Corrosion Fatigue Behaviour of Laser-welded Shape Memory NiTi Wires in a Simulated Body Fluid

Corrosion fatigue is a fracture process as a consequence of synergistic interactions between the material structure, corrosive environment and cyclic loads/strains. It is difficult to be detected and can cause unexpected failure of engineering components in use. This study reveals a comparison of corrosion fatigue behaviour of laser-welded and bare NiTi wires using bending rotation fatigue (BRF) test coupled with a specifically-designed corrosion cell. The testing medium was Hanks’ solution (simulated body fluid) at 37.5 oC. Electrochemical impedance spectroscopic (EIS) measurement was carried out to monitor the change of corrosion resistance of sample during the BRF test at different periods of time. Experiments indicate that the laser-welded NiTi wire would be more susceptible to the corrosion fatigue attack than the bare NiTi wire. This study can serve as a benchmark for the product designers and engineers to understand the corrosion fatigue behaviour of the NiTi laser weld joint and determine the fatigue life safety factor for NiTi medical devices/implants involving laser welding in the fabrication process.

Implications of divergences in Adult Protection legislation

Purpose – The purpose of this paper is to explore the similarities and differences of legal responses to older adults who may be at risk of harm or abuse in the UK, Ireland, Australia and the USA.
Design/methodology/approach – The authors draw upon a review of elder abuse and adult protection undertaken on behalf of the commissioner for older people in Northern Ireland. This paper focusses on the desk top mapping of the different legal approaches and draws upon wider literature to frame the discussion of the relative strengths and weaknesses of the different legal responses.
Findings – Arguments exist both for and against each legal approach. Differences in defining the scope and powers of adult protection legislation in the UK and internationally are highlighted.
Research limitations/implications – This review was undertaken in late 2013; while the authors have updated the mapping to take account of subsequent changes, some statutory guidance is not yet available. While the expertise of a group of experienced professionals in the field of adult safeguarding was utilized,
it was not feasible to employ a formal survey or consensus model.
Practical implications – Some countries have already introduced APL and others are considering doing so. The potential advantages and challenges of introducing APL are highlighted.
Social implications – The introduction of legislation may give professionals increased powers to prevent and reduce abuse of adults, but this would also change the dynamic of relationships within families and between families and professionals.
Originality/value – This paper provides an accessible discussion of APL across the UK and internationally
which to date has been lacking from the literature.