BS 970 (Part 1):1983 080M50 Steel: Specifications & Listings

Residual elements: see clause 1.7.3.

Source: BS 970 (Part 1):1983, Table 6

Heat treatment to be given to test bars and to material required in the finally heat treated condition. Note 24: O = oil, W = water. Where oil hardening is specified, either a well-agitated conventional oil or a proven synthetic quenchant may be used. Synthetic quenchants shall not be used for the heat treatment of test bars for material not supplied in the finally heat treated condition.

Source: BS 970 (Part 1):1983, Table 7

Condition	Limiting ruling section (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
Q	150	625-775	390	15	-	-	360	179-229
R	63	700-850	430	14	-	-	400	201-255
S	29	775-925	495	14	-	-	465	223-277
T (note 13)	13	850-1000	570	12	-	-	555	248-302

Values as printed in Table 6 for the limiting ruling section shown. Rp0.2 applies when specifically ordered (note 10). 1 N/mm2 = 1 MPa. Note 13: may not always be obtained by bulk heat treatment, but the properties can be achieved by the appropriate heat treatment of die forgings and components, and also apply to test bars.

Source: BS 970 (Part 1):1983, Table 6

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	620 min	310	14	-	-	-	179-229 (note 4)
Normalized + turned or ground	-	over 150 to 250	570 min	295	14	-	-	-	163-217 (note 4)
Normalized + cold drawn or normalized + cold drawn + ground	-	6 to 13	740 min	590	7	-	-	555	-
Normalized + cold drawn or normalized + cold drawn + ground	-	over 13 to 16	730 min	585	8	-	-	545	-
Normalized + cold drawn or normalized + cold drawn + ground	-	over 16 to 40	690 min	555	8	-	-	485	-
Normalized + cold drawn or normalized + cold drawn + ground	-	over 40 to 63	680 min	540	9	-	-	420	-
Normalized + cold drawn or normalized + cold drawn + ground	-	over 63 to 76	650 min	510	10	-	-	400	-
Hardened and tempered + turned or ground	Q	6 to 150	625-775	390	15	-	-	360	179-229
Hardened and tempered + turned or ground	R	6 to 63	700-850	430	14	-	-	400	201-255
Hardened and tempered + turned or ground	S	6 to 29	775-925	495	14	-	-	465	223-277
Hardened and tempered + turned or ground	T (note 13)	6 to 13	850-1000	570	12	-	-	555	248-302
Hardened and tempered + cold drawn or hardened and tempered + cold drawn + ground	Q	13 to 150	625-775	430	11	-	-	390	179-229 (note 4)
Hardened and tempered + cold drawn or hardened and tempered + cold drawn + ground	R	6 to 63	700-850	490	10	-	-	450	201-255 (note 4)
Hardened and tempered + cold drawn or hardened and tempered + cold drawn + ground	S	6 to 29	775-925	540	10	-	-	500	223-277 (note 4)
Hardened and tempered + cold drawn or hardened and tempered + cold drawn + ground	T (note 13)	6 to 13	850-1000	595	9	-	-	550	248-302 (note 4)
Turned, ground or cold drawn and finally softened	-	-	-	-	-	-	-	-	187 max

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. Note 13: may not always be obtained by bulk heat treatment, but the properties can be achieved by the appropriate heat treatment of die forgings and components, and also apply to test bars.

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