AISI Type 302 Stainless Steel Properties, SS302 Composition, Magnetic, Density, Hardness, Equivalent
AISI Type 302 Stainless Steel (UNS S30200)
Type 302 stainless steel is basically a higher carbon version of type 304, a variant of 18-8 stainless steel. Its carbon content is ≤0.15%, and the minimum chromium content is only 1% less than 304. Grade 302 stainless steel spring wire (specified in ASTM A313) has high heat resistance and good corrosion resistance, and has excellent spring performance in the full hard or tempered condition. The main difference between SS 302, 304 and 304L is the carbon content, so there is a difference in the amount of carbide precipitation that may occur in the heat affected zone (HAZ) after heating and cooling cycles are encountered in welding. The P content of type 303 and 303Se is ≤0.20%, plus 0.15% of Se or S for free machining. These elements are not conducive to weldability and may cause severe hot cracking of the weld metal. AISI 301 has lower nickel and chromium content, so the work hardening rate is higher than AISI 302.
Datasheet & Specification
The following tables and lists give the stainless steel 302 datasheet and specification including chemical composition, physical properties and mechanical properties, heat treatment, welding, etc.
Chemical Composition
SS 302 material chemical composition is listed in the following table.
Datasheet 1, The table below shows AISI 302 chemical composition.
| Type 302 Stainless Steel Composition, % | |||||||||||
| ASTM | AISI (UNS) | C, ≤ | Si, ≤ | Mn, ≤ | P, ≤ | S, ≤ | Cr | Ni | N, ≤ | Mo, ≤ | Cu, ≤ |
| ASTM A313/A313M | 302 (UNS S30200) | 0.12 | 1.00 | 2.00 | 0.045 | 0.03 | 17.0-19.0 | 8.0-10.0 | 0.1 | – | – |
| ASTM A276/A276M; ASTM A479/A479M; ASTM A580/A580M; ASTM A314; ASTM A473 ASTM A959; | 0.15 | 1.00 | 2.00 | 0.045 | 0.03 | 17.0-19.0 | 8.0-10.0 | 0.1 | – | – | |
| ASTM A240/A240M; ASTM 666; SAE J405 | 0.15 | 0.75 | 2.00 | 0.045 | 0.03 | 17.0-19.0 | 8.0-10.0 | 0.1 | – | – | |
| SAE AMS 5688 | SAE 30302 | 0.15 | 1.00 | 2.00 | 0.04 | 0.03 | 17.0-19.0 | 8.0-10.0 | – | 0.75 | 0.75 |
Notes:
- ASTM A313/A313M: Stainless Steel Spring Wire
- ASTM A276/A276M: Standard Specification for Stainless Steel Bars and Shapes
- ASTM A240/A240M: Chromium and Chromium-Nickel Stainless Steel Plate, Sheet, and Strip for Pressure Vessels and for General Applications
- ASTM A580/A580M: Stainless Steel Wire
- ASTM A479/A479M: Stainless Steel Bars and Shapes for Use in Boilers and Other Pressure Vessels
- ASTM A959: Standard Guide for Specifying Harmonized Standard Grade Compositions for Wrought Stainless Steels
- ASTM A473: Stainless Steel Forgings
- ASTM A314: Standard Specification for Stainless Steel Billets and Bars for Forging
- ASTM 666: Annealed or Cold-Worked Austenitic Stainless Steel Sheet, Strip, Plate, and Flat Bar
- SAE J405: Chemical Composition of SAE Wrought Stainless Steels
- SAE AMS 5688: Steel, Corrosion-Resistant, Wire 18Cr-9Ni (SAE 30302) Spring Temper
AISI 302 Stainless Steel Properties
The datasheets below list grade 302 stainless steel properties including physical properties and mechanical properties.
Physical Properties
Type 302 grade stainless steel physical properties are listed in the table below such as density, melting point, specific heat, electrical resistivity, elastic modulus (modulus of elasticity), thermal conductivity, and coefficient of thermal expansion (CTE).
Datasheet 2, AISI 302 stainless steel properties – 1.
