For research purpose on material selection for nuclear applications an Inconel tube (Ni-Cr alloy) was tested on burst pressure of the tube wall. Therefore the tube had to be sealed hermetically. The tube wall thickness is 0.5mm.Because of the tight tollerances for sealing the tube and pressure testing it afterwards, only laser welding could be applied in this case. The laser welding tests were carried out using a 400W Nd-YAG laser in pulsed mode. The sealed tubes were ubsequently tested at 1400 bar.All laser welds could withstand this pressure.