This copper contains 99.9% Cu with 0.045 O content.
• Used for the production of wire, rod plate and strip.
• Oxygen is almost insoluble in copper and forms Cu2O
interdendritic eutectic upon solidification.
• Hot-working process breaks up this Cu2O network and appears
as particles aligned in the working direction.
• Exposed to H2 at T> 400oC leads to pressure build up at grain
boundaries, causing fracture. (hydrogen embrittlement)