CN104729918A - Dynamic pull/pressing and torsion synchronous combined loading experiment device - Google Patents
Dynamic pull/pressing and torsion synchronous combined loading experiment device Download PDFInfo
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- CN104729918A CN104729918A CN201510106511.6A CN201510106511A CN104729918A CN 104729918 A CN104729918 A CN 104729918A CN 201510106511 A CN201510106511 A CN 201510106511A CN 104729918 A CN104729918 A CN 104729918A
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Abstract
The invention provides a dynamic pull/pressing and torsion synchronous combined loading experiment device, and relates to the field of dynamic mechanical property experiment of materials. The dynamic pull/pressing and torsion synchronous combined loading experiment device comprises a transmission rod and an incidence rod which are arranged on a rolling support, wherein a test piece is mounted between the transmission rod and the incidence rod; a torsion wave loading device and a tension/compression wave loading device are arranged on the incidence rod; the distance between the tension/compression wave loading device and the end where the test part is mounted on the incidence rod is greater than that of the a torsion wave loading device and the end where the test part is mounted on the incidence rod; the tension/compression wave loading device and the torsion wave loading device are respectively connected with a controller through signal circuits. The dynamic pull/pressing and torsion synchronous combined loading experiment device is applied to dynamic mechanical property research on materials, the defects of a conventional Hopkinson pull rod can be avoided, the test part can be simultaneously loaded with tension/compression waves and torsion waves, the loaded tension/compression waves and torsion waves can simultaneously reach the test part, and meanwhile loaded incidence waves and reflection waves reflected from the test part can be also recorded, so that the experimental requirements of dynamic mechanical property research on materials can be met.
Description
Technical field
The present invention relates to In Dynamic Testing of Materials apparatus field, particularly relate to one and dynamically draw/press and turn round synchronization combining loading experimental apparatus.
Background technology
Split hopkinson bar is a kind of effective experimental provision studying material dynamic mechanical performance under one-dimensional stress state.Since Kolsky invention split hopkinson press bar devices in 1949 and with since material dynamic mechanical performance under its research one-dimensional stress state, dynamic compression experiments technology improves constantly.Separate type Hopkinson pull rod is one of major equipment doing the research of MATERIALS ' DYNAMIC tensile mechanical properties at present.The dynamic anti-shear performance of material is one of its dynamic mechanical, and to its experiment research work relative difficult, main or dependence separate type split-Hopkinson torsional bar carries out at present.In these three kinds of experimental provisions, by contrast, depression bar technology relative maturity, and pull bar and torsion bar technology have not little room for improvement.
Material dynamically may be drawn the synergy of (pressure) and torsional load under arms in process.The behavior of the material necessarily very interested important research field of mechanics worker under this synergy.The main difficulty of problem is embodied in and how suitable stretching (compression) pulse and torsional pulses is loaded on test specimen simultaneously.Because stretching ripple (wave of compression) is different from the circulation way of torsional wave (shearing wave), the former is compressional wave, the latter is shear wave, they are different in the speed of same Propagation, velocity of longitudinal wave is fast, shear wave velocity is slow, and stretching ripple and torsional wave to be loaded on test specimen to people simultaneously and to bring very large difficulty by this.Because there is velocity contrast in two ripples, Institutes Of Technology Of Taiyuan Zhao Longmao teaches and professor Wang Zhihua proposes at rod member that simultaneously real so release stretches and the mode of reversing pre-energy storage produces and stretches and torsion load pulses near test specimen place, because arriving test specimen apart from short, the mistiming that velocity contrast causes can be thought in experimental error.But the greatest drawback of this method is difficult to record the incident wave loaded and the reflection wave be reflected back from test specimen.And these two ripples have recorded the important information of experiment, it is raw data indispensable when data processing carried out to experimental result.
Summary of the invention
The object of the invention is to the defect overcoming prior art, provide one dynamically to draw/press and turn round synchronization combining loading experimental apparatus, the incident wave that simultaneously can record loading and the reflection wave be reflected back from test specimen.
Technical matters to be solved by this invention realizes by the following technical solutions:
One is dynamically drawn/is pressed and turns round synchronization combining loading experimental apparatus, comprise and be arranged on transmission bar on rolling support and incident bar, between transmission bar and incident bar, test specimen is installed, it is characterized in that: described incident bar is provided with torsional wave charger and stretching/compressing ripple charger, the distance that described stretching/compressing ripple charger and incident bar install test specimen end is greater than the distance that torsional wave charger and incident bar install test specimen end, and described stretching/compressing ripple charger is connected with controller by signal circuit respectively with torsional wave charger.
Described stretching/compressing ripple charger comprises wave of compression charger and stretching ripple charger two kinds.To be stretched as example, described stretching ripple charger comprises stretching power valve, is arranged on the stretching bullet in stretching power valve and clashes into plug, also comprise the stretching transmitter be arranged on the left of stretching bullet and the absorption tube being arranged on shock plug right side, in stretching power valve, be also provided with trigger sensor.
