Cleaning method, laser-based

A particularly insidious failure mechanism that is commonly found in carbon-steel tubing is under-deposit corrosion. In many cases, corrosion products fomi a scab that can mask the presence of the pitting, making it difficult to quantitatively assess using conventional NDT methods. However, by combining proper cleaning procedures with laser-based inspection methods, the internal surface of the tubing can be accurately characterized and the presence of under-deposit corrosion can be confirmed and quantified. 

This goal is most clearly approached by methods based on vaporization of a metal by laser pulses, leading to a cloud of clean clusters of bare metal containing as few as one atom. Catalytic activity of clusters as a function of number of atoms can be obtained by time-of-flight mass spectrometry (16-18). 

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