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Science China(Technological Sciences) 2024年第5期67卷 1317-1363页

作者： ZHAO JiuCheng WAN Jie ZHANG ShiZhong YAN ChuLiang ZHAO HongWei Key Laboratory of CNC Equipment Reliability Ministry of Education Jilin UniversityChangchun 130025China School of Mechanical&Aerospace Engineering Jilin UniversityChangchun 130025China Chongqing Research Institute of Jilin University Chongqing401120China School of Aeronautic Science and Engineering Beihang UniversityBeijing 102206China

The need for very-high-cycle fatigue(VHCF)testing up to 1010cycles of aviation gas turbine engine blade materials under combined mechanical loads and complex environments has encouraged the development of VHCF testing instrumentation and technology.This article begins with a comprehensive review of the existing available techniques that enable VHCF testing.Recent advances in ultrasonic fatigue testing(UFT)techniques are highlighted,containing their new capabilities and methods for single load,multiaxial load,variable amplitude fatigue,and combined cycle fatigue.New techniques for conducting UFT in high-temperature,humid environments,and corrosive environments are summarized.These developments in mechanical loading and environmental building techniques provide the possibility of laboratory construction for real service conditions of blade materials.New techniques that can be used for in situ monitoring of VHCF damage are summarized.Key issues in the UFT field are presented,and countermeasures are collated.Finally,the existing problems and future trends in the field are briefly described.

关键词： aviation gas turbine engine blade materials ultrasonic fatigue very-high-cycle fatigue high-temperature complex stress in situ testing

Fracturing behavior of brittle solids containing 3D internal crack of different depths under ultrasonic fracturing

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International Journal of Mining Science and Technology 2022年第6期32卷 1245-1257页

作者： Haijun Wang Hanzhang Li Lei Tang Jianchun Li Xuhua Ren State Key Laboratory of Hydrology-Water Resource and Hydraulic Engineering Nanjing Hydraulic Research InstituteNanjing 210029China School of Civil Engineering Institute of Future Underground SpaceSoutheast UniversityNanjing 211186China College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing 210098China

ultrasonic fracturing(UF)can be used to form crack networks for oil or gas in the mining industry and hard rock excavation.In this paper,the three-dimensional internal laser-engraved crack method(3DILC)is introduced to make penny-shaped internal crack within the samples without any damage to the surfaces.Physical experiments were performed on the transparent samples with internal cracks at different depths.The macro-and micro-fracture fractography characteristics were focused on and analyzed in details.Based on fractography,the mechanisms of the UF were revealed.The propagation paths of cracks of different depths were simulated based on the Paris fatigue model and compared with experimental results.The results show that the 3D-ILC method is a powerful tool for the experimental research on the internal crack propagation in the UF.Under the action of ultrasonic field,fractography shows the characteristics of beach marks,lance-like pattern,rime-like pattern and glass powder.It can be judged that the mechanisms of UF include high cycle fatigue fracture,shear fracture,and friction.The results of the numerical simulation using the Paris fatigue model are consistent with the experimental results.

关键词： 3D-ILC method 3D internal crack ultrasonic fracturing Fracture mechanics ultrasonic fatigue Paris fatigue model

Fracture of two three-dimensional parallel internal cracks in brittle solid under ultrasonic fracturing

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Journal of Rock Mechanics and Geotechnical Engineering 2022年第3期14卷 757-769页

作者： Haijun Wang Hanzhang Li Lei Tang Xuhua Ren Qingxiang Meng Chun Zhu State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Nanjing Hydraulic Research InstituteNanjing210029China School of Earth Sciences and Engineering Hohai UniversityNanjing210098China

Similar to hydraulic fracturing(HF), the coalescence and fracture of cracks are induced within a rock under the action of an ultrasonic field, known as ultrasonic fracturing(UF). Investigating UF is important in both hard rock drilling and oil and gas recovery. A three-dimensional internal laser-engraved crack(3D-ILC) method was introduced to prefabricate two parallel internal cracks within the samples without any damage to the surface. The samples were subjected to UF. The mechanism of UF was elucidated by analyzing the characteristics of fracture surfaces. The crack propagation path under different ultrasonic parameters was obtained by numerical simulation based on the Paris fatigue model and compared to the experimental results of UF. The results show that the 3D-ILC method is a powerful tool for UF research.Under the action of an ultrasonic field, the fracture surface shows the characteristics of beach marks and contains powder locally, indicating that the UF mechanism includes high-cycle fatigue fracture, shear and friction, and temperature load. The two internal cracks become close under UF. The numerical result obtained by the Paris fatigue model also shows the attraction of the two cracks, consistent with the test results. The 3D-ILC method provides a new tool for the experimental study of UF. Compared to the conventional numerical methods based on the analysis of stress-strain and plastic zone, numerical simulation can be a good alternative method to obtain the crack path under UF.

