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The purpose of this paper was to investigate an influence of a low temperature pressureless sintering process of silver paste on the quality of sintered joints.

The authors analyzed various curing conditions of the paste during its sintering process: 175°C/90 min, 200°C/60 min, 250°C/30 min, 250°C/60 min, 350°C/30 min and 350°C/60 min. They analyzed an influence of the surface plating applied on a ceramic substrate/layer (Cu, Ag, AgPt and Au thick film) on the joints quality. The authors analyzed microstructure and electrical resistance of the joints. They evaluated these properties from the point of view of thermal aging process and changing resistance, after a constant current loading of the sintered joints.

The nanoscale pressureless silver paste can be applied for replacing a pressure-assisted micro-sized silver paste. It was found that the quality of the metal plating applied on the ceramic substrate/layer has a significant impact on the quality of the sintered joints. Copper and AgPt plating have better impact on quality of sintered joints in compare with Ag plating.

This investigation of the quality of the pressureless sintered joints at the silver-silver interface reveals an evident cracking immediately after the silver paste curing. Rapid sintering process typical for silver-based films on the substrate is because of the inter-diffusion between the micro and nanoparticles of silver at interfacial interface.

The purpose of this paper is to examine the extent of accidents amongst child workers and to test the hypothesis that the tendency to have an accident is related to low perception of risk.

Over 700 Year 10 school students answered questionnaires concerning their experience of employment. The school students completed another questionnaire in year 11; from these 55 working children were selected to be interviewed and respond to a new tool, the Job Risk Card Sort.

Whereas 45 per cent of the interviewees had reported having had an accident in the questionnaire, this rose to 80 per cent in the interview. Those who stated in the questionnaire that they had had an accident tended to have lower perception of risk on the card sort than those who did not, thus supporting the hypothesis.

Previous questionnaire‐based research on accidents amongst young workers may have underestimated their extent. Further investigation of risk perception and accidents should be undertaken with a larger sample and more sophisticated techniques.

Procedures to safeguard young workers against accidents should be strengthened.

This is the most detailed study of accidents to child employees so far undertaken in Britain.