1. Comparative Properties of 201/202/304/430 Stainless Steel

2. Classification of Stainless Steels

3. AusteniticFerritic Cr-NiCr-Mn(-Ni)Cr 430ˇ 304ˇ 201ˇ 202ˇ

4. Chemical Composition (ASTM A240) TypeCSiMnPSCrNiCuN 304 ≦ 0.08 ≦ 0.75 ≦ 2.00 ≦ 0.045 ≦ 0.03 18.00 ~20.00 8.00 ~10.5 － ≦ 0.10 430 ≦ 0.12 ≦ 1.00 ≦ 0.040 ≦ 0.03 17.00 ~19.00 ≦ 0.50 － ≦ 0.030 TE 201 0.0450.459.50.060.011511.750.17 TE 202 0.0450.457.50.060.011541.50.1 201 ≦ 0.15 ≦ 1.00 5.5 ~7.5 ≦ 0.06 ≦ 0.03 16.00 ~18.00 3.5 ~5.5 － ≦ 0.25 202 ≦ 0.15 ≦ 1.00 7.5 ~10.0 ≦ 0.06 ≦ 0.03 17.00 ~19.00 4.0 ~6.0 － ≦ 0.25

5. The Function of Cu Austenite stabilizer. Improving formability. Improving corrosion resistance. Impairing tensile strength and yield stress. Impairing work hardenability.

6. Corrosion Resistance 405 430 20Cb-3 Custom 455 410 420 304 316 440C 431 Custom 450 Serious Corrosion Chemical Corrosion Medium Corrosion Industry polluted air Clean air Yield Strength (MPa) 350 1225 1750 Corrosion Resistance 202 201

7. Corrosion Resistance TypeMajor CompositionCorrosion Resistance 304 18Cr-8Ni-2.0Mn-0.08C 1 Good in a wide variety of environments and uniform corrosion TE202 15Cr-4Ni-7.5Mn-1.5Cu-0.1N 2 Low Ni and add Cu, corrosion resistance lower than 304. TE201 15Cr-1Ni-9.5Mn-1.75Cu-0.17N 3 Low Cr, Ni, lower corrosion resistance 430 17Cr-0.12C 4 Good in stress corrosion, lower in other corrosion resistances.

8. Weldability TypeMajor CompositionWeldability 304 18Cr-8Ni-2.0Mn-0.08C 1 Excellent weldability TE202 15Cr-4Ni-7.5Mn-1.5Cu-0.1N 2 Good weldability TE201 15Cr-1Ni-9.5Mn-1.75Cu-0.17N 2 Good weldability 430 17Cr-0.12C 4 Fair weldability

9. Mechanical Properties (ASTM A240) Type Tensile Strength Yield Strength n valueElongationHardness MPa －％ HBHRB 304 ≧ 515 ≧ 205 0.47 ≧ 40 ≦ 201 ≦ 92 430 ≧ 450 ≧ 205 0.2 ≧ 22 ≦ 183 ≦ 89 TE201727~763333~360 － 53~55 183~2 00 89~91 TE202607~627294 － 53~55 162~1 71 85~87 201 ≧ 655 ≧ 310 0.49 ≧ 40 ≦ 241 100 202 ≧ 620 ≧ 260 0.45 ≧ 40 ≦ 241 －

10. Formability Forming201TE201202TE202304430 BlankingBBBBBA Brake FormingBBAAA A＊A＊ Coining B－CB－CB－CB－C BBBA Deep Drawing A－BA－BA－BA－B AAA A－BA－B Embossing B－CB－CB－CB－C BBBA Cold Heading C－DC－D CCCCA Hot HeadingBBBBBB Magnetic ★★ ★★★ YES PunchingCCBBB A－BA－B Roll FormingBBAAAA SawingCCCCCB Spinning C－DC－D C B－CB－C BBA n value0.49 － 0.45 － 0.470.2 A ＝ Excellent ★＝ After heavy cold work have magnetism B ＝ Good ★★＝ After middle cold work have magnetism C ＝ Fair ＊ ＝ Severe sharp bends should be avoided D ＝ Not generally recommended 【 n value ： Work hardening index 】