Described wave of compression charger is slightly different from stretching ripple charger, and wave of compression charger is independent of incident bar.
Described torsional wave charger comprises rotation loading disc and clamps and instantaneous relase device, clamping and instantaneous relase device are arranged on test specimen and rotate between loading disc, determine release time needed for the compressional wave of bar material and transverse wave speed and releasing means from test specimen distance.
Described controller is trigger pip collection and instantaneous relase controller, and controller connects the trigger sensor of stretching/compressing ripple charger by signal circuit, and controller connects clamping and the instantaneous relase device of torsional wave charger by signal circuit.
Described controller is that stretching/compressing load pulses produces and reverses pre-energy storage instantaneous relase controller, and controller connects stretching/compressing ripple charger by signal circuit and reverses pre-energy storage instantaneous relase device.
To be stretched as example, the stretching bullet that stretching transmitter is launched moves to shock plug direction and clashes into plug in the hollow cavity (stretching power valve) of incident bar, produces a tensile stress wave and provide the pre-energy storage instantaneous relase controller one of torsion to trigger electric signal in incident bar.Described controller, after receiving above-mentioned triggering electric signal, can discharge clamping and instantaneous relase device (discharge required time differ be no more than 20 microseconds) fast in hundreds of gsec at every turn, thus discharges torsional energy formation distorting stress ripple.Described clamping and instantaneous relase device are that a hydraulic pressure encircling type is locked and releasing mechanism.Described trigger pip collection and instantaneous relase controller can adjust and clamp with the concrete release time of instantaneous relase device to ensure that tensile stress wave and distorting stress ripple arrive test specimen simultaneously.
Provided by the inventionly dynamically draw/press and turn round synchronization combining loading experimental apparatus, for material dynamic mechanical performance study, existing Hopkinson can be made up draw/the defect that combines of depression bar and torsion bar, can realize loading stretching/compressing ripple and torsional wave to test specimen simultaneously, make the stretching/compressing ripple of loading and torsional wave reach test specimen simultaneously, the incident wave that simultaneously can also record loading and the reflection wave be reflected back from test specimen, to meet the requirement of experimental study material dynamic mechanical performance.
Accompanying drawing explanation
Fig. 1 is structural representation of the present invention.
Wherein, 1. rolling support; 2. transmission bar; 3. test specimen; 4. incident bar; 5. torsional wave charger; 6. stretching ripple charger; 7. controller; 51. clampings and instantaneous relase device; 52. rod member pretwist sections; 53. rotate loading disc; 61. stretching transmitters; 62. stretching bullets; 63. stretching power valves; 64. trigger sensors; 65. clash into plug; 66. absorption tubes.
Embodiment
The technological means realized to make the present invention, creation characteristic, reaching object and effect is easy to understand, below in conjunction with specific embodiments and the drawings, setting forth the present invention further, but not being used to limit the scope of the invention.
As shown in Figure 1, one is dynamically drawn and is turned round synchronization combining loading experimental apparatus, comprise and be arranged on transmission bar 2 on rolling support 1 and incident bar 4, test specimen 3 is installed between transmission bar 2 and incident bar 4, incident bar 4 is provided with torsional wave charger 5 and stretching ripple charger 6, the distance that stretching ripple charger 6 and incident bar 4 install one end of test specimen 3 is greater than the distance that torsional wave charger 5 and incident bar 4 install one end of test specimen 3, and stretching ripple charger 6 is connected with controller 7 by signal circuit respectively with torsional wave charger 5;
Stretching ripple charger 6 comprises stretching power valve 63, is arranged on the stretching bullet 62 in stretching power valve 63 and clashes into plug 65, also comprise the stretching transmitter 61 be arranged on the left of stretching bullet 62 and the absorption tube 66 be arranged on the right side of shock plug 65, also be provided with trigger sensor 64 in stretching power valve 63, the moment that trigger sensor 64 clashes into plug 65 at stretching bullet 62 sends triggering electric signal to controller 7;
Torsional wave charger 5 comprises rotation loading disc 53 and clamps and instantaneous relase device 51, clamping and instantaneous relase device 51 are arranged on the side near test specimen 3, and rotating loading disc 53 with the incident bar section between clamping and instantaneous relase device 51 is rod member pretwist section 52;
Controller 7 is trigger pip collection and instantaneous relase controller, controller 7 connects the trigger sensor 64 of stretching/compressing ripple charger 6 by signal circuit, controller 7 connects clamping and the instantaneous relase device 51 of torsional wave charger 5 by signal circuit, after controller 7 receives the trigger pip that trigger sensor 64 sends, control clamping and discharge torsional wave with instantaneous relase device 51, the release of torsional wave comparatively receives trigger pip and postpones to some extent, ensure that torsional wave and stretching/compressing ripple arrive test specimen simultaneously, the time of delay is pre-set by calculating.
