Showing papers in "Engineering Fracture Mechanics in 1968"

TL;DR: In this article, the leading edge of a crack is treated as a line disturbance zone in a manner similar to the treatment of dislocation lines in dislocation mechanics, and the authors discuss interpretation of the brittle-ductile transition in terms of relative plastic zone size, and allowable load estimates which include fracture strength in a rational way.

TL;DR: The major evidence bearing upon sub-critical flaw growth in structural materials is reviewed and discussed in this paper, focusing on the growth of pre-existing flaws at operating stresses less than the net section yield strength, from both the separate and combined effects of fatigue and aggressive environments.

TL;DR: In this paper, the authors present results of acoustic emission studies on flawed and unflawed specimens of aluminum and beryllium and show that acoustic emission from the flawed specimens is found to begin at stress levels far below the general yield stress.

TL;DR: In this paper, a theoretical model for predicting elastic-plastic, plane strain stress distributions in notched bars under bend loading has been developed by combining the elastic solutions of Neuber with the slipline field solutions of Hill.

TL;DR: A comprehensive review of the development and the current state-of-the-art for the WOL (wedge opening loading) specimen for plane strain fracture toughness testing is described in this paper.

TL;DR: In this article, a theoretical basis for the maximum load-carrying capacity of sharply notched aluminum columns loaded eccentrically in compression was given, and a failure criterion was developed.

TL;DR: In this article, the interrelationships among fine-scale microstructure, strength, and toughness have been investigated, including embrittlement phenomena, the effects of residual or impurity elements, and the micromechanisms of crack propagation.

TL;DR: In this article, the effects of moisture and hydrogen on the rates of fatigue-crack propagation and on the fracture path through the microstructure of 18Ni(250) maraging steel were examined at room temperature in dry and humid argon and hydrogen environments.

TL;DR: In this paper, the general character of the linear elastic solution near the periphery of the crack is determined such that local stresses and displacements can be expressed independently of uncertainties of both the crack geometry and magnitude of the applied load.

TL;DR: In this paper, the authors extended the Dugdale model to include the influence of the stress-strain curve on the plastic-zone size and subsequently on the fracture strength of the plate.

TL;DR: In this paper, a brief and cursory discussion attempts to point out the more important microstructural factors, which may be expected to affect the toughness of high strength alloys, in which fracture occurs by void nucleation and coalescence.

TL;DR: In this article, the effects of thickness and testing direction upon the plane strain and plane stress fracture toughness of 7075-T6 and -T651 aluminum alloy were examined, both by static center-notched tests and precracked Charpy impact tests.

TL;DR: In this article, the authors used a piezoelectric crystal to convert the elastic stress wave into an electrical signal, which can be used to detect the onset of crack growth.

TL;DR: In this article, the authors investigated the subcritical crack growth behavior during the fracture toughness testing of several structural alloys and compared with the crack propagation characteristics observed under fatigue loading conditions.

TL;DR: In this paper, the size of the plastic enclave at the tip of a crack within an externally loaded elastic medium is estimated for the complete understanding of the stress distribution in the cracked medium.

TL;DR: In this paper, the authors studied the distribution of stresses near an embedded flat parabolic crack in a body of infinite extent when the crack surface is subjected to uniform normal loading and showed that the crack opening shape is an elliptic paraboloid.

TL;DR: In this paper, the diffraction of a plane flexural wave by a through-the-thickness crack in an elastic plate is examined by application of Mindlin's theory of flexural motions of plates.

TL;DR: In this article, the effect of specimen type on the room temperature plane strain fracture toughness of three aluminum alloys: 7079-T6, 7075-T 6, and 7001-T75, is presented.

TL;DR: The results of exploratory stress corrosion tests conducted in simulated sea water at an ambient pressure of 10,000 psi and at atmospheric pressure are described in this paper, and it appears that increasing the ambient pressure on the test specimen may decrease its stress corrosion susceptibility.

TL;DR: The fracture toughness of a 1−1 case 3 8 in. plate of ten combinations of alloy and temper has been determined with center-notch tension (CN), single-edge-notched tension (SEN), and notch-bend (NB) tests as mentioned in this paper.

TL;DR: In this article, an integral formulation for a plate subjected to periodic transverse vibrations of frequency ω and containing a crack of length 2c, is solved for the Kirchhoff bending stresses.

TL;DR: In this article, a relationship between drop-weight tear test energy and explosion tear test performance was established for high-strength titanium alloys, and the relationship appeared to be valid up to a DWTT value of 1200ft-lb.

TL;DR: In this article, the energy balance theory for the fracture propagation in brittle and quasi-brittle materials is discussed in a toroidal region around the crack periphery, and the results are applied to the fracture of an infinite medium containing a central through crack and subjected to antiplane shear loads at infinity.