FREE CUTTING STEELS

FREE CUTTING STEELS

Free cutting steels are steels with low machining manufacturing cost generally due to broken machining in fast chipping process. Due to their easy processability, such steels are the ones most suitable for machining processes such as longitudinal turning and facing in revolver or multishaft turning lathes, toothing, drilling and reaming.

			STEELS NOT UNDERGOING HEAT TREATMENT
			CHEMICAL COMPOSITION
Material No	Symbol	AISI-SAE	C	Si	Mn	Pmax	S	Pb
1.0711	9S20	1212	<0,13	<0,05	0,60 1,20	0,1	0,18 0,25
1.0715	9SMn28	1213	<0,14	<0,05	0,90 1,30	0,1	0,24 0,32
1.0718	9SMnPb28	12L13	<0,14	<0,05	0,90 1,30	0,1	0,24 0,32	0,15 0,30
1.0736	9SMn36	1215	<0,15	<0,05	1,00 1,50	0,1	0,32 0,40
1.0737	9SMnPb36	12L14	<0,15	<0,05	1,00 1,50	0,1	0,32 0,40	0,15 0,30
			STEELS SUBJECT TO CEMENTATION PROCESS
			CHEMICAL COMPOSITION
Material No	Symbol	AISI-SAE	C	Si	Mn	Pmax	S	Pb
1.0721	10S20	1108	0,07 0,13	0,10 0,40	0,50 0,90	0,06	0,15 0,25
1.072	10SPb20	11L08	0,07 0,13	0,10 0,40	0,50 0,90	0,06	0,15 0,25	0,15 0,30
			STEELS SUBJECT TO QUENCHING AND TEMPERING PROCESS
			CHEMICAL COMPOSITION
Material No	Symbol	AISI-SAE	C	Si	Mn	Pmax	S	Pb
1.0726	35S20	1140	0,32 0,39	0,10 0,40	0,50 0,90	0,06	0,15 0,25	-
1.0727	45S20	1146	0,42 0,50	0,10 0,40	0,50 0,90	0,06	0,15 0,25	-
1.0728	60S20	-	0,57 0,65	0,10 0,40	0,50 0,90	0,06	0,15 0,25	-

FIELDS OF USE
Material No	Symbol	AISI-SAE
1.0711	9S20	1212	Mass production parts in automobile industry, apparatus and device making
1.0715	9SMn28	1213	Mass production parts in automobile industry, device and apparatus making
1.0718	9SMnPb28	12L13	Mass production parts in automobile industry, device and apparatus making
1.0736	9SMn36	1215	Mass production parts in automobile industry, device and apparatus making
1.0737	9SMnPb36	12L14	Mass production parts in automobile industry, device and apparatus making
1.0721	10S20	1108	It is used in mass production in automobile industry, device and apparatus making
1.072	10SPb20	11L08	Mass production parts in automobile industry, device and apparatus making
1.0726	35S20	1140	High-strength mass production parts for automobile industry, device, apparatus and machines
1.0727	45S20	1146	Medium-strength mass production parts for automobile industry, device, apparatus and machines
1.0728	60S20	-	High-strength mass production parts for automobile industry, device, apparatus and machines

MECHANICAL PARTICULARITIES IN PROCUREMENT OF FREE CUTTING STEELS IN COLD ROLLED OR NORMAL TEMPERED FORM

			cold rolled													normal annealed
			Tensile strength Rm				Yielding point Re				Elongation A				normal	Tensile strength Rm			Yielding point Re			Elongation
			≤10 mm	>10 ≤16 mm	>16 ≤40 mm	>40 ≤63 mm	≤10 mm	>10 ≤16 mm	>16 ≤40 mm	>40 ≤63 mm	≤10 mm	>10 ≤16 mm	>16 ≤40 mm	>40 ≤63 mm	tavlama sıcaklığı	≤16 mm	>16 ≤40 mm	>40 ≤63 mm	≤16 mm	>16 ≤40 mm	>40 ≤63 mm	A
Material No	Symbol	AISI-SAE	Mpa				Mpa				Mpa				ᵒC	Mpa			Mpa			> %
1.0711	9S20	1212	540 780	490 740	460 710	390 640	410	390	355	295	7	8	9	10	890 920	≥350	≥350	≥350	225	215	205	25
1.0715	9SMn28	1213	560 800	510 760	460 710	410 660	440	410	375	305	6	7	8	9	890 920	≥370	≥370	≥370	235	225	215	23
1.0718	9SMnPb28	12L13	560 800	510 760	460 710	410 660	440	410	375	305	6	7	8	9	890 920	≥370	≥370	≥370	235	225	215	23
1.0736	9SMn36	1215	560 800	540 780	430 680	430 680	440	430	390	315	6	7	8	9	890 920	≥380	≥370	≥360	235	225	215	23
1.0737	9SMnPb36	12L14	560 800	540 780	430 680	430 680	440	430	390	315	6	7	8	9	890 920	≥380	≥370	≥360	235	225	215	23
1.0721	10S20	1108	540 780	490 740	460 710	390 640	410	390	355	295	7	8	9	10	890 920	≥350	≥350	≥350	225	215	205	25
1.072	10SPb20	11L08	540 780	490 740	460 710	390 640	410	390	355	295	7	8	9	10	890 920	≥350	≥350	≥350	225	215	205	25
1.0726	35S20	1140	640 880	590 830	540 740	510 710	490	400	315	285	6	7	8	9	860 890	480 600	480 600	480 600	295	285	275	18
1.0727	45S20	1146	740 980	690 930	640 840	610 800	570	470	375	325	5	6	7	8	840 870	580 700	580 700	580 700	335	325	315	14
1.0728	60S20	-	830 1080	780 1030	740 930	710 900	645	540	430	355	5	6	7	8	820 850	660 780	650 770	640 760	365	355	345	9

