A method for continuous measurement of crack front opening type sif in a three-dimensional volume
A technology of internal cracks and crack fronts, which is applied in the direction of measuring devices, testing of mechanical components, testing of machine/structural components, etc., can solve problems such as inability to continuously measure SIF of internal crack fronts in three-dimensional bodies, and achieve convenient testing and calculation The effect of small workload and simple experimental optical path
Inactive Publication Date: 2019-03-29
BEIHANG UNIV
View PDF4 Cites 0 Cited by
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Problems solved by technology
[0006] The technical problem of the present invention is: to overcome the deficiency in the prior art that the SIF of the crack front inside the three-dimensional body cannot be continuously measured, and to provide a continuous measurement method for the crack front opening type SIF inside the three-dimensional body
Method used
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View moreImage
Smart Image Click on the blue labels to locate them in the text.
Smart ImageViewing Examples
Examples
Experimental program
Comparison scheme
Effect test
Embodiment Construction
[0035] The present invention will be further described below in conjunction with the accompanying drawings.
[0036] Such as figure 1 As shown, the present invention provides a continuous measurement method for the open type SIF of a crack front in a three-dimensional body, which method includes: making internal cracks in a three-dimensional body model, loading and stress freezing, processing and retaining the stress singularity region of the internal crack front, There are six implementation steps: displaying the deformation of the three-dimensional crack front through stress release, obtaining continuous images of the open SIF of the three-dimensional crack front by the caustic method, and quantitatively determining the value of the open SIF. in:
[0037] Step 1: Making cracks inside the 3D model
[0038] A three-dimensional model of epoxy resin with internal semicircular cracks is made by pre-embedding method; epoxy resin material is a kind of high molecular polymer, whic...
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More PUM
Login to View More Abstract
The invention provides a three-dimension body inside crack front edge opening type SIF continuous measuring method. According to the method, a three-dimension epoxy resin model with inside cracks is subjected to temperature rise and constant-temperature treatment, loading and temperature lowering treatment, so that the special deformation of the three-dimension crack front edge is cured; through mechanical processing, the three-dimensional crack surfaces are removed; only the foundation part including the crack front edge root parts inside the epoxy resin model is remained; the remained crack root part is subjected to polishing treatment, so that the remained crack root part becomes a mirror surface reflecting surface; then, the temperature rise, temperature maintaining and temperature lowering treatment processes are performed to realize the stress release of the three-dimension body crack front edge part; the three-dimension crack front edge part generates the deformation in an opposite direction to that during the loading; then, beam collecting light is used for illuminating the strain special region of the three-dimension body crack front edge part to obtain a continuous caustic image along the three-dimension crack front edge; through the measurement and the calculation on the feature parameters of the caustic image, the continuous quantity measurement of the three-dimension body inside crack front edge opening type SIF value can be realized.
Description
technical field [0001] The invention relates to a continuous measurement method of an SIF opening type crack front in a three-dimensional body, which belongs to the field of experimental solid mechanics. Background technique [0002] The presence and subsequent growth of cracks in mechanical components and structural parts can lead to serious accidents. In order to determine the strength of structures and parts, SIF (stress intensity factor) has been effectively applied to various fracture mechanics problems as a measure of the stress field size in high-stress areas near the crack tip. SIF is a very important parameter in structural safety design . [0003] The theoretical calculation and experimental testing methods of two-dimensional crack SIF have been relatively mature. However, most of the actual structures are three-dimensional structures, and cracks and defects are often located inside the three-dimensional bodies. Therefore, it is very important to determine the S...
Claims
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More Application Information
Patent Timeline
Login to View More Patent Type & Authority Patents(China)
IPC IPC(8): G01N3/18G01M13/00
CPCG01M13/00G01N3/18G01N2203/0067
Inventor 商兰吴大方王怀涛
Owner BEIHANG UNIV