Chemical Compositions of Nuts

according to ISO 898, part 2

Property class		Chemical composition in terms of % by weight (test analysis)
Class		C (max.)	Mn (min.)	P (max.)	S (max.)
41), 51), 61)	–	0.50	–	0.060	0.150
8, 9	041)	0.58	0.25	0.060	0.150
102)	052)	0.58	0.30	0.048	0.058
122)	–	0.58	0.45	0.048	0.058

1) Nuts of these strength classes may be made from free cutting steel, unless other arrangements have been agreed upon between the buyer and the supplier. When using free cutting steel, the following maximum proportions of sulphur, phosphorus and lead are permitted: sulfur 0.34%, phosphorus 0.11%, lead 0.35%.

2) For these strength classes it may be necessary to add alloys in order to achieve the mechanical properties of the nuts.