关键词： Three-dimensional internal laser-engraved crack(3D-ILC) Interaction of cracks ultrasonic fatigue Penny-shaped crack Fracture mechanics High-cycle fatigue

fatigue life assessment of a high strength steel 300 M in the gigacycle regime

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Theoretical & Applied Mechanics Letters 2012年第3期2卷 19-22页

作者： Hongqian Xue Pingli Liu Peng Chen Jie Wang School of Mechatronics Northwestern Polytechnical University Xi'an 710072China

The fatigue behavior of a high strength steel 300 M in the gigacycle regime was investigated. Fully reversed tension - compression fatigue tests at ambient temperature were performed using an ultrasonic fatigue system operating at 20 kHz.The staircase test method was employed to obtain accurate values of the mean fatigue strength corresponding to fixed numbers of cycles up to 10~9.These results were compared to the curve which is estimated by the data tested in the mid-long life regime on conventional servo hydraulic test machine at 20 Hz.Results indicate that the fatigue strength determined from ultrasonic fatigue testing is lightly higher than conventional testing in the range of 10~6-10~7 cycles.It is obvious that nucleations of fractures tend to occur below the surface, if fractures happen after more than 10~7 cycles.All the fractured specimens fails from internal SiO_2 inclusions or smaller carbides and carbide clusters.

关键词： 300 M steel gigacycle fatigue ultrasonic fatigue very high cycle fatigue

Effect of ultrasonic Peening Treatment on VHCF Behavior of Friction Stir Welded Joints in Aluminum Alloys

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Effect of Ultrasonic Peening Treatment on VHCF Behavior of F...

作者： Ruofan Zhang Xue Li Yongjie Liu Chao He Qingyuan Wang School of Architecture and Civil Engineering Xihua University School of Architecture and Civil Engineering Chengdu University MOE Key Laboratory of Deep Earth Science and Engineering College of Architecture and Environment Sichuan University Failure Mechanics and Engineering Disaster Prevention and Mitigation Key Laboratory of Sichuan Province Sichuan University

Studying the mechanical properties of aluminum alloy 6061 friction stir welded（FSW） joints after ultrasonic peening treatment（UPT） under very high cycle fatigue（VHCF） loading. The effect of joints ultrasonic peening treatment was explored. It can be seen from the results that the ultrasonic peening treatment can form a reinforced layer on the surface of joints, and the fatigue crack source is transferred from the surface of the specimen to the inside. However, the change of fatigue crack initiation site does not improve the fatigue strength of specimen through ultrasonic peening treatment. The fatigue strength of the aluminum alloy 6061 joint after ultrasonic peening treatment is even lower than as a received condition. The characteristics of fatigue crack initiation and the mechanism of surface strengthened layer on fatigue strength were analyzed and discussed.

关键词： friction stir welding S-N Curves ultrasonic peening treatment very high cycle fatigue ultrasonic fatigue fatigue crack initiation

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超声疲劳研究综述

机械技术史

机械技术史 1998年 685-690页

作者：陶华西北工业大学

航空、航天等工业领域中,许多机械结构(例如飞机发动机轴、涡轮盘和叶片)由于声学、空气动力学或机械运转等原因,承受着高频率(数千赫芝)、小振幅的变动载荷,因而面临超声疲劳断裂破坏的现实威胁.直升机、飞机、火箭和其它机械都曾因此... 详细信息

航空、航天等工业领域中,许多机械结构(例如飞机发动机轴、涡轮盘和叶片)由于声学、空气动力学或机械运转等原因,承受着高频率(数千赫芝)、小振幅的变动载荷,因而面临超声疲劳断裂破坏的现实威胁.直升机、飞机、火箭和其它机械都曾因此发生过结构破坏事故。由于频率高,超声疲劳短时间即可达到很高的循环周次(N=10~7～10次),若试图用常规试验技术(f≤300Hz)进行研究,仅从耗时考虑就几乎是不可能的。

关键词： ultrasonic fatigue fatigue life fatigue crack growth