Standard Prestressing Apparatus for Verification of Residual Stress Indentation Test Method

Abstract

The invention discloses a standard prestress loading device applied to a residual stress press-in test method detection. The device comprises a matrix, a loading element, a digital display force sensor and a fixture. Holes are respectively arranged on both ends of the matrix. The holes on left and right ends are concentric. A boss supporting a sample is arranged in the matrix. The digital display force sensor comprises a force sensor and a force display, wherein the force sensor and the force display are connected. The force sensor is arranged in the matrix, and is respectively connected with the loading element and the fixture. The loading element is connected with the force sensor through the hole on the left end of the matrix, and is used for applying axial compression or tension on the sample. The fixture is located in the matrix, is used for clamping the sample along the axial direction, and is fixed with the matrix through the hole on the right end of the matrix. According to the invention, the device has the advantages of simple structure, uniform prestress distribution, and direct and accurate measurement; in a press-in test process, the prestress state is stable, and the value is not affected by a press-in experiment; and the device can be used as a standard prestress generation device.

Description

technical field [0001] The invention relates to the field of testing devices for mechanical properties of materials, in particular to a standard prestressed loading device used for the inspection of residual stress compression test methods. Background technique [0002] The existence of residual stress in engineering materials will change the service stress environment of components and cause unexpected failure. Therefore, the detection of material residual stress has become a mechanical problem of great concern in the field of engineering applications. Traditional methods for detecting residual stress can be roughly divided into two categories: mechanical testing methods and physical testing methods. The mechanical test method uses mechanical methods to partially divide the specimen to release the residual stress. By measuring the deformation before and after the division, the residual stress is determined based on the theory of elastic mechanics. This type of test method ...

AI Technical Summary

Problems solved by technology

[0006] The technical problem to be solved by the present invention is to overcome the fact that the loading device in the prior art forms bending stress in the test area of ​​the specimen by bending, and the prestress is different at different pressing positions, and the measurement of the prestress at the pressing position needs to be combined. Complicated force analysis and position measurement have the defects of indirect measurement cumulative error, which cannot directly provide accurate and reliable prestress value. A standard prestress loading device for the inspection of residual stress indentation test method is proposed, which can be used on the sample The ideal and uniform uniaxial tension (compression) prestress can be produced in the middle, and the standard reference stress can be provided for the research of residual stress indentation test method

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