Product Code: PIC06_1007

Cleaning Oxides from Copper Artifacts using a Frequency-doubled Nd:YAG Laser
Authors:
Alexander Kaplan, Luleå University of Technology; Lulea Sweden
Yang Sook Koh, Kiruna Center for Conservation of Property; Kiruna Sweden
John Powell, Laser Expertise Ltd.; Nottingham Great Britain
Göran berg, Luleå University of Technology; Luleå Sweden
Johnny Grahn, Luleå University of Technology; Luleå Sweden
Presented at PICALO 2006

This paper presents the results of an experimental program investigating the ablation of oxides from copper alloy surfaces using a frequency doubled Nd:YAG Laser. One eventual use for this technique would be in the feild of ancient artifact conservation. A collection of old coins with similar levels of surface oxidation were cleaned using a range of laser pulsing parameters. It was discovered that a very uniform cleaned surface can be produced using a two stage process where the direction of the second laser raster pattern is at 90 degrees to the first. An operating regime has been identified within which the surfaces can be cleaned without thermal damage to the substrate.