Cu has excellent electrical and thermal properties, therefore, it is amongst the most important materials for conducting electric power and for building up electrical systems. Typical industrial applications of interest are electrical contacts in automotive battery applications, microwave resonators, power generation.
As part of the Europen collaborative funded project QCOALA,Quality Control of Aluminium and copper Laser-welded Assemblies, a study was carried out on processing of thin copper C101 (Cu C101) and aluminium 3003 (Al 3003), using both infrared (IR), at 1064nm wavelength, and green, at 532nm wavelength, pulsed laser beam sources. The power density (peak power divided by the area of the minimum focused laser beam width) thresholds for keyhole initiation, when processing with the 1064nm laser source, were investigated for 1mm thickness Cu C101 and Al 3003 coupons respectively. Conduction limited melting and welding was carried out in the case of the green wavelength, due to the limited output power of the 532nm pulsed laser sources available. The increased absorptivity of Cu C101 at 532nm introduced improved stability in the process, compared to the results achieved with the 1064nm wavelength laser beam. However, the same behaviour was not observed in the case of Al 3003.
The full version of this article can be sourced on the QCOALA website.