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 |
Soft | Cold-Worked | High-Strength | Soft | Cold-Worked | Soft | Hardened
and Tempered |
Hardened
and Tempered |
Stainless Steel Properties
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.
Mechanical Properties-Austenitic Grades
Bolts, Screws and Studs
Grade | Property
Class |
Tensile Strength Rm MPa
(N/mm2) minimum |
Yield Stress Rp 0.2 Mpa
(N/mm2) minimum |
Elongation AL Minimum | Diameter Range |
---|---|---|---|---|---|
A2
and A4 |
70 | 700 | 450 | 0.4d | =<M20 |
80 | 800 | 600 | 0.3d | =<M20 |
Comparison: US and ISO (DIN) Stainless Steels
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 |
Selection of Diameters - Tightening Torques, Loads
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 ForceN | Tightening Torque
Nm |
Force in service N | ||
---|---|---|---|---|---|---|
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:
**The table above is only intended as an aid for quick comparison** |
Comparative International Stainless Steel Grades
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 | |||
304S15304S16 | 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 | |||||
316S31316S33 | Z6CND17.11 | 1.44011.4436 | X8CrNiMo 17 13 | SUS316 | 14 23 4314 23 47 | 316 |
316S11316S13 | Z2CND17.12 | 1.44041.4435 | X2CrNiMo 17 12 | SUS316L | 14 23 5314 23 48 | 316L |
317S12 | Z2CND19.15 | 1.4435 | X2CrNiMo 18 16 | SUS317L | 14 23 67 | 317L |
317S16 | 1.4436 | SUS317 | 14 23 66 | 317 | ||
320S31320S33 | Z8CND17.12 | 1.45711.4573 | 14 23 50 | |||
321S31 | Z6CNT18.12 | 1.4541 | X6CrNiTi 18 11 | SUS321 | 14 23 37 | 321 |
347S31 | Z6CNNb18.11 | 1.4558 | X6CrNiNb 18 11X8CrNiNb 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 | 1.40061.4024 | X12Cr 13 | SUS410 | 13 23 02 | 410 |
410S45 | Z30C13 | X30Cr 13 | SUS420JS | 14 23 04 | 420 |
All information is strictly informative