Notes:
- 10-6·K-1 = 10-6/K
- 1 Ω·mm²/m = 1 μΩ·m
- 1 g/cm3 = 1 kg/dm3 = 1000 kg/m3
- 1 GPa = 1 kN/mm2
- 1 MPa = 1 N/mm2
| Type 302 Physical Properties | |
| Density, g/cm3 (lb/in3) | 7.9 (0.289) |
| Melting point, °C (°F) | 1400-1420 (2550-2590) |
| Specific heat capacity, J/kg·K (Btu/lb ·°F) | 500 (0.12) at 20 °C (68 °F) |
| Electrical resistivity, μΩ·m | 0.72 at 20 °C (68 °F) |
| Conductivity, % IACS | 3 |
| Magnetic permeability | 1.02 (Approximate) |
| Elastic modulus (Modulus of Elasticity), Gpa (106 psi) | 193 (28) |
| Thermal conductivity, W/m·K (Btu/ft · h ·°F) | 16.2 (9.4) at 100 °C (212 °F) |
| 21.5 (12.4) at 500 °C (932 °F) | |
| Coefficient of thermal expansion (CTE), 10-6/K (μin./in. ·°F) | 17.2 (9.6) at 0-100 ℃ (32-212 °F) |
| 17.8 (9.9) at 0-315 ℃ (32-600 °F) | |
| 18.4 (10.2) at 0-538 ℃ (32-1000 °F) | |
| Acoustic properties | |||||
| Material | Density (ρ) | Sonic velocities, 105 cm/s | Acoustic impedance | ||
| g/cm3 (lb/in3) | Vl | Vt | Vs | (Zl) 106 g/cm2 · s | |
| Type 302 | 7.9 (0.29) | 5.66 | 3.12 | 3.12 | 4.47 |
| Vl- Longitudinal (compression) waves; Vt- Transverse (shear) waves; Vs- Surface waves For longitudinal waves Zl = ρVl. | |||||
SS 302 Mechanical Properties
AISI 302 stainless steel mechanical properties are given in the datasheet below including tensile strength, yield strength, elongation, reduction in area, Brinell and Rockwell hardness, etc.
Datasheet 3, Type 302 stainless steel spring wire properties – 2.
| ASTM A313 Stainless Steel Spring Wire Tensile Strength Requirements for Types 302 Class 1 and 304 | ||||
| Diameter (d), in. | Diameter (d), mm | Bend Test, Minimum Number of Bends | ksi | Mpa |
| ≤0.009 | ≤0.23 | – | 325-355 | 2240-2450 |
| 0.009<d≤0.010 | 0.23<d≤0.25 | – | 320-350 | 2205-2415 |
| 0.010<d≤0.011 | 0.25<d≤0.28 | – | 318-348 | 2190-2400 |
| 0.011<d≤0.012 | 0.28<d≤0.30 | – | 316-346 | 2180-2385 |
| 0.012<d≤0.013 | 0.30<d≤0.33 | – | 314-344 | 2165-2370 |
| 0.013<d≤0.014 | 0.33<d≤0.36 | – | 312-342 | 2150-2360 |
| 0.014<d≤0.015 | 0.36<d≤0.38 | – | 310-340 | 2135-2345 |
| 0.015<d≤0.016 | 0.38<d≤0.41 | – | 308-338 | 2125-2330 |
| 0.016<d≤0.017 | 0.41<d≤0.43 | – | 306-336 | 2110-2315 |
| 0.017<d≤0.018 | 0.43<d≤0.46 | – | 304-334 | 2095-2300 |
| 0.018<d≤0.020 | 0.46<d≤0.51 | – | 300-330 | 2070-2275 |
| 0.020<d≤0.022 | 0.51<d≤0.56 | – | 296-326 | 2040-2250 |
| 0.022<d≤0.024 | 0.56<d≤0.61 | – | 292-322 | 2015-2220 |
| 0.024<d≤0.026 | 0.61<d≤0.66 | – | 291-320 | 2005-2205 |
| 0.026<d≤0.028 | 0.66<d≤0.71 | 8 | 289-318 | 1995-2190 |
| 0.028<d≤0.031 | 0.71<d≤0.79 | 8 | 285-315 | 1965-2170 |
| 0.031<d≤0.034 | 0.79<d≤0.86 | 8 | 282-310 | 1945-2135 |
