Stainless Steel Data

Designation System for Stainless Steel (ISO 3506 1979)

Composition Groups	Austenitic			Ferritic		Martensitic
Identification of Steel Grades	A1, A2, A4			F1		C1, C4		C3
Property Class	50	70	80	45	60	50	70	80
Property Class	Soft	Cold- Worked	High- Strength	Soft	Cold-Worked	Soft	Hardened and Tempered	Hardened and Tempered

Extract from DIN 267 Part 11 - Chemical Composition of austenitic chromium-nickels steels in % by weight

Austenitic Grade	Material No. to AISI	C	Si	Mn	P	S	Cr	Mo	Ni
A1	303	0.12	1.0	2.0	0.20	0.15 to 0.35	17.0 to 19.0	0.6	8.0 to 10.0
A2	304	0.08	1.0	2.0	0.05	0.03	17.0 to 20.0	-	8.0 to 13.0
A4	316	0.08	1.0	2.0	0.05	0.03	16.0 to 18.5	2.0 to 3.0	10.0 to 14.4

Maximum values unless otherwise stated.
Types A2 and A4 may contain up to a maximum of 4% copper.
The selection of steel grades within a group is the prerogative of the manufacturer, unless the purchaser has specified particular steels to ISO or national standards.
Different grades of steel may be used as long as all physical and mechanical properties and the corresponding corrosion resistance of the finished product are achieved. Only when all these conditions are fulfilled may finished articles be marked in accordance with DIN 267 Part 11.

Bolts, Screws and Studs

Grade	Property Class	Tensile Strength Rm MPa (N/mm²) minimum	Yield Stress R_p 0.2 Mpa (N/mm²) minimum	Elongation A_L Minimum	Proof Load Stress Sp Mpa (N/mm²) minimum	Diameter Range
A2 and A4	70	700	450	0.4d	700	=<M20
A2 and A4	80	800	600	0.3d	800	=<M20

Tensile Load

A2 and A4 as compared to 304 and 316	Percent difference from US - Stainless Steel
up to M20	44% higher
M22 and over	6% lower

Guideline values for screws in steel groups A2-70 and A4-70 with standard metric threads to DIN 13

Diameter	Load ¹⁾ Force at 0.2% yield point N	Initial Stressing Force N	Tightening Torque Nm	Force in service N
Diameter	Load ¹⁾ Force at 0.2% yield point N	Initial Stressing Force N	Tightening Torque Nm	Axial Static	Axial Dynamic	Radial Static or Dynamic
M3	2250	1420	0.9	610	360	120
M4	3960	2490	2.2	1070	640	210
M5	6390	4030	4.3	1730	1040	350
M6	9040	5700	7.3	2440	1470	490
M8	16470	10380	17.7	4450	2670	890
M10	26100	16440	35.5	7050	4230	1410
M12	37930	23900	61.3	10240	6150	2050
M16	70650	44510	147.1	19080	11450	3820
M20	110250	69460	285.1	29770	17860	5950

1)The values correspond to 100% of the 0.2%

Notes on application:

When selecting the correct screw diameter it should be ensured that the total load on the screw does not exceed 90% of the standardized 0.2% yield stress. Care should be taken to ensure correct initial tensioning, with a torque wrench wherever possible.
Experience has shown that a utilization of 70% of the total load is reasonable average for the initial stressing force to allow additional forces in service to be taken up.

**The table above is only intended as an aid for quick comparison**

British	French	German	Italian	Japanese	Swedish	USA
304S21	Z12CN17.08	1.4310	X12CrNi 17 07	SUS301	14 23 31	301
304S31				SUS302	14 23 32	302
304S15 304S16	Z8CN18.09	1.4301	X5CrNi 18 10	SUS301	14 23 33	304
304S11	Z2CN18.10	1.4306	X2CrNi 18 11	SUS304L	14 23 52	304L
305S19	Z8CN18.12		X8CrNi 18 12	SUS305		305
309S24	Z15CN24.13		X16CrNi 23 14	SUS309		309
310S24	Z12CN25.20	1.4845	Z22CrNi 25 20	SUS310S	14 23 61	310
315S16					14 23 40
316S31 316S33	Z6CND17.11	1.4401 1.4436	X8CrNiMo 17 13	SUS316	14 23 43 14 23 47	316
316S11 316S13	Z2CND17.12	1.4404 1.4435	X2CrNiMo 17 12	SUS316L	14 23 53 14 23 48	316L
317S12	Z2CND19.15	1.4435	X2CrNiMo 18 16	SUS317L	14 23 67	317L
317S16		1.4436		SUS317	14 23 66	317
320S31 320S33	Z8CND17.12	1.4571 1.4573			14 23 50
321S31	Z6CNT18.12	1.4541	X6CrNiTi 18 11	SUS321	14 23 37	321
347S31	Z6CNNb18.11	1.4558	X6CrNiNb 18 11 X8CrNiNb 18 11	SUS347	14 23 38	347
403S17	Z6C13	1.4000	X6Cr13	SUS403	14 23 01	403
405S17	Z6CA13	1.4002	Z6CrA1 13	SUS405		405
409S19		1.4512				409
430S17	Z8C17	1.4016	X8Cr 17	SUS430	14 23 20	430
434S17	Z8CD17.01	1.4113	X8CrMo 17	SUS434	14 23 25	434
410S21	Z12C13	1.4006 1.4024	X12Cr 13	SUS410	13 23 02	410
410S45	Z30C13		X30Cr 13	SUS420JS	14 23 04	420

*All information is strictly informative