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人工智能技术在失效分析领域的应用

航空材料学报 2024年第5期44卷 1-16页

作者：李桌汉有移亮赵子华骆红云吴素君张峥钟群鹏北京航空航天大学材料科学与工程学院北京100191

本文探讨了人工智能技术,尤其是机器学习和自然语言处理技术在失效分析领域的应用与发展趋势。失效分析是确保设备可靠性和安全性的重要手段,广泛应用于航空航天、汽车制造、电子设备等领域。传统的失效分析方法通常依赖专家经验,而人... 详细信息

本文探讨了人工智能技术,尤其是机器学习和自然语言处理技术在失效分析领域的应用与发展趋势。失效分析是确保设备可靠性和安全性的重要手段,广泛应用于航空航天、汽车制造、电子设备等领域。传统的失效分析方法通常依赖专家经验,而人工智能技术凭借其强大的数据处理能力,与传统方法相结合,极大地提升了分析的精度和效率。在失效模式诊断方面,人工智能技术能够快速准确地识别各种故障模式,并提供精确的诊断结果;在失效原因诊断中,人工智能通过整合多种数据来源,揭示复杂的失效因素和潜在的因果关系,提升了诊断的可靠性;在失效预测方面,机器学习技术能够精确预测材料的寿命和强度,减少实验时间和成本;在失效预防方面,人工智能技术提供了新的思路,能够有效降低失效发生的风险,减少产品维护成本。本文还展望了人工智能技术在失效分析领域的发展前景,提出了在数据质量提升、模型优化、跨学科合作以及伦理与安全等方面的挑战与建议。

关键词：人工智能机器学习自然语言处理失效分析失效诊断寿命预测失效预防

Effect of alloying elements on microstructure, mechanical and damping properties of Cr-Mn-Fe-V-Cu high-entropy alloys

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Journal of Materials Science & Technology 2018年第11期34卷 2014-2021页

作者： Ruokang Song Fan Ye Chenxi Yang sujun wu School of Materials Science and Engineering Beihang University (BUAA)

A series of new Cr-Mn-Fe-V-Cu high-entropy alloys were prepared by arc melting and suction *** is found that with the addition of Cu, the structure of the alloys evolved from BCC ＋ BCC1 phases to BCC ＋ FCC phases. With increase of Cu, the volume fraction of the Cu-Mn-rich FCC phase increased, and the morphology of the FCC phase transformed from granular particles to long strips and blocks. Compared with other reported HEAs, the Cr-Mn-Fe-V-Cu HEAs exhibit a good balance between strength and ductility. The CrMn0.3 FeVCu0.06 alloy with granular FCC particles exhibits the highest compressive yield strength（1273 MPa） and excellent ductility（εf= 50.7%）. Quantitative calculations for different strengthening mechanisms demonstrate that dislocation and precipitate strengthening are responsible for high strength of the CrMn0.3 FeVCu0.06 alloy, while the solid solution strengthening effect is very low because of its small atomic-size difference. In addition, the CrMn0.3 FeVCu0.06 alloy exhibits good damping capacity due to its high dislocation and interface damping effects. Therefore, the dislocation density and distribution of FCC phase are the crucial factors for improvement of both mechanical properties and damping capacity of the HEAs.

关键词： High-entropy alloy Phase formation Mechanical properties Damping capacity

Influence of different rolling processes on microstructure and strength of the Al–Cu–Li alloy AA2195

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Progress in Natural Science:Materials International 2022年第1期32卷 87-95页

作者： Fan Ye Ling Mao Jian Rong Baoshuai Zhang Lijun Wei Sihan Wen Haojun Jiao sujun wu International Research Center for Advanced Structural and Biomaterials School of Materials Science and Engineering Beihang University School of Materials Science and Engineering Beihang University Aerospace Research Institute of Materials & Processing Technology

The influence of different rolling processes on precipitation behaviour, crystallography texture, grain morphology,and their consequent effects on tensile properties for Al–Cu–Li alloy AA2195 was investigated in the present *** H-T8 samples(hot rolled + T8) presented better tensile strength and ductility(with serious strength anisotropy) than the HC-T8 samples(hot rolled + cold rolled + T8), due to their different microstructures and textures. The higher dislocation density was found in the H-T8 samples, which promoted the nucleation of main strengthening phase T1in the matrix and suppressed the grain boundary precipitation, resulted in better strength and ductility. The increase of the dynamic recovery(DRV) during hot rolling enhanced the generation of Brass texture, and brought serious strength anisotropy. The cold rolling was performed after the hot-rolling process for the HC-T8 samples which increased deformation energy and resulted in full recrystallization of the deformed microstructure during the following solution treatment. The formation of recrystallized microstructure reduced the dislocation density and the heterogeneous precipitate nucleation positions which limited the strengthening phase precipitation in matrix and accelerated the precipitation along grain boundaries, resulted in fewer T1precipitates, coarse grain-boundary precipitates(GBPs), and wider precipitate-free zones(PFZs). The localized strain may be concentrated on the grain boundary to induce the dislocation pile-up, breaking of the GBPs, and intergranular fracture during stretching.