| 0.034<d≤0.037 | 0.86<d≤0.94 | 8 | 280-308 | 1930-2125 |
| 0.037<d≤0.041 | 0.94<d≤1.04 | 8 | 275-304 | 1895-2095 |
| 0.041<d≤0.045 | 1.04<d≤1.14 | 8 | 272-300 | 1875-2070 |
| 0.045<d≤0.050 | 1.14<d≤1.27 | 8 | 267-295 | 1840-2035 |
| 0.050<d≤0.054 | 1.27<d≤1.37 | 8 | 265-293 | 1825-2020 |
| 0.054<d≤0.058 | 1.37<d≤1.47 | 7 | 261-289 | 1800-1990 |
| 0.058<d≤0.063 | 1.47<d≤1.60 | 7 | 258-285 | 1780-1965 |
| 0.063<d≤0.070 | 1.60<d≤1.78 | 7 | 252-281 | 1735-1935 |
| 0.070<d≤0.075 | 1.78<d≤1.90 | 7 | 250-278 | 1725-1915 |
| 0.075<d≤0.080 | 1.90<d≤2.03 | 7 | 246-275 | 1695-1895 |
| 0.080<d≤0.087 | 2.03<d≤2.21 | 7 | 242-271 | 1670-1870 |
| 0.087<d≤0.095 | 2.21<d≤2.41 | 7 | 238-268 | 1640-1850 |
| 0.095<d≤0.105 | 2.41<d≤2.67 | 5 | 232-262 | 1600-1805 |
| 0.105<d≤0.115 | 2.67<d≤2.92 | 5 | 227-257 | 1565-1770 |
| 0.115<d≤0.125 | 2.92<d≤3.17 | 5 | 222-253 | 1530-1745 |
| 0.125<d≤0.135 | 3.17<d≤3.43 | 3 | 217-248 | 1495-1710 |
| 0.135<d≤0.148 | 3.43<d≤3.76 | 3 | 210-241 | 1450-1660 |
| 0.148<d≤0.162 | 3.76<d≤4.11 | 3 | 205-235 | 1415-1620 |
| 0.162<d≤0.177 | 4.11<d≤4.50 | 3 | 198-228 | 1365-1570 |
| 0.177<d≤0.192 | 4.50<d≤4.88 | 1 | 194-225 | 1335-1550 |
| 0.192<d≤0.207 | 4.88<d≤5.26 | 1 | 188-220 | 1295-1515 |
| 0.207<d≤0.225 | 5.26<d≤5.72 | 1 | 182-214 | 1255-1475 |
| 0.225<d≤0.250 | 5.72<d≤6.35 | 1 | 175-205 | 1205-1415 |
| 0.250<d≤0.278 | 6.35<d≤7.06 | 1 | 168-198 | 1160-1365 |
| 0.278<d≤0.306 | 7.06<d≤7.77 | 1 | 161-192 | 1110-1325 |
| 0.306<d≤0.331 | 7.77<d≤8.41 | 1 | 155186 | 1070-1280 |
| 0.331<d≤0.362 | 8.41<d≤9.19 | 1 | 150-180 | 1035-1240 |
| 0.362<d≤0.394 | 9.19<d≤10.00 | 1 | 145-175 | 1000-1205 |
| 0.394<d≤0.438 | 10.00<d≤11.12 | 1 | 140-170 | 965-1170 |
| 0.438<d≤0.500 | 11.12<d≤12.70 | 1 | 135-165 | 930-1140 |
| >0.500 | >12.70 | – | 130-160 | 895-1105 |
| When wire is specified in straightened and cut lengths, the minimum tensile strength shall be 90 % of the values listed in the table. | ||||
| ASTM A313 Tensile Strength Requirement for SS302 Class 2 | ||||
| Diameter | Cold Drawn Nominal | Stress Relieved | ||
| in. | mm | ksi (MPa) | ksi | Mpa |
| 0.050-0.160 | 1.30-4.00 | 290 (2000) | 290-340 | 2000-2345 |
| Stress relieved at 800-850°F (430-455°C) for 1/2h and air cooled. | ||||
| ASTM A276 Type 302 Stainless Steel Mechanical Properties | ||||||
| ASTM | AISI (UNS) | Tensile Strength, Mpa (ksi), ≥ | 0.2% Yield Strength, Mpa (ksi), ≥ | Elongation in 2 in. (50 mm), %, ≥ | Reduction of Area, %, ≥ | Conditions |
| ASTM A276/A276M | 302, 302B, 304, 304LN, 305, 308, 309, 309S, 309Cb, 310, 310S, 310Cb, 314, 316, 316LN, 316Cb, 316TI, 317, 321, 347, 348 | 515 (75) | 205 (30) | 40 | 50 | Annealed, Hot finished |
