Crack Paths 2006

observable [8]. Because this is not taken into account within a 2D finite element

simulation the distributions are different.

Figure 7.

Theoretical distribution:

Experiments:

Comparison of theoretical

crack growth rates in the

adjacencies of the notch

with experimental data [8]

C O N C L U S I O N S

For the determination of threshold values different standards, e.g. A S T ME 647, are

available. Within the scope of this paper different parameters of the threshold

determinations have been investigated. It can be concluded that the initial value Kmax,0

as well as the slope has no influence on the threshold values of the quenched and

tempered steel, but there exists an effect on the investigated aluminium alloy. Moreover

by means of SN-curve of cracked and notched specimen initiation cycles have been

determined.

R E F E R E N C E S

1.

A S T M(1997). Annual Book of ASTMStandards 1997. Section 3: Metals Test

Methods and Analytical Procedures, Volume 03.01, Metals – Mechanical Testing;

Elevated and Low-Temperature Tests; Metallography, ASTM,West Conshohocken

2. Döker, H. (1997). Intern JFatigue 19, S145-S149

Tabernig, B.; Pippan, R. (2002). Engineering Fracture Mechanics 69, 899-907

3.

4. Tabernig, B.; Powell, P.; Pippan, R. (2000). In: Fatigue crack growth thresholds,

Endurance limits, and design, A S T MSTP 1372, pp. 96-108, Newman, J. R. Jr.;

Piascik, R. S. (Eds.), ASTM,West Conshohocken

5. Newman,J. C. Jr. (2000). In: Fatigue crack growth thresholds, Endurance limits,

and design, A S T M S T 1P372, pp. 227-251, Newman,J. R. Jr.; Piascik, R. S. (Eds.),

ASTM,West Conshohocken

6.

Forth, S. C.; Newman,J. C. Jr.; Forman, R. G. (2003). Intern JFatigue 25, 9-15

7.

Sander, M.; Richard, H. A. (2006). F F E M S29, 291

8. Wingenbach, M. (1994) PhD-thesis, University of Paderborn, Germany