An experimental method for large deformation impact compression of materials

Abstract

The invention discloses a large-deformation shock compression experimental method for materials. The large-deformation shock compression experimental method is characterized in that the right end surface of a transmission bar is fixedly connected with a support block, and a piece to be tested is fixed on the left end surface of the transmission bar, and is in tight contact with the left end surface of the transmission bar; two strain gauges which are symmetrical along an axial center surface are fixed to the outer surface, close to the left end, of the transmission bar, an impact bar of which the material, the length and the diameter are all the same as those of the transmission bar is selected, and regulation is performed, so that the impact bar, the piece to be tested, and the transmission bar are coaxial; and then, the impact bar is emitted, the two strain gauges fixed to the transmission bar are used for testing strain signals of the transmission bar, the tested strain signals of the transmission bar are substituted to a relational expression, and treatment is performed, so that a time interval curve about the axial engineering stress, engineering strain and engineering strain rates, of the tested piece during an experiment is obtained. The large-deformation shock compression experimental method has the advantages that a continuous stable experiment strain rate is realized, and under the condition of the biggest strain same as a conventional Hopkinson pressure bar experiment, the strain rate can achieve the 10 S<-1> order.

Description

technical field [0001] The invention relates to an experimental method for testing the dynamic performance of materials, in particular to an experimental method for large deformation impact compression of materials. Background technique [0002] The mechanical properties of engineering materials under dynamic loading conditions are usually described by constitutive equations related to strain rate, and the difference in dynamic mechanical properties of materials is reflected by their constitutive parameters, while the constitutive parameters related to strain rate of materials cannot It is obtained by means of theoretical analysis and must be determined through material dynamic loading experiments. [0003] The separated Hopkinson pressure bar or Kolsky bar is the most widely used and considered effective experimental device for testing the mechanical properties of materials at high strain rates. It can be used to test various engineering materials at 10 2 ~10 4 S -1 Dyna...

AI Technical Summary

Problems solved by technology

However, the traditional Hopkinson compression bar can only achieve the experimental strain at a relatively high strain rate when the total length of the device is limited, and the 10S -1 It is impossible or difficult to achieve the desired deformation of the specimen under the magnitude of the strain rate

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