A temperature compensating device used for a real-time low-temperature split Hopkinson pressure bar test

Abstract

The invention relates to a temperature compensating device used for a real-time low-temperature split Hopkinson pressure bar test. The device includes a low-temperature environment box, a low-temperature liquid nitrogen cylinder and a gas pressure pump. Liner walls of a box body and a door of the low-temperature environment box are provided with a heat insulation material. The top of the box bodyis provided with a liquid nitrogen feeding pipe, and symmetrical two side walls of the box body are provided with bar holes respectively. The door is provided with an observation window. The liquid nitrogen feeding pipe communicates with a liquid nitrogen discharging pipe extending into the inner bottom of the low-temperature liquid nitrogen cylinder. A gas outlet of the gas pressure pump communicates with an air feeding pipe of the low-temperature liquid nitrogen cylinder through a gas pipe. When in use, the low-temperature environment box is firstly mounted on a cross beam of a split Hopkinson pressure bar test device, then test piece clamping ends of an incident bar and a transmission bar of the split Hopkinson pressure bar test device are stuck into the box body through the bar holes at left and right sides of the box body respectively, and then a test piece is clamped between the clamping ends of the incident bar and the transmission bar. The working temperature range of the temperature compensating device ranges from room temperature to -100 DEG C, an outer shell of the box body is free of a sweating phenomenon, and test piece fragments are effectively prevented from flying out during impact in an SHPB test.

Description

technical field [0001] The invention belongs to the technical field of a test device for testing the dynamic mechanical properties of materials at low temperature, and in particular relates to a Split Hopkinson Pressure Bar test device (Split Hopkinson Pressure Bar, referred to as SHPB). Background technique [0002] The separated Hopkinson strut stems from a strut designed by the British scholar B. Hopkinson in 1914, reconceived by Davis and Kolsky around 1949, and continuously improved by many researchers later. Today, the combination of split Hopkinson pressure rods with high-speed photography, optomechanical speckle technology and finite element dynamic numerical simulation has become an indispensable and powerful tool for mechanics and material scientists to develop new materials. The separated Hopkinson pressure bar uses the stress wave generated by high-speed impact to study the dynamic mechanical properties of materials. 2 ~10 4 the s -1 The stress-strain relation...

AI Technical Summary

Problems solved by technology

At present, people use the SHPB test device to carry out dynamic mechanical test research on materials at room temperature or high temperature, but there are certain difficulties in using the SHPB test device to carry out material test research in real-time low temperature environments.

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