After Preparatory work of experiment work is ready, adjust controller 7 delay time, test specimen 3 is installed, then clamping and instantaneous relase device 51 is utilized to lock rod member pretwist section 52, hydraulic-driven rotates loading disc 53 makes rod member pretwist section 52 produce torsional deflection, and storage torsional energy, starts stretching transmitter 61, stretching bullet 62 moves to shock plug 65 under gases at high pressure effect, sends one and trigger electric signal while shock.This impinges upon in stretching power valve 63 and produces a tensile stress wave simultaneously and thoroughly enter incident bar 4 and move to test specimen direction.Controller 7 is after receiving above-mentioned triggering electric signal, and release clamping and instantaneous relase device 51 within the time of setting, the torsional strain of rod member pretwist section 52 storage can obtain release and in incident bar 4, form distorting stress wave direction test specimen 3 direction and propagate.Because clamping and instantaneous relase device 51 work by precalculating the time (i.e. above-mentioned delay time) obtained, thus can ensure that the distorting stress ripple (torsional wave) of rear generation arrives test specimen to reach the target setting of this device with the tensile stress wave (stretching ripple) previously produced simultaneously.
The present invention solves the problem that stretching pulse and torsional pulses are difficult to arrive test specimen simultaneously preferably.
More than show and describe the present invention for the ultimate principle, principal character and the advantage of the present invention that stretch with reverse synchronization combining and load, as compression with reverse that combination loading can according to present principles and this embodiment be convenient realize.The technician of the industry should understand; the present invention is not restricted to the described embodiments; what describe in above-described embodiment and instructions is only preference of the present invention; be not used for limiting the present invention; without departing from the spirit and scope of the present invention; the present invention also has various changes and modifications, and these changes and improvements all fall in the claimed scope of the invention.Application claims protection domain is defined by appending claims and equivalent thereof.
Claims (3)
1. one kind is dynamically drawn/presses and turns round synchronization combining loading experimental apparatus, comprise and be arranged on transmission bar on rolling support and incident bar, between transmission bar and incident bar, test specimen is installed, it is characterized in that: described incident bar is provided with torsional wave charger and stretching/compressing ripple charger, the distance that described stretching/compressing ripple charger and incident bar install test specimen end is greater than the distance that torsional wave charger and incident bar install test specimen end, and described stretching/compressing ripple charger is connected with controller by signal circuit respectively with torsional wave charger.
2. according to claim 1ly dynamically draw/press and turn round synchronization combining loading experimental apparatus, it is characterized in that: described torsional wave charger comprises rotation loading disc and clamps and instantaneous relase device, clamping and instantaneous relase device are arranged between test specimen and rotation loading disc.
3. according to claim 1ly dynamically draw/press and turn round synchronization combining loading experimental apparatus, it is characterized in that: described controller is trigger pip collection and instantaneous relase controller, controller connects the trigger sensor of stretching/compressing ripple charger by signal circuit, and controller connects clamping and the instantaneous relase device of torsional wave charger by signal circuit.
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| CN201510106511.6A CN104729918B (en) | 2015-03-11 | 2015-03-11 | Dynamic pull/pressing and torsion synchronous combined loading experiment device |
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| CN201510106511.6A CN104729918B (en) | 2015-03-11 | 2015-03-11 | Dynamic pull/pressing and torsion synchronous combined loading experiment device |
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| CN104729918B CN104729918B (en) | 2017-05-24 |
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Cited By (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106018099A (en) * | 2016-06-22 | 2016-10-12 | 国网河南省电力公司电力科学研究院 | System and method for detecting crimping quality of end fitting of composite insulator |
| CN108120647A (en) * | 2017-12-18 | 2018-06-05 | 宁波大学 | A kind of material impact reverses loading experimental apparatus |
