33B2 冷镦钢丝

Elements not quoted in this table should not be intentionally added to the steel without the agreement of the purchaser,except those intended for finishing the heat.All reasonable precautions shall be taken in order to prevent the addition of such elements from scrap or other materials used in the production process,which can affect the hardenability, mechanical properties and applicability To improve the performance of cold heading,it is possible to add Al:0,020 %to 0,050 %.Maximum values unless otherwise indicated. In the case of steels with hardenability requirements (see Table C.8),minor deviations from the specified limits are permitted (with the exception of sulfur and phosphorus)   c   Lower silicon contents may be agreed at the time of ordering,in which case due consideration should be given to the effects that could result for what concerns the specified properties such as,for example,hardenability. d Where a maximum chromium content of 0,30 %is specified,a minimum level may also be agreed at the time of enquiry and order e  In order to obtain a core hardening for the steel grade 30MoB1,the lower limit of Cr shall be 0,15 %and may be agreed at the time of enquiry and order.For certain applications, the higher limit for Cr may also be lowered by agreement at time of enquiry and order.