| 620 (90) | 310 (45) | 30 | 40 | Annealed, Cold finished, Dia ≤ 1/2 in (12.7mm) | ||
| 515 (75) | 205 (30) | 30 | 40 | Annealed, Cold finished, Dia > 1/2 in (12.7mm) | ||
| ASTM A240 Type 302 Mechanical Properties | ||||||
| ASTM | AISI (UNS) | Tensile Strength, Mpa (ksi), ≥ | 0.2% Yield Strength, Mpa (ksi), ≥ | Elongation in 2 in. (50 mm), %, ≥ | Brinell Hardness, HB, ≤ | Rockwell Hardness, HRB, ≤ |
| ASTM A240/A240M | 302 (UNS S30200) | 515 (75) | 205 (30) | 40 | 201 | 92 |
| ASTM A473 SS302 Mechanical Properties | ||||||
| ASTM | AISI (UNS) | Tensile Strength, Mpa (ksi), ≥ | 0.2% Yield Strength, Mpa (ksi), ≥ | Elongation in 2 in. (50 mm), %, ≥ | Reduction of Area, %, ≥ | Conditions |
| ASTM A473/A473M | 302 (UNS S30200) | 515 (75) | 205 (30) | 40 | 50 | Annealed |
| ASTM A479 SS302 Mechanical Properties | ||||||
| ASTM | AISI (UNS) | Tensile Strength, Mpa (ksi), ≥ | 0.2% Yield Strength, Mpa (ksi), ≥ | Elongation in 2 in. (50 mm), %, ≥ | Reduction of Area, %, ≥ | Conditions |
| ASTM A479/A479M | 302 (UNS S30200) | 515 (75) | 205 (30) | 30 | 40 | Annealed |
| ASTM A580 Type 302 Mechanical Properties | ||||||
| ASTM | AISI (UNS) | Tensile Strength, Mpa (ksi), ≥ | 0.2% Yield Strength, Mpa (ksi), ≥ | Elongation in 2 in. (50 mm), %, ≥ | Reduction of Area, %, ≥ | Conditions |
| ASTM A580/A580M | 302 (UNS S30200), 302B (UNS S30215) | 620 (90) | 310 (45) | 30 | 40 | Annealed, cold finished |
| 515 (75) | 205 (30) | 35 | 50 | Annealed | ||
| ASTM A666 302 Mechanical Properties | |||||||
| ASTM | AISI Type (UNS) | Conditions | Tensile Strength, MPa (ksi), ≥ | 0.2% Yield Strength, MPa (ksi), ≥ | Elongation in 50 mm (2 in.), %, ≥ | Brinell Hardness (HB), ≤ | Rockwell Hardness (HRB), ≤ |
| ASTM A666 | 302 (UNS S30200) | Annealed | 517 (75) | 205 (30) | 40 | 201 | 92 |
| Full Hard | 1275 (185) | 965 (140) | 3 (<0.015 in.); 4 (≥ 0.015 in) | ||||
| 1/2 Hard (Half Hard) | 1035 (150) | 760 (110) | 9 (<0.015 in); 10 (≥ 0.015 in) | ||||
| 3/4 Hard | 1205 (175) | 930 (135) | 5 (<0.015 in); 6 (≥ 0.015 in) | ||||
| 1/4 (Quarter-hard) Hard | 862 (125) | 517 (75) | 10 (≤ 0.03 in); 12 (> 0.03 in) | ||||
| 1/8 Hard | 690 (100) | 380 (55) | 35 | ||||
| 302 plate, strip, sheet | 1/16 Hard | 585 (85) | 310 (45) | 40 | |||
| 302 flat bar | 620 (90) | 310 (45) | 40 (>0.030 in) | ||||
Type 302 Grade Stainless Steel Heat Treatment
- SS 302 annealing temperature is 1010-1120 °C (1850-2050 °F), recommended temperature is 1400 °C (1900 °F)
- Oven stress-relief temperature and time for wire: 345 °C (650 °F), 30 minutes.
