Split Hopkinson pressure bar (SHPB) test system ALT1000
——Built in dynamic stress-strain analysis software to provide external testing services
1、 Brief intbaruction of split Hopkinson pressure bar (SHPB) ALT1000
Hopkinson bar is an effective experimental device to study the dynamic mechanical properties of materials under one-dimensional stress state. It can directly test the stress and strain of samples under dynamic impact state. Since Kolsky invented it in 1949 and used it to study the dynamic mechanical properties of materials under one-dimensional stress state, the experimental device has been improved a lot and the experimental technology has been improved continuously. The device tests the strain of the specimen when it is impacted by the dynamic shock wave through the uniform transmission of the stress wave, and calculates the corresponding parameters such as strain rate, stress, strain energy, incident energy, transmission energy, reflection energy, particle impact velocity and high g value according to the experimental parameters. Application: it can test dynamic properties of sand, concrete, reinforced concrete, metal and non-metallic foam, composite and polymer materials at high strain rates. It can also be used to test the dynamic performance of the sample under different peripheral constraints. Loading mode: pneumatic or electromagnetic Maximum diameter of sample: 100mm Strain rate: 1000 / S ~ 20000 / S Standard pole to be used: 4-100mm (one set of equipment can be equipped with 2-3 sets of poles of different specifications at the same time) Control mode: double safety switch, pneumatic control Pressurization method: air compressor (high pressure nitrogen optional) Heating mode: PID temperature control, with water cooling system (optional) Cooling method: liquid nitrogen or alcohol (optional) Bullet speed measurement: laser speed measurement system (optional) Confining pressure and axial pressure: hydraulic full-automatic pressure system (optional) Tailstock buffer: mechanical or liquid gas combined buffer It can be used in the analysis and test of other dynamic impact mechanics Meet the national standard: GBT 34108-2017 metallic materials high strain rate room temperature compression test method
2、 Superior performance of SHPB alt1000
Alt1000 adopts the cabinet structure design, and directly installs the launch system and the pull bar system between the two operating consoles. All the spare parts are installed inside the workbench, which is neat, beautiful and practical. The launch and control system is installed in the front console, the operator can complete the operation of bullet launch and bullet recovery data processing in front of the computer, which is very convenient. The high temperature heating system and synchronous cylinder are installed in the rear console, and the target temperature can be adjusted at will through the PID control system. The water cooling system is installed outside the high temperature furnace to ensure the safety of operation. Each bar system can be installed on the same specification support platform through different diameter bar sleeve with bearing, and the pressing bar can be replaced at will. The same system can also be equipped with two sets of bases to adapt to the bar diameter of different diameters. Through the system adjustment of the bar and the launching system, the equipment can impact the classic regular square wave.
1. It can change the diameter of different bars quickly: adopt the diagonal compression bar support, in a Huo set, it is convenient to realize all kinds of Huo bar tests by changing the barrel, achieve all kinds of experimental purposes, and save money for users.
2. The main body is designed with cabinet structure and profile steel track, which has strong practicability, convenient operation and appearance in line with modern industrial aesthetic concept.
3. The pull bar and pressure bar can share a main body, a collection system and a gas chamber emission system. The pull bar bracket adopts a bearing bracket, which is convenient for installation and sliding.
4. The operation panel is integrated on the cabinet behind the gun barrel to ensure the operation safety. The impact bar can be automatically launched and returned to its original position. Double opening and closing are adopted to avoid misfiring.
5. Eliminate the external electromagnetic interference and prevent the acquisition system from triggering by mistake. The launch control system adopts pneumatic control system. 6. The data acquisition software can select the start and end points of the waveform at will, and can select any band data for analysis.
7. The data processing software automatically identifies the take-off points of the transmitted and reflected waves, automatically calculates the stress, strain, strain rate, strain energy, incident energy, transmission energy, reflection energy, particle impact speed, automatically generates the stress-strain curve, as well as the curve of time and above parameters, and can calculate the square sample. The above functions can be demonstrated on site.
8. Unified benchmark: the segmented combined guide rail assembled by proprietary technology can be arbitrarily lengthened or shortened, with high-precision horizontal and plane unified benchmark, which can make the launching system (including various gun tubes) and bar system (various bar diameters) debug and install at any position under the same benchmark, greatly saving debugging time, convenient operation and improving test accuracy.
