Visual dynamic stress-strain testing system alt1800

——Built in dynamic stress-strain analysis software to provide external testing services

1、 A brief intbaruction to ultra high speed visualization Compared with the previous method of directly measuring the object under study, we can now use high-speed camera and related professional software to carry out optical measurement, including measuring the deformation, displacement and strain of materials and other information. This new technology is called digital image correlation (DIC). With the rapid development of this technology, it has been widely used in many fields, such as aerospace, national defense and automobile industry. In the analysis of digital image correlation technology, it is necessary to apply the speckle field to the object to be detected first. After applying the stress, the camera and digital image correlation technology software will record and analyze the movement of the speckle field to reveal the area where the strain and displacement occur. The analysis operation of DIC can be completed by using single or multiple synchronous cameras, but these cameras need to have the function of recording at different angles. A single camera will obtain a two-dimensional image, which can be used to analyze the elongation, tensile strength and single plane distortion of materials. However, many camera systems are more common. This system can obtain three-dimensional images and can be used for plane vibration and distortion analysis. No matter which type of DIC device you choose, this technology is superior to the traditional sensor method. DIC is a non-contact method, which is a key feature advantage compared with sensor technology, because sensor technology will change the displacement or deformation information of objects, and DIC technology can provide more discrete data points than sensor technology. In addition, DIC technology analysis is faster, cheaper, and easy to integrate with other technologies. 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: 50mm 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 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 transmitted and reflected waves, automatically calculates the stress, strain, strain rate, strain energy, incident energy, transmission energy, reflection energy, particle impact velocity, automatically generates the stress-strain curve, as well as the curve of time and above parameters

3、 Technical parameters of super high speed camera With a unique 1280 × 800 CMOS sensor, the full frame shooting rate is 7400 frames / second, and the maximum shooting rate can reach 1000000 frames / second (optional); with ultra-high sensitivity (ISO): 40000 (black and white); 10000 (color). The time precision of 20ns makes it have higher frame rate, frame synchronization and exposure precision; the minimum time interval of 395ns two exposures can meet the needs of PIV / PTV / LIF / DIC application without image lag; EDR exposure control can set two kinds of exposure time in one frame of image, effectively avoiding the influence of glare and strong light on image during explosion; the maximum storage capacity is 256gb, meeting the requirement of long-time recording Required: 3G HD-SDI and standard HDMI video output can be connected to analog and digital monitors to display captured images in real time. 1 million pixel image pbaruct frame rate: 1280 × 800 @ 7400 frames / second (7gpx / s) Maximum shooting rate: 680000 FPS (standard); 1000000 FPS (optional) Minimum exposure time: 1 μ s (standard); 300ns (optional) Ultra high sensitivity (ISO): 40000 (black and white); 10000 (color) Memory capacity: 18gb / 36gb / 72gb

Visual impact test of coal with confining pressure

4、 Visual high speed camera software for stress and strain calculation

Super high speed camera (carbon fiber impact video)