Metal fatigue crack full-life estimation method based on damage mechanics non-probabilistic interval analysis model

A technology of damage mechanics and fatigue cracks, applied in the field of fatigue fracture and damage mechanics, can solve the problems of limiting the application of random models, probability models that cannot truly describe objective reality, and lack of information

Inactive Publication Date: 2016-11-09
BEIHANG UNIV
View PDF3 Cites 25 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

In actual engineering, it is often expensive to obtain sufficient test data
As a result, the lack of information makes the probabil

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 more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Metal fatigue crack full-life estimation method based on damage mechanics non-probabilistic interval analysis model
  • Metal fatigue crack full-life estimation method based on damage mechanics non-probabilistic interval analysis model
  • Metal fatigue crack full-life estimation method based on damage mechanics non-probabilistic interval analysis model

Examples

Experimental program
Comparison scheme
Effect test

Embodiment

[0118] In order to describe the characteristics of this invention more fully, the present invention aims at image 3 The standard test piece model shown is based on the non-probabilistic interval analysis model of damage mechanics for metal fatigue crack life prediction. The material of the rectangular plate is LY12CZ aluminum alloy, the length, width and center hole diameter are 210mm, 100mm and 10mm respectively, and the load is 150MPa tensile stress. Finite element meshing such as Figure 4 As shown, the upper end is fixed and the lower end pressure is 150MPa. According to the content of step 3 of the appeal, the damage parameters and uncertain information are fitted with the data of the fatigue S-N curve as shown in Table 1 below.

[0119] Table 1

[0120]

[0121] Query the standard fatigue test manual. The fracture toughness of the standard parts corresponding to the thickness of 2mm is And it can be seen that the stress intensity factor is calculation, where ...

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

No PUM Login to view more

Abstract

The invention discloses a metal fatigue crack full-life estimation method based on a damage mechanics non-probabilistic interval analysis model. The method comprises the following steps: firstly, selecting a damage evolution equation from a damage mechanics model to establish a finite element analysis formation which structurally comprises damage information, and inquiring a fatigue test manual to fit to obtain a parameter in the damage evolution equation; then, combining with a damage mechanics finite element method with an interval finite element method to regard an initial damage degree and a damage parameter as interval uncertainty variables to represent fatigue life dispersivity; further, establishing the finite element analysis model of the structure, giving an initial critical element damage degree increment, constantly carrying out iteration increase on the damage degrees of all elements, judging that the element is damaged through the damage degree of each element, and endowing with intensity and rigidity attributes; and finally, when crack expansion achieves critical crack length, judging that the structure is damaged, and calculating to obtain a fatigue life range via a damage evolution equation variant and an interval vertex propagation analysis method. By use of the metal fatigue crack full-life estimation method, the life of the fatigue crack can be more elaborately estimated.

Description

technical field [0001] The present invention relates to the field of fatigue fracture and damage mechanics, in particular to the quantitative characterization of structural safety performance by crack growth scale under the influence of uncertainty and the refined analysis of fatigue crack full life based on the combination of damage mechanics finite element and non-probability interval finite element . Background technique [0002] With the development of science and technology, the design idea of ​​structure has experienced the evolution of static strength, dynamic strength, fatigue strength and fracture strength. Since the emergence of damage mechanics, it has become a new trend to use damage mechanics methods to study fatigue cracks. Damage mechanics is a relatively systematic study of micro-defects and the effects of these defects on stress and strain states. It is a new discipline in the field of solid mechanics, and its theoretical basis is solid mechanics and thermo...

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
no application Login to view more
IPC IPC(8): G06F17/50
CPCG06F30/23G06F30/367
Inventor 邱志平苏欢王磊王晓军孙佳丽
Owner BEIHANG UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap