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Acta Metallurgica Sinica(English Letters) 2020年第1期33卷 165-171页

作者： Dan Chen Jinglong Li Huaxia Zhao Zhejun Tan Jiangtao Xiong State Key Laboratory of Solidifi cation Processing Northwestern Polytechnical UniversityXi’an 710072China Shaanxi Key Laboratory of Friction Welding Technologies Northwestern Polytechnical UniversityXi’an 710072China AVIC Manufacture Technology Institute Beijing 100024China

Friction stir lap welding was conducted on 2 mm + 2 mm sheets of aluminum alloy 2 A12-T4. The plunge depth(PLD) was designed as 2.45–2.58 mm, which was varied in submillimeters as 2.45, 2.50, 2.53, 2.55, and 2.58 mm, and the axial force was recorded in the welding process. The results show that the PLD fluctuation in submillimeters causes significant variation in the axial force and affects the voids(i.e., Void I and Void II), hook, and effective sheet thickness(EST), among which Void I is the main factor that affects the EST. The fracture load–PLD function in the tensile shear test of the joints follows the rule of the EST–PLD function. An optimized PLD is approximately 2.55 mm, at which the EST reaches 1.71 mm, corresponding to a peak fracture load of 11.03 kN. Thus, a PLD of 2.55 mm is suggested with a tolerance of 0.02 mm, corresponding to a fracture load of 9.6–11.0 kN, i.e., within a fluctuation of 12%.

关键词： Submillimeter plunge depth Mechanical properties Friction stir lap welding

Experimental investigation of submerged impinging jets in a plunge pool downstream of large dams

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Science China(Technological Sciences) 1998年第4期41卷 357-365页

作者：刘沛清高季章李永梅 China Institute of Water Conservancy and Hydroelectric Power Research Beijing China

Submerged impinging jets in a plunge pool downstream of large dams are experimentally investigated in details. By use of the hot\|film anemometer, the velocity field in the plunge pool produced by middle orifices of 1∶400 scale Xiluodu spillway model is measured. The diffusive characteristics and energy dissipation mechanism of the submerged impinging jet in the plunge pool are analyzed.

关键词： impinging jet plunge pool energy dissipation.

Effect of tool plunge depth on reinforcement particles distribution in surface composite fabrication via friction stir processing

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Defence Technology（防务技术） 2017年第2期13卷 86-91页

作者： Sandeep Rathee Sachin Maheshwari Arshad Noor Siddiquee Manu Srivastava Division of Manufacturing Processes and Automation Engineering(MPAE) Netaji Subhas Institute of Technology Department of Mechanical Engineering Jamia Millia Islamia A Central University

Aluminium matrix surface composites are gaining alluring role especially in aerospace, defence, and marine industries. Friction stir processing(FSP) is a promising novel solid state technique for surface composites fabrication. In this study, AA6061/SiC surface composites were fabricated and the effect of tool plunge depth on pattern of reinforcement particles dispersion in metal matrix was investigated. Six varying tool plunge depths were chosen at constant levels of shoulder diameter and tool tilt angle to observe the exclusive effect of plunge variation. Process parameters chosen for the experimentation are speed of rotation, travel speed and tool tilt angle which were taken as 1400 rpm, 40 mm/min, and 2.5 °respectively. Macro and the microstructural study were performed using stereo zoom and optical microscope respectively. Results reflected that lower plunge depth levels lead to insufficient heat generation and cavity formation towards the stir zone center. On the other hand, higher levels of plunge depth result in ejection of reinforcement particles and even sticking of material to tool shoulder. Thus, an optimal plunge depth is needed in developing defect free surface composites.

