BS 970 (Part 1):1983 070M20 Steel: Specifications & Listings

Residual elements: see clause 1.7.3.

Source: BS 970 (Part 1):1983, Table 4 (bright bar)

Condition	Heat treatment condition	Size, diameter or across flats (mm)	Rm (N/mm2)	Re min (N/mm2)	A min (%)	Izod min (ft lbf)	KCV min (J)	Rp0.2 min (N/mm2), when specifically ordered	HB
Normalized + turned or ground	-	6 to 150	430 min	215	21	-	-	-	126-179 (note 4)
Normalized + turned or ground	-	over 150 to 250	400 min	200	21	-	-	-	116-170 (note 4)
Hot rolled + cold drawn or hot rolled + cold drawn + ground	-	6 to 13	560 min	440	10	-	-	420	-
Hot rolled + cold drawn or hot rolled + cold drawn + ground	-	over 13 to 16	530 min	420	12	-	-	390	-
Hot rolled + cold drawn or hot rolled + cold drawn + ground	-	over 16 to 40	490 min	370	12	-	-	340	-
Hot rolled + cold drawn or hot rolled + cold drawn + ground	-	over 40 to 63	480 min	355	13	-	-	290	-
Hot rolled + cold drawn or hot rolled + cold drawn + ground	-	over 63 to 76	450 min	325	14	-	-	280	-

Size is the diameter or across flats. For cold drawn bar of 6 mm or less, all mechanical properties are subject to agreement between purchaser and supplier at the time of enquiry and order (note 8). For normalizing and hardening and tempering treatments see Tables 3 and 7 (note 9). Rp0.2 applies when specifically ordered (note 10). 1 N/mm2 = 1 MPa. Hardness values marked note 4 are for guidance only.

Source: BS 970 (Part 1):1983, Table 4 (bright bar)

Appendix D note 47: where a comparison is made the steels are not necessarily equivalent. 'Not listed' means the earlier edition has no entry under this designation.

Source: BS 970 (Part 1):1983, Appendix D