B19

Mass fraction wt%; Under 2.2, elements with specified lower and upper limits are alloying constituents; a single value is a minimum for copper and a maximum for other elements. A dash means unspecified; it is not entered as zero; Cu+Ag and Ni+Co are subject to combined ranges and are not converted into independent element ranges. The balance remains a balance; subtracting independent maxima does not establish a guaranteed range. Total impurities include all relevant impurities; The sum of listed elements is only a necessary condition and cannot replace complete impurity analysis. Product forms in the original document define the applicable wrought-product scope; they do not establish confirmed supply of cold-heading wire or final properties. Cu is the balance. Note 2: S≤0.05% material may be supplied for special-purpose B19 strip, subject to separate confirmation; the ordinary tabulated maximum 0.01% is not automatically widened. Note 1: Bi/As/Sb need not be analyzed; the supplier guarantees that the limit is not exceeded.

Mass fraction wt%; GB/T5231—2012, Table 5, row 3, designation T71050. Cu is the balance; Ni+Co is a coupled combined range and must not be applied independently to each element. Total impurities under Clause 2.3 are ≤1.8% and include all relevant impurities; a partial sum of listed elements cannot replace complete analysis. Table 5, note a: As/Bi/Sb need not be analyzed, but the supplier must still guarantee that the limit is not exceeded; Unlisted numerical values are not guessed or filled in. This standard covers wrought copper-nickel composition and does not establish actual supply of cold-heading wire. Table 5, note b: only special-purpose B19 copper-nickel strip permits S≤0.05%; ordinary conditions must not be widened automatically.