关键词： Metal matrix composites Friction stir processing Tool plunge depth Microstructural characterization

Influence of tool plunge depth and welding distance on friction stir lap welding of AA5454-O aluminum alloy plates with different thicknesses

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中国有色金属学会会刊：英文版 2012年第S3期22卷 624-628页

作者： Jun-Won KWON Myoung-Soo KANG Sung-Ook YOON Yong-Jai KWON Sung-Tae HONG Dae-Il KIM Kwang-Hak LEE Jong-Dock SEO Jin-Soo MOON Kyung-Sik HAN School of Materials Science and Engineering University of Ulsan School of Mechanical Engineering University of Ulsan Technical Research Laboratories Shin Young Co.Ltd. Automotive Parts Innovation Center Ulsan Technopark

AA5454-O aluminum alloy plates with thicknesses of 1.4 and 1.0 mm were friction-stir-lap-welded (FSLWed).The influences of the tool plunge depth and welding distance on surface appearance,macrostructure and mechanical properties of the FSLWed plates were experimentally investigated.The tensile shear load of the FSLWed plates was compared with that of the adhesive-bonded plates.Defect-free FSLWed zones were successfully obtained in all the tool plunge depths and the welding distances.The FSLWed zones exhibited the relatively smooth surface morphologies.Under all the FSLWed conditions,the FSLWed zone exhibited higher average hardness than the base metal.In addition,the upper plate exhibited a higher average hardness than the lower plate,although there was no special tendency in spite of the change in the tool plunge depth and the welding distance.The maximum tensile shear load of the FSLWed plates was much higher than that of the adhesive-bonded aluminum alloy plate.Especially,under the FSLW condition of the plunge depth of 1.8 mm and the welding distance of 40 mm,the tensile shear load of the FSLWed plate reached a level about 41% greater than that of the adhesive-bonded aluminum alloy plate.In addition,the maximum tensile shear load of the FSLWed plate was increased with the increase of the welding distance.

关键词： friction stir lap welding AA5450-O aluminum alloy tool plunge depth welding distance mechanical properties

A new type of plunge pool―Multi-horizontal submerged jets

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Science China(Technological Sciences) 2008年第12期51卷 2128-2141页

作者： DENG Jun,XU WeiLin,ZHANG JianMing,QU JinXue & YANG YongQuan State Key Laboratory of Hydraulics and Mountain River Engineering,Sichuan University,Chengdu 610065,China State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University Chengdu China

Based on the understanding of the mechanism of energy dissipation,a new type of plunge pool is presented with the advantages of high rate of energy dissipation,low impact pressure,and small close-to-bed velocity on the soleplate of the plunge pool.The first advantage owes to enlarged shearing energy dissipation areas in the plunge pool,while the other two are caused by the jet that enters in a nearly horizontal level to keep the soleplate from being scoured directly.All of the above arrangements make this new type of energy dissipator distinct from the underflow energy dissipation.Through experiments on the physical model,the authors found that the water flow maintained stable and submerged in horizontal direction when the flow was narrow in horizontal but thick in vertical direction.However,the wide flat nappe was ready to submerge or float as the downstream water level rised or dropped.The entire flow fields of multi-horizontal submerged jets into plunge pool were also numerically simulated.The numerical results of water surface curve,close-to-bed velocity and floor pressure agree well with the experimental data.The flow pattern in the plunge pool was analyzed after combining the laboratory data and numerical simulation.

关键词： hydraulic engineering 3-D flow field numerical simulation plunge pool submerged jets

Safety evaluation and the static-dynamic coupling analysis of counter-arched slab in plunge pool

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Science China(Technological Sciences) 2009年第5期52卷 1397-1412页

作者： LIAN JiJian LIU XiZhu MA Bin School of Civil Engineering Tianjin UniversityTianjin 300072China

The stability of plunge pool slab of drainage structure is crucial to energy dissipation,but the working conditions of counter-arched slab are very complex and its stress procedure is considerably nonlinear and coupling.Therefore,a nonlinear static and dynamic coupling method to analyze the counter-arched slab configuration is put forward,which can reflect the coupling of dynamic loads,slab,anchor bars,groundwork and abutment as well as the dynamic procedure of instability.Various nonlinear factors and static-dynamic coupling are taken into consideration,and the working conditions,stress mechanism,dynamic instability procedure and influential instability factors are revealed.The proposed method thus provides a comprehensive safety evaluation method of plunge pool,which further pro-vides an important theoretical basis for engineering design of counter-arched slab in plunge pool.

