DETERMINATION OF COPPER IN A533B STEEL FOR THE ASSESSMENT OF RADIATION EMBRITTLEMENT USING LASER-INDUCED BREAKDOWN SPECTROSCOPY

Determination of radiation embrittlement in nuclear reactor pressure v essels is crucial to assessing safe operative lifetimes for many aging nuclear power plants. Conservative nuclear fluence estimates and trac e impurity diagnosis of the weldment material are the basis of radiati on embrittlement analysis. Copper is thought to be a key impurity cont ributing to radiation embrittlement. In this paper, the application of laser-induced breakdown spectroscopy (LIES) as a means to assess radi ation embrittlement by the detection and quantification of copper in A 553b steel was investigated. A LIBS configuration completely coupled b y fiber optics was attempted, but because of low laser power and fiber losses, fiber-optic delivery of the laser beam was unsuccessful. Cons equently, hard optics (lenses and mirrors) were employed for laser bea m delivery. The plasma emission was delivered successfully via fiber o ptics to the detection apparatus. Copper measurements were made from c ustom-fabricated steel samples, Comparison of the LIES results to an i ndependent atomic absorption spectrophotometry (AAS) analysis showed L IES to be of comparable accuracy, especially in low-level copper sampl es.