11. Formability TypeMajor CompositionFormability 304 18Cr-8Ni-2.0Mn-0.08C 2 Good machinability TE202 15Cr-4Ni-7.5Mn-1.5Cu-0.1N 2 Add Cu, Improving workability TE201 15Cr-1Ni-9.5Mn-1.75Cu-0.17N 4 Higher intensity, low formability and workability 430 17Cr-0.12C 1 Lower strength, forming easily

12. Mill Finishes Type Sheet Strip UnpolishedPolish 304/3162D, 2B3,4,6,7,81,2 4302D, 2B3,41,2 2012D, 2B3,4,6,7,81,2 2022D, 2B3,4,6,7,81,2 Red means evaluated data Hardness ： 201 ＞ 202 ＞ 304 ＞ 430(higher hardness is good for polishing ) 【 Reference ： ASM HANDBOOK 】

13. Mill Finishes Type Major Composition Mill Finishes 304 18Cr-8Ni- 2.0Mn-0.08C 3 TE 202 15Cr-4Ni- 7.5Mn-1.5Cu- 0.1N 2 TE 201 15Cr-1Ni- 9.5Mn-1.75Cu- 0.17N 1 430 17Cr-0.12C 4 FinishesDescription NO.1 A rough, dull surface that results from hot rolling to the specified thickness followed by annealing and descaling. NO.2D Those finished, after cold rolling, by heat treatment, pickling or other equivalent treatment. NO.2B Those finished, after cold rolling, by heat treatment, pickling or other equivalent treatment and lastly by cold rolling to give an appropriate luster. NO.3 An intermediate polished surface obtained by finishing with a 100-grit abrasive. NO.4 A polished surface obtained by finishing with a 120 to 150-mesh abrasive. NO.6 A dull satin finish having lower reflectivity than No.4 finish. NO.7 A highly reflective finish.(not to the extent of completely removing the grit lines) NO.8 The most reflective surface. (completely removing the grit lines)

14. General Characteristics TypeMajor CompositionGeneral Characteristics 304 18Cr-8Ni-2.0Mn-0.08C Good in corrosion resistance, oxidation resistance, formability and weldability. TE202 15Cr-4Ni-7.5Mn-1.5Cu-0.1N Instead of 302 low Ni steels, cold work hardenability very fast. TE201 15Cr-1Ni-9.5Mn-1.75Cu-0.17N Higher tensile strength and yield stress, because it contents higher percent carbon and nitrogen. 430 17Cr-0.12C Magnetic, can not quench hardening, 475 ℃ brittlement.

15. TypeMajor CompositionApplication 304 18Cr-8Ni-2.0Mn-0.08C Housewares, Building construction 、 Industry Pipe, Cookware, General purpose TE202 15Cr-4Ni-7.5Mn-1.5Cu-0.1N Housewares, The interior of the house, Cookware, General purpose TE201 15Cr-1Ni-9.5Mn-1.75Cu-0.17N Containers, Railroad vehicles, Mechanical tubing in dry condition 430 17Cr-0.12C Kitchen utensils, Dinnerware, Accessories Applications

16. Conclusion Type TE201TE202304430 Reference Microstructure AusteniticAustenite Ferritic Chemical Composition Ni ％ LowMediumHighN/A Chemical Composition Corrosion Resistance MediumSimilar to 304HighMedium Chemical Composition Weldability High Very HighLow Chemical Composition Strength Very HighHighMediumLow Mechanical Properties Formability LowSimilar to 304High Very High Mechanical Properties Mill Finishes Very High Medium Mechanical Properties Magnetic Generally No Yes Chemical Composition Cost LowMediumHighLow Chemical Composition Application LowSimilar to 304HighmediumBoth