The main mechanical property headlines for CAL wrought CNC is the high strength and ductility combined with extremely high impact strength and shock resistance. Izod impact strength is around 3 times or 100J (74 ft lbf) higher than forged NAB to Def Stan 02-833 and around double that reported for cast CuNiCr. This important feature can be guaranteed (see table 2), measured and reported for each batch of material.
Available in two property conditions:
- CAL CNC-1: The standard material applicable to all product forms and sizes
- CAL CNC-2: High strength version applicable to bars (round/flat/square/hexagonal) up to around 150mm (6″) in section.
All mechanical test specimens used for acceptance testing are integral to the forgings or bars they represent and as such, the obtained results are entirely representative of the material. The figures in table 2 can therefore be used for design.
It is worth pointing out the cast version of this alloy (Def Stan 02-886) calls for small test bars that are separate to the castings they represent, and actual properties in the castings would routinely be lower. Because of this, Def Stan 02-886 suggests, for design purposes, a 0.2% proof stress of 240MPa (35Ksi) should be used, which is significantly lower than wrought CAL CNC-1 and 40% that of CAL CNC-2.
Tensile Test Standard: BS EN 2002-1
Impact Test Standard: BS 131 Part 1
Hardness Test Standard: BS EN ISO 6506-1