Residual stress measurement system through hole-drilling method

Abstract

The invention discloses a residual stress measurement system through a hole-drilling method, and belongs to the technical field of material processing and experimental stress analysis. The system comprises two parts: a drilling device and stress calculation software. The drilling device is formed by a speed-adjustable electric hand drill, a tool microscope, a drill rod, a guide cylinder and a magnetic support base and the like; and the calculation software is programmed through C language, and can give residual stress in an assigned direction, or principal stress and included angle in real time. Since a drilling guide device adopts an embedded ball bearing mode, an rotary friction effect of the drill rod is totally prevented; since the support adopts permanent magnetic bases and lock nuts each having a breach, site positioning and fillet weld stress measurement are realized greatly; and since the calculation program takes features of change of hole edge plastic deformation and processing strain with the stress value into consideration, a stress calculation formula of any two vertical directions is given to enable welding residual stress measurement to become much easier and accurate.

Description

technical field [0001] The invention relates to the technical field of material processing and experimental stress analysis, in particular to a drilling method residual stress measurement system. Background technique [0002] Residual stress exists in most of the components manufactured by welding and other thermal processing processes. Higher values ​​of residual stress will have an adverse effect on the long-term safe use of components. Controlling and measuring residual stress has become a very important research and application direction. [0003] In structures such as welding, the method of drilling to measure residual stress has been widely used. The principle of the drilling method to measure the residual stress is to paste a three-way or two-way strain rosette on the measured part of the workpiece, and process a small blind hole of Φ1.5-3mm in the center of the strain rosette to cause the release of the residual stress. The stress- The release strain relationship ca...

AI Technical Summary

Problems solved by technology

At present, the common problems of low-speed equipment are: 1) The diameter of the drilling hole is fixed, and it is inconvenient to replace the chuck

2) The drill pipe is directly in contact with the positioning sleeve, which affects the drilling operation and the strain value of the drilling process

3) The calculation system of the system is not perfect, because the processing strain and the plastic deformation of the hole edge change with the stress, the error is large when testing the high stress field 4) The flexibility and convenience of the equipment on site are not enough

Patent 4 (Application No.: 200920105688.4; Invention Name: A Magnetic Full-Surface Drilling Device Using Blind Hole Method for Stress Measurement) mainly discloses a method for quickly fixing the surface of ferromagnetic materials, which has improved the test to a certain extent. The purpose of efficiency, but not suitable for non-ferromagnetic materials such as aluminum alloy

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