- Typical stress relief temperature for SS302 steel spring wire: 425-480 °C (800-900 °F) based on 30 min at temperature, only suitable for stress relief after coiling and not valid for stress relieving after shot peening. When the spring is to be used at a high temperature, the stress relief temperature should be close to the upper limit of this range to minimize relaxation in use. Otherwise, lower temperature are better.
- SS 302 typical forging temperature range is 925-1260 °C (1700-2300 °F).
Welding
SS 302 may be readily welded by friction welding, seam welding and flash welding process; arc welding not recommended. If a filler metal is required, E/ER308 or E/ER308L is recommended.
Heat Resistance
Maximum service temperatures in air
- Intermittent service: 870 °C (1600 °F)
- Continuous service: 925 °C (1700 °F)
Corrosion Resistance
| Corrosion of AISI 302 stainless steel in marine environment | |||
| AISI Type | Average corrosion rate, mm/year | Average depth of pits, mm (mils) | Appearance |
| 302 | <2.5 x 10-5 | 0.03 (1.2) | Spotted with rust stain on 10% of surface |
Applications
AISI 302 stainless steel is widely used in industrial and architectural industries, such as stamping, steel springs, wire rope, metal mesh, woven wire mesh, screen mesh, stainless steel decorative mesh, perforated metal sheet, steel mesh, metal filter and strainer, steel washer, handrail, etc.
SS 302 Equivalent Material
Grade 302 stainless steel equivalent to European EN standard (Germany DIN EN, British BSI…), Chinese GB, ISO, and Japanese JIS, etc.
| AISI 302 Equivalent Material | |||||||||||||||||||
| US | European | China | Japan | ISO | Australia | India | Rusia | Korea | |||||||||||
| Standard | Grade (UNS) | Standard | Grade | Standard | Name (Steel Number) | Standard | Name [UNS] | Standard | Grade | Standard | Name (ISO Number) | Standard | Grade | Standard | Grade | Standard | Grade | Standard | Grade |
| AISI, SAE; ASTM | 302 (UNS S30200) | SAE AMS 5688 | 18Cr-9Ni (SAE 30302) | EN 10088-1; EN 10088-2; EN 10088-3 | X9CrNi18-9 (1.4325) | GB/T 1220; GB/T 3280 | 1Cr18Ni9; 12Cr18Ni9 (New designation); [S30210] | JIS G4304; JIS G4304; JIS G4305 | SUS302 | ISO 15510 | X9CrNi18-9 (4325-302-00-E) | ||||||||
| 302B (UNS S30215) | X12CrNiSi18-9-3 (1.4326) | 1Cr18Ni9Si3; 12Cr18Ni9Si3 (New designation); [S30240] | SUS302B | X12CrNiSi18-9-3 (4326-302-15-I) | |||||||||||||||
Related material: Duplex 2205, 1.4541 (X6CrNiTi18-10), 6061 Aluminum, AISI 430, 1.4310 (X10CrNi18-8), 1.4301 (X5CrNi18-10)
