Jump to content

SAE steel grades

From Wikipedia, the free encyclopedia
(Redirected from AISI steel grades)
Steels
Phases
Microstructures
Classes
Other iron-based materials

The SAE steel grades system is a standard alloy numbering system (SAE J1086 – Numbering Metals and Alloys) for steel grades maintained by SAE International.

In the 1930s and 1940s, the American Iron and Steel Institute (AISI) and SAE were both involved in efforts to standardize such a numbering system for steels. These efforts were similar and overlapped significantly. For several decades the systems were united into a joint system designated the AISI/SAE steel grades. In 1995 the AISI turned over future maintenance of the system to SAE because the AISI never wrote any of the specifications.[1]

Today steel quotes and certifications commonly make reference to both SAE and AISI, not always with precise differentiation. For example, in the alloy/grade field, a certificate might refer to "4140", "AISI 4140", or "SAE 4140", and in most light-industrial applications any of the above is accepted as adequate, and considered equivalent, for the job at hand, as long as the specific specification called out by the designer (for example, "4140 bar per ASTM-A108" or "4140 bar per AMS 6349") is certified to on the certificate. The alloy number is simply a general classifier, whereas it is the specification itself that narrows down the steel to a very specific standard.

The SAE steel grade system's correspondence to other alloy numbering systems, such as the ASTM-SAE unified numbering system (UNS), can be seen in cross-referencing tables (including the ones given below).

The AISI system uses a letter prefix to denote the steelmaking process. The prefix "C" denotes open-hearth furnace, electric arc furnace or basic oxygen furnace steels, while "E" specifies only electric arc furnace steel.[2][3] A letter "L" within the grade name indicates lead as an added ingredient; for example, 12L14 is a common grade that is 1214 with lead added for machinability.

Suffixes may be added to the steel grade which specify the forming process used to create a part. These may include cold working (CDS), hot working (HR), quenching and tempering (Q&T), and other methods.

Carbon steel

[edit]
Main articles: Carbon steel and Alloy steel

Carbon steels and alloy steels are designated a four digit number, whereby the first digit indicates the main alloying element(s), the second digit indicates tg (top grade) element(s), and the last two digits indicate the amount of carbon, in hundredths of a percent (basis points) by weight. For example, a 1060 steel is a plain-carbon steel containing 0.60 wt% C.[4]

An "H" suffix can be added to any designation to denote hardenability is a major requirement. The chemical requirements are loosened but hardness values defined for various distances on a Jominy test.[3]

Major classifications of steel[2]
SAE designation Type
1xxx Carbon steels
2xxx Nickel steels
3xxx Nickel-chromium steels
4xxx Molybdenum steels
5xxx Chromium steels
6xxx Chromium-vanadium steels
7xxx Tungsten steels
8xxx Nickel-chromium-molybdenum steels
9xxx Silicon-manganese steels
Carbon and alloy steel grades[5]
SAE designation Type, and composition by weight
Carbon steels
10xx Plain carbon (Mn 1.00% max.)
11xx Resulfurized
12xx Resulfurized and rephosphorized
15xx Plain Carbon (Mn 1.00–1.65% max.)
15Bxx Plain Carbon with Boron (Mn 1.00–1.65% max., B 0.0005-0.003% max.)
Manganese steels
13xx Mn 1.75%
Nickel steels
23xx Ni 3.50%
25xx Ni 5.00%
Nickel-chromium steels
31xx Ni 1.25%; Cr 0.65%, or 0.80%
32xx Ni 1.75%; Cr 1.07%
33xx Ni 3.50%; Cr 1.50%, or 1.57%
34xx Ni 3.00%; Cr 0.77%
Molybdenum steels
40xx Mo 0.20%, 0.25%, or Mo 0.25% and S 0.042%[1]
44xx Mo 0.40%, or 0.52%
Chromium-molybdenum (chromoly) steels
41xx Cr 0.50%, 0.80%, or 0.95%; Mo 0.12%, 0.20%, 0.25%, or 0.30%
Nickel-chromium-molybdenum steels
43xx Ni 1.82%; Cr 0.50–0.80%; Mo 0.25%
43BVxx Ni 1.82%; Cr 0.50%; Mo 0.12%, or 0.35%; V 0.03% min
47xx Ni 1.05%; Cr 0.45%; Mo 0.20%, or 0.35%
81xx Ni 0.30%; Cr 0.40%; Mo 0.12%
81Bxx Ni 0.30%; Cr 0.45%; Mo 0.12%; and added boron[1]
86xx Ni 0.55%; Cr 0.50%; Mo 0.20%
87xx Ni 0.55%; Cr 0.50%; Mo 0.25%
88xx Ni 0.55%; Cr 0.50%; Mo 0.35%
93xx Ni 3.25%; Cr 1.20%; Mo 0.12%
94xx Ni 0.45%; Cr 0.40%; Mo 0.12%
97xx Ni 0.55%; Cr 0.20%; Mo 0.20%
98xx Ni 1.00%; Cr 0.80%; Mo 0.25%
Nickel-molybdenum steels
46xx Ni 0.85%, or 1.82%; Mo 0.20%, or 0.25%
48xx Ni 3.50%; Mo 0.25%
Chromium steels
50xx Cr 0.27%, 0.40%, 0.50%, or 0.65%
50xxx Cr 0.50%; C 1.00% min
50Bxx Cr 0.28%, or 0.50%; and added boron[1]
51xx Cr 0.80%, 0.87%, 0.92%, 1.00%, or 1.05%
51xxx Cr 1.02%; C 1.00% min.
51Bxx Cr 0.80%; and added boron[1]
52xxx Cr 1.45%; C 1.00% min.
Chromium-vanadium steels
61xx Cr 0.60%, 0.80%, 0.95%; V 0.10%, or 0.15% min.
Tungsten-chromium steels
72xx W 1.75%; Cr 0.75%
Silicon-manganese steels
92xx Si 1.40%, or 2.00%; Mn 0.65%, 0.82%, or 0.85%; Cr 0.00%, or 0.65%
High-strength low-alloy steels
9xx Various SAE grades
xxBxx Boron steels
xxLxx Leaded steels