MECHANICAL PARTICULARITIES IN PROCUREMENT OF FREE CUTTING STEELS

			In material procurement (unprocessed or peeled)
			hardness				tensile strength
			<10 mm	11-16 mm	17-40 mm	41-63 mm	<10 mm	11-16 mm	17-40 mm	41-63 mm
Material No	Symbol	AISI-SAE	≤ BSD 30				Mpa
1.0711	9S20	1212	159	159	149	149	360 530	360 530	360 530	360 530
1.0715	9SMn28	1213	170	170	159	159	380 570	380 570	380 570	380 570
1.0718	9SMnPb28	12L13	170	170	159	159	380 570	380 570	380 570	380 570
1.0736	9SMn36	1215	174	174	163	159	390 590	390 590	380 550	370 540
1.0737	9SMnPb36	12L14	174	174	163	159	390 590	390 590	380 550	370 540
1.0721	10S20	1108	159	159	149	149	360 530	360 530	360 530	360 530
1.072	10SPb20	11L08	159	159	149	149	360 530	360 530	360 530	360 530
1.0726	35S20	1140	197	197	192	192	490 660	490 660	490 660	490 660
1.0727	45S20	1146	229	229	223	223	590 760	590 760	590 760	590 760
1.0728	60S20	-	269	269	261	261	670 880	670 880	660 870	650 860

HEAT TREATMENT CONDITIONS AND GAINED MECHANICAL PARTICULARITIES IN FREE CUTTING STEELS

			Heat Treatment Conditions									Mechanical Particularities
												Tensile strength (Rm)			Yielding point (Re)			Elongation (A)
			case hardening temperature	hardening temperature	Shock cooling			Case hardening			Tempering temperature	≤16mm	>16 ≤40 mm	>40 ≤63 mm	≤16mm	>16 ≤40 mm	>40 ≤63 mm	≤10 mm	>10 ≤16 mm	>16 ≤40 mm	>40 ≤63 mm
Material No	Symbol	AISI-SAE	ᵒC	ᵒC	water	oil	hot bath	water	oil	hot bath	ᵒC	Mpa			≥ Mpa			≥ %
1.0711	9S20	1212	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-
1.0715	9SMn28	1213	880 950	880 920	*	-	*	*	*	*	150 200	-	-	-	-	-	-	-	-	-	-
1.0718	9SMnPb28	12L13	880 950	880 920	*	-	*	*	*	*	150 200	-	-	-	-	-	-	-	-	-	-
1.0736	9SMn36	1215	880 950	880 920	*	-	*	*	*	*	150 200	-	-	-	-	-	-	-	-	-	-
1.0737	9SMnPb36	12L14	880 950	880 920	*	-	*	*	*	*	150 200	-	-	-	-	-	-	-	-	-	-
1.0721	10S20	1108	880 950	880 920	*	*	*	*	*	*	150 200	-	-	-	-	-	-	-	-	-	-
1.072	10SPb20	11L08	880 950	880 920	*	-	*	*	*	*	150 200	-	-	-	-	-	-	-	-	-	-
1.0726	35S20	1140	-	850 890	*	-	-	-	-	-	540 680	620 760	580 730	540 690	420	365	352	13	14	16	17
1.0727	45S20	1146	-	850 890	-	-	-	-	-	-	540 680	700 840	660 800	620 760	480	410	375	10	11	13	14
1.0728	60S20	-	-	800 840	-	-	*	-	-	-	540 680	830 980	780 930	740 880	570	490	450	7	8	10	11