2.5mm thick copper sheet C106 soft, 300mm x 300mm 0.092 13 gauge.
C106 (phosphorous deoxidised copper) is a grade of copper from which oxygen is removed by the controlled addition of phosphorus during the melting cycle. It is the material normally used for the manufacture of copper tubes as it can be readily welded or brazed. C106 has deep drawing characteristics superior even to those of tough pitch copper (C101).
The presence of phosphorous acts as a deoxidant, removing copper oxide which would otherwise react with hydrogen. The residual phosphorus remains alloyed with the copper within the specified range 0.013-0.050%. The copper content is 99.85% minimum and the grade should be specified for all non-electrical applications, especially those involving assembly by welding or brazing. Phosphorus deoxidised copper is not susceptible to hydrogen embrittlement which is a serious risk with non-deoxidised grades.