High-temperature hopkinson rod tensile test device and method capable of precise quantitative electromagnetic control

Abstract

The invention relates to a high-temperature Hopkinson rod tensile test device and method capable of precise and quantitative electromagnetic control. Three sets of high-precision delayers, one set of electromagnetic push rod system and one set of electromagnetic The dragging system, using the electromagnetic push mechanism and high-precision time-delay device, can accurately control the start and end time of each step in the high-temperature dynamic tensile test, including the impact generation process, sample movement and loading rod assembly process, loading rod movement process, and the entire test process. The cold contact time can accurately and directly test the dynamic mechanical properties of materials at high temperatures. The device has a high degree of integration and is easy to operate. It standardizes the empirical operation process of the traditional Hopkinson high-temperature tensile test method, has a high degree of automation, avoids the problem of poor repeatability of pneumatic control, and greatly improves the accuracy of high-temperature dynamic tensile tests.

Description

technical field [0001] The invention belongs to a Hopkinson rod tensile test device, and relates to a high-temperature Hopkinson rod tensile test device and method capable of precise quantitative electromagnetic control. Background technique [0002] As materials are used in more and more fields, especially in the aerospace industry, materials are often exposed to extreme working environments with high temperature and high strain rates. Therefore, determining the dynamic mechanical properties of materials in high temperature environments is a constant issue for mechanics and materials professionals. major issues of concern. The separate Hopkinson rod technology is the most important method to test the dynamic mechanical properties of materials. How to accurately test the dynamic properties in high temperature environment has become an urgent problem to be solved in the development of Hopkinson rod technology. [0003] The main difficulty in carrying out high-temperature ten...

AI Technical Summary

Problems solved by technology

It is difficult to precisely control the excitation time of the launch system and the synchronous assembly system by using the transfer time of the gas in the gas tube of different lengths, resulting in uncertainty and uncontrollability of the cold contact time

At the same time, the operation of the device is relatively complicated, the degree of integration and instrumentation is low, and it does not take advantage of the promotion and wide application of technology

[0005] Summarizing the current development status of high-temperature Hopkinson tensile test methods and devices, the main technical difficulties currently exist: 1) Since the tensile specimen in the separate Hopkinson tension rod is usually connected with the loading rod by thread, glue connection or pin connection, online The heating method will inevitably cause the temperature gradient field distribution in the loading rod and the sample, which will affect the accuracy of the test results

2) Although the correction of the temperature gradient field can reduce the influence of the temperature gradient on the accuracy of the data in the data processing after the test, it is an indirect processing method with errors, and at the same time, it cannot be stretched higher than the phase transition temperature of the loading rod. Test; 3) Pneumatic rapid synchronous assembly technology can directly obtain the dynamic tensile properties of materials at very high temperatures, but the precise control of the assembly process and loading process has not yet been achieved, and the level of device integration is low

The currently developed pneumatic synchronous assembly method has the problem that it is difficult to accurately control the assembly process and cold contact time, the operation method is difficult to quantify and standardize, and the degree of equipment instrumentation is low

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