关键词： draw-off project plunge pool counter-arched slab stability static-dynamic coupling analysis safety evaluation

Influences of tool plunge speed and tool plunge depth on friction spot joining of AA5454-O aluminum alloy plates with different thicknesses

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中国有色金属学会会刊：英文版 2012年第S3期22卷 629-633页

作者： Sung-Ook YOON Myoung-Soo KANG Yong-Jai KWON Sung-Tae HONG Dong-Hwan PARK Kwang-Hak LEE Chang-Yong LIM Jong-Dock SEO School of Materials Science and Engineering University of Ulsan School of Mechanical Engineering University of Ulsan Institute of E-Vehicle Technology University of Ulsan Technical Research Laboratories Shin Young Co.Ltd.

AA5454-O aluminum alloy plates with the thicknesses of 1.4 and 1.0 mm were friction-spot-joined (FSJed).The plunge speed of the joining tool was changed in a range of 100 500 mm/min under a constant rotation speed of 500 r/min.The plunge depth was ranged from 1.6 mm to 2.2 mm.The tool plunge speed did not make a remarkable effect on the surface appearance and macro-structure of the FSJed zone.The average hardness of the FSJed zone was greater than or equal to that of the base metal.However,there was no remarkable tendency in the average hardness change of the FSJed zone in spite of the variation in the tool plunge speed and tool plunge depth.The increase of the tool plunge depth resulted in the increase of the tensile shear load.However,the change of the tool plunge speed did not lead to the remarkable variation in the tensile shear load of the FSJed plates.It was noteworthy that the FSJed plate exhibited the highest tensile shear load of about 4.0 kN.

关键词： friction spot joining AA5454-O aluminum alloy plunge speed plunge depth mechanical property

Design of plunge Shaving Cutters for Finishing internal Gears

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Journal of Harbin Institute of Technology(New Series) 1996年第3期3卷 66-70页

作者：刘俐平李华敏孙建华

ＤｅｓｉｇｎｏｆＰｌｕｎｇｅＳｈａｖｉｎｇＣｕｔｔｅｒｓｆｏｒＦｉｎｉｓｈｉｎｇ　ｉｎｔｅｒｎａｌＧｅａｒｓＬＩＵＬｉｐｉｎｇ；ＬＩＨｕａｍｉｎ；ＳＵＮＪｉａｎｈｕａ（刘俐平，李华敏，孙建华）（Ｄｅｐｔ．ｏｆＭｅｃｈ... 详细信息

ＤｅｓｉｇｎｏｆＰｌｕｎｇｅＳｈａｖｉｎｇＣｕｔｔｅｒｓｆｏｒＦｉｎｉｓｈｉｎｇ　ｉｎｔｅｒｎａｌＧｅａｒｓＬＩＵＬｉｐｉｎｇ；ＬＩＨｕａｍｉｎ；ＳＵＮＪｉａｎｈｕａ（刘俐平，李华敏，孙建华）（Ｄｅｐｔ．ｏｆＭｅｃｈａｎｉｃａｌＥｎｇｉｎｅｅｒｉｎｇ...

关键词： ss: internal gear plunge shaving correction

CHARACTERISTIC ANALYSIS OF THE PLUNGING OF TURBIDITY CURRENTS

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Journal of Hydrodynamics 2010年第2期22卷 274-282页

作者： AN Rui-dong LI Jia State key Laboratory of Hydraulics and Mountain River Engineering Sichuan University Chengdu 610065China College of Water Recourse and Hydropower Sichuan University Chengdu 610065 China

Turbidity currents are flows driven by suspended sediment of flood-induced turbid river water with excess density.Such currents are often the governing factor in reservoir sedimentation by transporting fine materials over long distances and delivering the majority of deposition,which thus reduces the storage capacity.Therefore,the design and operation of a reservoir requires an accurate prediction of its occurrence condition and plunging position,which is the objective of the present study.This article presents a verified algebraic slip mixture model including momentum,continuity and algebraic velocity expressions to simulate 2-D turbidity currents.Test experiments in a multiphase flume were carried out.Reynolds number,sediment concentration and densimetric Froude number were used as parameters in the occurrence condition analysis.The plunging of turbidity currents may produce reflux and backflow due to the diving flow at the surface of the clear water.The similar experimental results were also obtained by PIV measurements

关键词： turbidity current plunge suspend sediment algebraic slip mixture model densimetric Froude number

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