BS 10263-1:2017 pdf download – Steel rod, bars and wire for cold heading and cold extrusion Part 1: General technical delivery conditions
7.7Hardenability requirements
7.7.1 General
Products cannot be ordered and supplied according to both end quench test hardenability requirementsand core hardening requirements
7.7.2 End quench (Jominy test) hardenability requirements
In cases where a product is ordered with reference to a steel grade the designation of which is quotedin Tables 8 and 9 of EN 10263-3:2017 or in Tables 9 to 11 of EN 10263-4:2017, the product shall meet thehardenability requirements indicated in those tables.For the verification, see 10.2.1.
7.7.3 Core hardening requirements
ln cases where a product is ordered with reference to a steel grade the designation of which is quotedin Table 12 of EN 10263-4:2017, core hardening properties shall meet the requirements indicated in therelevant tables.
At least 90 % of the structure shall be martensite.
In cases of dispute regarding supplies of products with diameters larger than those quoted in Table 12of EN 10263-4:2017, samples to be tested shall be brought to the corresponding dimensions indicated inthat table by hot working or forging, taking into account the requirements of EN ISO 642.
7.7.4 Hardenability by calculation
See 10.2.
7.8Microstructure
7.8.1 Austenitic grain size
Steels of EN 10263-3:2017 and of EN 10263-4:2017 shall show a fine grain structure with an austeniticgrain size of 5 or finer, when tested in accordance with EN ISO 643.For verification, see A.3.
Concerning steels of EN 10263-2:2017 and EN 10263-5:2017, unless otherwise specified at the time ofenquiry and order, the choice of the austenitic grain size is left to the manufacturer’s discretion.
7.8.2Carbide spheroidization
For steels covered by Parts 2, 3 and 4 of this European Standard, in cases where carbide spheroidizationis requested reference shall be made to A.4.
7.8.3 Non-metallic inclusions
The steels of EN 10263-3:2017 and EN 10263-4:2017 shall have a certain degree of cleanness, howeververification of the non-metallic inclusion content requires a special agreement at the time of enquiryand order (see A.5).
7.9Internal soundness
7.9.1 Rod, bars and wire shall be free from internal defects which may cause an adverse effect on theproduct during cold heading or cold extrusion or during heat treatment.
7.9.2 Requirements concerning internal soundness can be agreed at the time of enquiry and order, e.g.with reference to non-destructive tests (see A.6).
7.10 Surface quality
7.10.1 General
The surface quality requirements for steels of Parts 2, 3 and 4 of this European Standard are as follows.Those for steels of Part 5 are given in that Part.
7.10.2 Hot rolled products
7.10.2.1 Rod shall meet surface quality requirements according to EN 10221:1995,class D.For certainapplications surface quality E according EN 10221:1995 is appropriate and may be agreed at time ofenquiry and order (see Option 16).
7.10.2.2 Bars shall meet surface quality requirements according to EN 10221:1995 class D. Compliancewith surface quality according to EN 10221:1995 class E may be agreed at the time of enquiry and order.When the diameter of the product is greater than the maximum diameter specified in EN 10221, for thesurface quality class concerned, the maximum permissible depth of surface defects on the product shallnot be greater than that specified for this maximum diameter.
7.10.3 Bright products
For wire the permissible depth of surface discontinuities shall be in proportion to the reduction of thediameter during cold drawing. Depending on the starting material for cold drawn products the samerequirements apply as specified in 7.10.2.1 respectively.
Bright bars shall comply with the surface quality class 3 ofEN 10277-1:2008,Table 1.7.10.4 Removal of surface defects and imperfections
Removal of surface defects and imperfections is permitted only after approval from the purchaser.7.11 Decarburisation
Independently of their heat treatment condition, rod and bars with as-rolled surface of steels specifiedin Table 3 of EN 10263-3:2017 and in Tables 3 and 4 of EN 10263-4:2017 and wire shall be free fromzones of total decarburisation.
For bars annealed in an atmosphere which is not controlled the depth of decarburisation shall be agreedat the time of enquiry and order.
Partial decarburisation (ferrite-pearlite) is admissible provided that it does not exceed the limitsindicated in Figure 1. For diameters s i0 mm the maximum admissible depth of decarburisation isE=0,07 mm; for diameters greater than 10 mm the diagram corresponds to the formula E=0,007x d.