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The effect of surface condition on acoustic emission during welding of aluminium with CO2 laser radiation

W W Duley and Y L Mao

Journal of Physics D: Applied Physics, Volume 27, Number 7

A good rule of thumb with any welding operation is that the metal surface should be as clean as possible. Parent material cleanliness is critical especially in the case of laser or electron beam welding, particularly with regard to oils, paints, and surface treatments such as anodising in aluminium. Even an oxide layer, especially refractory oxides such that found on aluminium can have a detrimental effect on the microstructure  and thus structural integrity  of a completed weld.