| CN108387447A (en) * | 2018-02-08 | 2018-08-10 | 合肥姜水材性科技有限公司 | A kind of electromagnetic type is drawn, pressure turns round Microsecond grade synchronization combining dynamic load experimental provision |
| CN108519296A (en) * | 2018-03-27 | 2018-09-11 | 西北工业大学 | A kind of dynamic mechanics parameter of material acquisition device and method |
| CN108519283A (en) * | 2018-03-27 | 2018-09-11 | 西北工业大学 | A kind of dynamic mechanics parameter of material acquisition device and method |
| CN109708971A (en) * | 2019-01-16 | 2019-05-03 | 浙江大学 | A kind of pulling and pressing integrated experimental rig of Hopkinson |
| CN110411862A (en) * | 2018-04-28 | 2019-11-05 | 西北工业大学 | Test device and test method for torsion mechanical property of the test material under middle strain rate |
| CN111044352A (en) * | 2019-12-31 | 2020-04-21 | 太原理工大学 | Separated Hopkinson bar pressure and torsion load composite loading device and use method thereof |
| CN111044353A (en) * | 2019-12-31 | 2020-04-21 | 太原理工大学 | Split Hopkinson bar tension-torsion load composite loading device and using method thereof |
| CN111398072A (en) * | 2019-01-21 | 2020-07-10 | 西北工业大学 | Dynamic uniaxial bidirectional asynchronous loading device and method thereof |
| WO2021043195A1 (en) * | 2019-09-06 | 2021-03-11 | 西北工业大学 | Composite loading device for compressive/tensile stress wave-torsional stress wave |
| CN112945726A (en) * | 2021-01-29 | 2021-06-11 | 太原理工大学 | Split Hopkinson bar pulling/pressing-twisting dynamic composite loading device and operation method |
| CN114152505A (en) * | 2021-11-24 | 2022-03-08 | 哈尔滨瞬态加载试验设备技术开发有限公司 | Stress reversal dynamic tensile loading test system |
| CN114878355A (en) * | 2022-05-07 | 2022-08-09 | 天津大学 | Friction test device based on Hopkinson torsion bar |
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Cited By (20)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106018099B (en) * | 2016-06-22 | 2019-07-12 | 国网河南省电力公司电力科学研究院 | A method of for detecting end part of composite insulator fitting crimp quality |
| CN106018099A (en) * | 2016-06-22 | 2016-10-12 | 国网河南省电力公司电力科学研究院 | System and method for detecting crimping quality of end fitting of composite insulator |
| CN108120647A (en) * | 2017-12-18 | 2018-06-05 | 宁波大学 | A kind of material impact reverses loading experimental apparatus |
| CN108120647B (en) * | 2017-12-18 | 2020-01-31 | 宁波大学 | material impact torsion loading experimental device |
| CN108387447A (en) * | 2018-02-08 | 2018-08-10 | 合肥姜水材性科技有限公司 | A kind of electromagnetic type is drawn, pressure turns round Microsecond grade synchronization combining dynamic load experimental provision |
| CN108519296A (en) * | 2018-03-27 | 2018-09-11 | 西北工业大学 | A kind of dynamic mechanics parameter of material acquisition device and method |
| CN108519283A (en) * | 2018-03-27 | 2018-09-11 | 西北工业大学 | A kind of dynamic mechanics parameter of material acquisition device and method |
| CN110411862A (en) * | 2018-04-28 | 2019-11-05 | 西北工业大学 | Test device and test method for torsion mechanical property of the test material under middle strain rate |
| CN109708971A (en) * | 2019-01-16 | 2019-05-03 | 浙江大学 | A kind of pulling and pressing integrated experimental rig of Hopkinson |
| CN111398072B (en) * | 2019-01-21 | 2023-01-17 | 西北工业大学 | Dynamic uniaxial bidirectional asynchronous loading device and method thereof |
| CN111398072A (en) * | 2019-01-21 | 2020-07-10 | 西北工业大学 | Dynamic uniaxial bidirectional asynchronous loading device and method thereof |
| WO2021043195A1 (en) * | 2019-09-06 | 2021-03-11 | 西北工业大学 | Composite loading device for compressive/tensile stress wave-torsional stress wave |
| CN111044353A (en) * | 2019-12-31 | 2020-04-21 | 太原理工大学 | Split Hopkinson bar tension-torsion load composite loading device and using method thereof |
| CN111044352B (en) * | 2019-12-31 | 2022-02-15 | 太原理工大学 | Separated Hopkinson bar pressure and torsion load composite loading device and use method thereof |
| CN111044353B (en) * | 2019-12-31 | 2022-02-15 | 太原理工大学 | Split Hopkinson bar tension-torsion load composite loading device and using method thereof |
| CN111044352A (en) * | 2019-12-31 | 2020-04-21 | 太原理工大学 | Separated Hopkinson bar pressure and torsion load composite loading device and use method thereof |
| CN112945726A (en) * | 2021-01-29 | 2021-06-11 | 太原理工大学 | Split Hopkinson bar pulling/pressing-twisting dynamic composite loading device and operation method |
| CN112945726B (en) * | 2021-01-29 | 2022-06-07 | 太原理工大学 | Split Hopkinson bar pulling/pressing-twisting dynamic composite loading device and operation method |
| CN114152505A (en) * | 2021-11-24 | 2022-03-08 | 哈尔滨瞬态加载试验设备技术开发有限公司 | Stress reversal dynamic tensile loading test system |
| CN114878355A (en) * | 2022-05-07 | 2022-08-09 | 天津大学 | Friction test device based on Hopkinson torsion bar |
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