A robust approach for the determination of Gurson model parameters
Journal Title: Frattura ed Integrità Strutturale - Year 2016, Vol 10, Issue 37
Abstract
Among the most promising models introduced in recent years, with which it is possible to obtain very useful results for a better understanding of the physical phenomena involved in the macroscopic mechanism of crack propagation, the one proposed by Gurson and Tvergaard links the propagation of a crack to the nucleation, growth and coalescence of micro-voids, which is likely to connect the micromechanical characteristics of the component under examination to crack initiation and propagation up to a macroscopic scale. It must be pointed out that, even if the statistical character of some of the many physical parameters involved in the said model has been put in evidence, no serious attempt has been made insofar to link the corresponding statistic to the experimental and macroscopic results, as for example crack initiation time, material toughness, residual strength of the cracked component (R-Curve), and so on. In this work, such an analysis was carried out in a twofold way: the former concerned the study of the influence exerted by each of the physical parameters on the material toughness, and the latter concerned the use of the Stochastic Design Improvement (SDI) technique to perform a “robust” numerical calibration of the model evaluating the nominal values of the physical and correction parameters, which fit a particular experimental result even in the presence of their “natural” variability.
Authors and Affiliations
R. Sepe, G. Lamanna, F. Caputo
Keywords
Related Articles
- EP ID EP90799
- DOI 10.3221/IGF-ESIS.37.48
- Views 72
- Downloads 0
Previsione della resistenza a fatica in saldature per punti attraverso modellazione solida
Nel presente lavoro vengono messi a confronto due metodi idonei per la verifica di giunzioni saldate per punti: il metodo del raggio di raccordo fittizio ed il metodo del gradiente implicito. Il primo impone un raggio di...
Kinetics of fatigue crack growth and crack paths in the old puddled steel after 100-years operating time
The goal of the authors’ investigations was determination of the fatigue crack growth in fragments of steel structures (of the puddled steel) and its cyclic behavior. Tested steel elements coming from the turn of&...
Influence of the crack propagation rate in the obtaining opening and closing stress intensity factor by finite element method
Crack propagation simulation began with the development of the finite element method; the analyses were conducted to obtain a basic understanding of the crack growth. Today structural and materials engineers...
Wedge splitting test method: quantification of influence of glued marble plates by two-parameter fracture mechanics
In the present paper, the well-known wedge splitting test (WST) is applied on specimens with different geometries (S= 150, 200, 300 mm) and variants of the specimens’ configurations. K-calibration (B1) and T-stre...
Very high cycle fatigue strength and crack growth of thin steel sheets
For basic observations or for industrial applications it is of interest to use flat specimens at very high frequency in the gigacycle regime. In this work, thin flat sheet, with 1.2 mm thickness of a complex phase...