关键词： Al-Cu-Li alloys Rolling Mechanical properties Microstructure evolution Fracture

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大豆GPAT基因家族鉴定及生物信息学分析

大豆科技 2024年第3期 7-15页

作者：吴苏峻王宇王艳丽张锴乔亚科河北科技师范学院农学与生物科技学院/河北省作物逆境生物学重点实验室河北秦皇岛066000 河北科技师范学院园艺科技学院河北秦皇岛066000

为了解植物油脂肪酸积累通路中关键基因GPAT在大豆脂质合成中的作用,文章通过生物信息学方法对大豆GPAT基因家族进行鉴定和表达分析。结果表明,大豆全基因组中共鉴定获得89个GmGPAT基因,分布在20条染色体上。系统进化分析表明大豆GPAT... 详细信息

为了解植物油脂肪酸积累通路中关键基因GPAT在大豆脂质合成中的作用,文章通过生物信息学方法对大豆GPAT基因家族进行鉴定和表达分析。结果表明,大豆全基因组中共鉴定获得89个GmGPAT基因,分布在20条染色体上。系统进化分析表明大豆GPAT基因家族的多样性和功能分化与拟南芥和蒺藜苜蓿基因家族演化趋势相似。GmGPAT基因家族结构具有复杂性和多样性,不同基因在调控和功能上存在差异,该基因启动子含有多种逆境胁迫和激素响应调控元件。基因家族共线性分析表明不同植物基因组具有相似性和差异性。GmGPAT表达模式可分为4簇,第I簇中各基因在花芽中表达量相对较高,第Ⅳ簇中各基因在籽粒中表达量相对较高,表明该基因可能与花芽和籽粒的发育调控相关。

关键词：大豆基因家族 GmGPAT 生物信息分析

Simulation of an aircraft thermal management system based on vapor cycle response surface model

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Chinese Journal of Aeronautics 2024年第6期37卷 64-77页

作者： Haodong LIU Hongsheng JIANG sujun DONG Longxian XUE Yongji LIU Jianjun wu School of Aeronautic Science and Engineering Beihang UniversityBeijing 100191China Chengdu Aircraft Design and Research Institute Aviation Industry Corporation of ChinaChengdu 610091China

The modern aircraft Thermal Management System(TMS)faces significant challenges due to increasing thermal loads and limited heat dissipation *** optimize TMS during the conceptual design stage,the development of a modeling and simulation tool is *** this study,a TMS simulation model library was created using MATLAB/*** simplify the complexity of the Vapor Cycle System(VCS)model,a Response Surface Model(RSM)was constructed using the Monte Carlo method and validated through simulation *** the F-22 fighter TMS as an example,a thermal dynamic simulation model was constructed to analyze the variation of thermal response parameters in key subsystems and elucidate their coupling ***,the impact of total fuel flow and ram air flow on the TMS was *** findings demonstrate the existence of an optimal total fuel flow that achieves a balance between maximizing fuel heat sink utilization and minimizing bleed air *** adaptive distribution of fuel and ram air flow was found to enhance aircraft thermal management *** study contributes to improving modeling efficiency and enhancing the understanding of the thermal dynamic characteristics of TMS,thereby facilitating further optimization in aircraft TMS design.

关键词： Thermal management sys-tem Vaporcycle Response surface model Dynamic simulation MonteCarlo

Fatigue Crack Growth Behavior of Different Zones in an Annealed Automatic Gas Tungsten Arc Weld Joint of TA16 and TC4 Titanium Alloys

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Journal of wuhan University of Technology(Materials Science) 2020年第6期35卷 1090-1097页

作者： SHAO Ling wu sujun PENG Wenya DATYE Amit JU Hongbo LIU Ying Research Institute of Zhejiang University-Taizhou Zhejiang UniversityTaizhou 318000China School of Materials Science and Engineering Beihang UniversityBeijing 100191China AECC Hunan Aviation Powerplant Research Institute Zhuzhou 412000China Department of Mechanical Engineering&Materials Science Yale UniversityNew HavenCT 06511USA Key Laboratory of Advanced Welding Technology of Jiangsu Province Jiangsu University of Science and TechnologyZhenjiang 212003China Institute of Technology of Aircraft Engine Beijing Research Institute of Aviation EngineeringBeijing 100024China

Based on the investigated microstructure of different zones in the annealed automatic gas tungsten arc weld joint of TA16 and TC4 titanium alloys,the mechanical property of them was assessed under fatigue crack growth rate *** evaluation of fatigue crack growth rate,three points bending specimens were *** correlation between the range of stress intensity factor and crack growth rate was determined in different zones of the annealed weld *** crack growth rates were obviously different in different zones of weld joint of dissimilar titanium alloys,due to their different *** electron microscope examinations were conducted on the fracture surface in order to determine the relevant fracture mechanisms and crack growth mechanisms with respect to the details of microstructure.

关键词： dissimilar titanium alloys joining weld joint microstructure fatigue crack growth rate fracture

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调磁环材料性能对永磁齿轮损耗的影响研究

机械工程学报 2022年第22期58卷 269-275页

作者：鲁仰辉罗帅吴素君北京航空航天大学材料科学与工程学院北京100191 国家电投集团科学技术研究院有限公司北京102209

磁场调制型永磁齿轮作为一种新型永磁变速装置,易产生较大磁场损耗,降低永磁齿轮工作效率,限制其传递能力的进一步提升。提出整体成型动力传动式调磁环提高了扭矩传动能力,建立调磁环三维模型开展了强度、刚度和损耗计算,并结合永磁齿... 详细信息

磁场调制型永磁齿轮作为一种新型永磁变速装置,易产生较大磁场损耗,降低永磁齿轮工作效率,限制其传递能力的进一步提升。提出整体成型动力传动式调磁环提高了扭矩传动能力,建立调磁环三维模型开展了强度、刚度和损耗计算,并结合永磁齿轮性能测试分析了调磁环骨架材料和调磁极片材料的损耗,研究三种不同调磁环承载骨架材料参数对永磁齿轮损耗和效率的影响,对永磁齿轮参数进行优化并确定最优扭矩骨架承载材料。结果表明,特种工程塑料调磁环骨架材料能大幅降低永磁齿轮损耗,有效提升传动效率,永磁齿轮实测传动效率可达93.8%。

关键词：磁齿轮永磁变速损耗调磁环材料特种工程塑料

K417G服役涡轮导向叶片的组织性能及热疲劳损伤机理分析

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稀有金属材料与工程 2019年第5期48卷 1517-1522页

作者：宋若康马东吴素君北京航空航天大学

对服役后低压涡轮导向叶片的组织性能及热疲劳行为进行了系统研究,结果表明,K417G合金在服役后组织发生明显的弱化,γ’相的网状组织长大、粗化严重高温拉伸与室温拉伸试验结果的对比表明,K417G合金在高温下力学性能出现大幅降低,这主... 详细信息

对服役后低压涡轮导向叶片的组织性能及热疲劳行为进行了系统研究,结果表明,K417G合金在服役后组织发生明显的弱化,γ’相的网状组织长大、粗化严重高温拉伸与室温拉伸试验结果的对比表明,K417G合金在高温下力学性能出现大幅降低,这主要是由于合金内析出相之间的相界面和晶界在高温下成为合金的薄弱环节,易成为裂纹的起源位置,从而降低了强度,断裂方式也从室温下的韧性断裂逐渐转变为沿晶特征的脆性断裂;叶片在热疲劳应力作用下表面的涂层发生开裂、脱落,基体合金被氧化,氧化物在应力作用下开裂、脱落而形成疲劳裂纹源;热疲劳试验数据的拟合结果表明随着温度循环周次的增加,裂纹扩展速率呈减小的趋势,这是由于随循环周次的增加,二次裂纹出现并生长,释放了热应力,从而降低了裂纹扩展速率。

关键词： K417G合金导向叶片组织弱化热疲劳

一对一责任制助产护理模式对初产妇分娩方式和产程的影响研究

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中国全科医学 2019年第A1期22卷 213-216页

作者：吴素君浙江省兰溪市妇幼保健计划生育服务中心妇产科

目的探究和分析一对一责任制助产护理模式对初产妇分娩方式和产程的影响。方法选择兰溪市妇幼保健计划生育服务中心妇产科2017-01-01至2018-08-30收治的初产妇200例为研究对象。采用随机数字表法将其分为对照组和研究组,各100例。对照... 详细信息

目的探究和分析一对一责任制助产护理模式对初产妇分娩方式和产程的影响。方法选择兰溪市妇幼保健计划生育服务中心妇产科2017-01-01至2018-08-30收治的初产妇200例为研究对象。采用随机数字表法将其分为对照组和研究组,各100例。对照组采用常规助产护理模式干预,研究组采用一对一责任制助产护理模式干预。对比两组分娩方式(顺产、剖宫产),第一、二、三产程时间,产后2 h出血量,新生儿Apgar评分,母婴不良事件发生率。结果研究组顺产率(85.0%)高于对照组(61.0%)(P0.05)。研究组产后2 h出血量﹝(86.8±20.6)ml﹞少于对照组﹝(124.5±27.9)ml﹞,新生儿Apgar评分﹝(9.2±0.7)分﹞高于对照组﹝(7.3±0.8)分﹞(P<0.05)。研究组母婴不良事件发生率(2.0%)低于对照组(19.0%)(P<0.05)。结论对初产妇采用一对一责任制助产护理模式干预,不仅能提高产妇顺产率、缩短其总产程时间,还能减少其产后出血量、降低母婴不良事件发生率,对提高初产妇分娩质量和保障母婴安全具有重要意义。

关键词：围生期医护一对一责任制助产护理模式分娩产程初产妇