9. Standard modularity: no matter the launch system, central support device or guide rail, all adopt standard modular structure. No matter what kind of pull bar test equipment you need, you can meet the test requirements by increasing or decreasing the number, which is easy to promote.
10. Expansibility: the system has strong expansibility. It can be tested under various conditions, such as speed measurement, high temperature, confining pressure, three-point bending, shearing, etc., and an auxiliary equipment (high-precision grinding head frequency conversion power drive, short linear guide pair, bar rotating power mechanism, etc.) can be added to the guide rail to solve the problem of long bar grinding; it is easy to be realized without adding any test items, such as single loading device for various diameter bars Now, the buffer device can be shifted, etc.
The data processing software of Hopkinson pull bar can automatically identify the jumping point and the ending point of the transmitted and reflected waves, and can also identify manually. At the same time, it can test the square sample, and calculate the impact stress-strain, strain energy, particle velocity, reflection energy, transmission energy and other data of the sample. It is simple to operate and convenient to use. According to the first-class level of the current industry. Hopkinson multi-functional pull bar equipment mainly consists of air storage device, launch and control control system, bar system and bullet, measurement and analysis system, center support component, combined foundation guide rail, active confining pressure part, single loading device, buffer device and auxiliary equipment. Hopkinson multi-functional pull and pull equipment is a set of special test equipment based on a unified high-precision benchmark.
Rod diameter: Φ 100, Φ 80, Φ 75, Φ 70, Φ 50, Φ 37, Φ 30, Φ 20, Φ 18, Φ 16, Φ 14.5, Φ 12, Φ 10, Φ 8, Φ 4, etc. A set of equipment can be equipped with multiple sets of bar systems, and the bar and bar can be installed in the same main body, sharing the acquisition system and gas drive system; Rod system and bullet: the material is 18Ni, spring steel, titanium and other high-strength steel; the metal materials are overheated, and the perpendicularity of all bar end faces can be within 0.02, and the bar diameter and end face roughness can be above Ra0.8.
3、 Alt1000 data acquisition system of SHPB 1. Equipment function intbaruction and main technical indexes: Alt1000 ultra dynamic data acquisition system is specially used for the test and analysis of hobkinson bar experiment. The highest transient sampling rate of the system is 40MHz, each channel is independent of a / D analog-to-digital converter, and the external strain conditioner completes the stress-strain test and analysis of 1 / 4 bridge, half bridge and full bridge states. The system has the functions of real-time acquisition, real-time display, real-time storage and real-time analysis of the measured signal, automatic test control and data waveform analysis and processing. Alt1000 ultra dynamic data acquisition system has the functions of software trigger, internal trigger, external trigger and positive and negative delay. The highest A / D conversion rate is 40msps. Press down 1, 2 and 5 to divide the frequency. Bnc coaxial cable (differential connector can be selected) is used for signal input. The maximum storage depth of sampling in each channel is 8msa, and the sampling length can be set at will by software. The system is equipped with system driver control program software, which runs on Windows XP / 7 operating platform. The control panel is completely virtual instrument soft panel, and the graphical interface is very friendly.
4、 Brief intbaruction of alt1000 software of SHPB
Main functions The data analysis software of Hopkinson compression bar, developed by Archimedes industrial technology company, has very powerful functions. It can calculate the dynamic compression, tension, torsion, bending, shear and other items at the same time, and obtain the data of dynamic stress, strain, strain rate, strain energy, incident energy, transmission energy, reflection energy, particle velocity, high g value and sample temperature rise
Main operation interface of ALT1000
Automatically move the wave, intercept the wave and calculate the result automatically
Dynamic stress-strain curve
Strain rate 1/S
Instant temperature rise of impact specimen (° C)
Test results (strain rate, stress strain, strain energy, transmission energy, reflection energy, reflection energy, particle velocity, high g value, instantaneous temperature)
High g value
Conservation of energy (incident energy = strain energy + reflection energy + transmission energy)
Operation console and heating system (patent design: Bullet automatic launch recovery system)
Large diameter compression bar (100mm in diameter, with environmental coupling system such as automatic confining pressure and axial pressure heating)