Using cold working fastener holes is a simple life enhancement procedure that strengthens metallic components by retarding crack growth around a hole. In the present paper, the residual stress field that is induced by the hole expansion process is obtained based on different material models namely elastic perfect plastic, isotropic hardening and kinematic hardening using three-dimensional finit...

Ni 3Al, an L12 structure intermetallic crystal, is the basic composition of the y' precipitates in nickel-based superalloys and is a major strengthening mechanism contributing to the superalloys' outstanding high-temperature mechanical properties. Many L12-structure crystals present unusual macroscopic mechanical properties, including the anomalous temperature-dependence of yield strength and s...

Seedlings of Leptospermum scoparium J.R. et G. Forst (manuka) originating from seed from a low altitude coastal site (Auckland) and from a high altitude inland site (Desert Road) were grown for 96 days in four controlled environments to compare the relationship between growth temperature and frost hardening. Day/night temperature treatments were 12/6, 12/3, 12/0 and 12/-3 degrees C. Frost hardi...

Security plays a predominant role in software engineering. Enforcing security policies should be considered during the early stages of the software development lifecycle to prevent security breaches in the final products. Because of the pervasive nature of security, integrating security solutions at the software design level may result in the scattering and tangling of security concerns through...

In computed tomography (CT), reconstructions from conebeam (CB) data acquired with a polychromatic X-ray device show so called beam hardening artifacts. Beam hardening artifacts are highly undesirable for a medical diagnosis, because details in the reconstructed image are severely disturbed or completely lost. In this work, we demonstrate the significant reduction of beam hardening artifacts by...

This paper presents a mathematical characterization and analysis of beam-hardening artefacts in X-ray computed tomography (CT). In the field of dental and medical radiography, metal artefact reduction in CT is becoming increasingly important as artificial prostheses and metallic implants become more widespread in ageing populations. Metal artefacts are mainly caused by the beam-hardening of pol...

Local strength of friction stir (FS) welds and FS processed aluminium alloys in heat treatable aluminium alloys is dominated by precipitation hardening. Strengthening due to stored dislocations is generally limited to 40MPa, and grain size strengthening is generally less than 10MPa. Local crystallographic texture can cause yield strength variation on the order of 5%. Published models for streng...

The administrators of a mission critical network usually have to worry about non-traditional threats, e.g., how to live with known, but unpatchable vul­ nerabilities, and how to improve the network’s resilience against potentially un­ known vulnerabilities. To this end, network hardening is a well known preven­ tive security solution that aims to improve network security by taking proactive act...

This study deals with the relation between the microstructure of semi-crystalline polymers and their intrinsic deformation and fracture behaviour. For this purpose, the deformation and failure of well-characterised PET, PE and PP samples have been investigated thoroughly. Compression tests on amorphous and cold crystallised PET showed that the strain hardening remained unchanged, despite the de...

While the expenses for computational power decrease, iterative reconstruction methods for x-ray computed tomography (CT) that allow the use of improved model assumptions, become more attractive. In applications for non-destructive testing one of the most common degradations of image quality with standard x-ray CT reconstruction methods is beam hardening. Techniques for beam hardening correction...