨胜强李文辉杨世春太原理工大学机械工程学院

以LL480QB型柴油机为实验研究对象。选定17种摩擦副零件。分类制定了光整加工工艺。重点分析了光整加工前后零件棱边。毛刺，表面的粗糙度、硬度、微观形状及应力的变化。实验结果表明：可以有效去除零件毛刺，棱边倒圆整齐。表面粗糙... 详细信息

以LL480QB型柴油机为实验研究对象。选定17种摩擦副零件。分类制定了光整加工工艺。重点分析了光整加工前后零件棱边。毛刺，表面的粗糙度、硬度、微观形状及应力的变化。实验结果表明：可以有效去除零件毛刺，棱边倒圆整齐。表面粗糙度值明显降低一个等级，表面显微硬度提高60HV以上。表面应力由拉应力转换为压应力。通过整机性能测试对比，摩擦副零件全面光整加工后的整机性能提高，按磨合指标要求，整机出厂磨合时间减少近50％，试车燃油消耗量减少30％左右，燃油消耗率减少3～4g／（kW·h），噪声降低1dB。综合表明，对摩擦副零件进行光整加工是改善发动机整机性能的有效途径之一。

关键词：光整加工发动机性能摩擦副零件表面质量

棉花黄萎病菌拮抗细菌TUBP1的分离鉴定及其防病作用

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棉花学报 2014年第5期26卷 445-451页

作者：曾红杨生强塔里木大学生物保护利用重点实验室新疆阿拉尔843300 新疆兵团农一师12团29连新疆阿拉尔843300

为研制和开发新疆棉花黄萎病优良生防菌剂,采用琼脂平板扩散法,通过初筛和复筛,分离得到一株对棉花黄萎病菌(Verticillium dahliae)具有较强抑菌活性的拮抗菌株TUBP1。通过对形态观察、生理生化实验、16S rDNA和gyrB的基因序列分析,确... 详细信息

为研制和开发新疆棉花黄萎病优良生防菌剂,采用琼脂平板扩散法,通过初筛和复筛,分离得到一株对棉花黄萎病菌(Verticillium dahliae)具有较强抑菌活性的拮抗菌株TUBP1。通过对形态观察、生理生化实验、16S rDNA和gyrB的基因序列分析,确定该菌株为Bacillus axarquiensis;利用生长速率法和牛津杯法分别测定了发酵液对棉花黄萎病菌抑菌活性,对棉花黄萎病菌菌丝生长抑制率为78.62%±3.48%,抑菌圈直径为21.00±3.86 mm。温室盆栽试验中,TUBP1最大生防效果为43.67%,小区试验中,TUBP1最大生防效果为43.07%。

关键词：棉花黄萎病菌拮抗细菌TUBP1 鉴定 Bacillus axarquiensis 拮抗作用防治效果

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基于动态差值法的直流系统绝缘监测技术

电工技术学报 2015年第1期30卷 235-241页

作者：周军朱博楠杨圣强王鹏东北电力大学电气工程学院吉林132012

针对常用直流系统绝缘监测方法的不足,提出了一种新型直流系统绝缘在线监测方法—动态差值法。即利用两次投切电阻后的电压变化量与漏电流变化量的比值来检测支路接地故障。该方法克服了绝缘监测装置的检测死区,克服了由于传感器零点漂... 详细信息

针对常用直流系统绝缘监测方法的不足,提出了一种新型直流系统绝缘在线监测方法—动态差值法。即利用两次投切电阻后的电压变化量与漏电流变化量的比值来检测支路接地故障。该方法克服了绝缘监测装置的检测死区,克服了由于传感器零点漂移影响支路绝缘电阻计算的准确性造成的漏报和误报,提高了检测灵敏度和准确性。现场运行表明了此方法的准确与可靠。

关键词：直流系统绝缘监测接地故障动态差值法