Stainless steel

[edit]
Main article: Stainless steel

Stainless steels, on the other hand, are designated with three-digit numbers. Unlike carbon and alloy steel grades, the last two digits do not represent the carbon content.

100 Series

[edit]
  • Type 102—austenitic general purpose stainless steel

200 Series—austenitic chromium-nickel-manganese alloys

[edit]
  • Type 201— austenitic that is hardenable

300 Series—austenitic chromium-nickel alloys

[edit]
Schaeffler diagram
  • Type 301—highly ductile, for formed products. Also hardens rapidly during mechanical working. Good weldability. Better wear resistance and fatigue strength than 304.
  • Type 302—same corrosion resistance as 304, with slightly higher strength due to additional carbon.
  • Type 303—free machining version of 304 via addition of sulfur and phosphorus. Also referred to as "A1" in accordance with ISO 3506.[6]
  • Type 304—the most common grade; the classic 18/8 (18% chromium, 8% nickel) stainless steel. Outside of the US it is commonly known as "A2 stainless steel", in accordance with ISO 3506 (not to be confused with A2 tool steel).[6] The Japanese equivalent grade of this material is SUS304.
  • Type 304L—same as the 304 grade but lower carbon content to increase weldability. Is slightly weaker than 304.
  • Type 304LN—same as 304L, but also nitrogen is added to obtain a much higher yield and tensile strength than 304L.
  • Type 305—same as 304, but with more nickel to decrease work hardening.
  • Type 308—used as the filler metal when welding 304.
  • Type 309—better temperature resistance than 304, also sometimes used as filler metal when welding dissimilar steels, along with inconel.
  • Type 310 310S— is a highly alloyed austenitic stainless steel used for high temperature application. The high chromium and nickel content give the steel excellent oxidation resistance as well as high strength at high temperature. This grade is also very ductile, and has good weldability enabling its widespread usage in many applications. [7]
  • Type 316—the second most common grade (after 304); for food and surgical stainless steel uses; alloy addition of molybdenum prevents specific forms of corrosion. It is also known as marine grade stainless steel due to its increased resistance to chloride corrosion compared to type 304. 316 is often used for building nuclear reprocessing plants.
  • Type 316L—is an extra low carbon grade of 316, generally used in stainless steel watches and marine applications, as well exclusively in the fabrication of reactor pressure vessels for boiling water reactors, due to its high resistance to corrosion. Also referred to as "A4" in accordance with ISO 3506.[6]
  • Type 316LN—same as 316L with nitrogen added to obtain a higher yield and tensile strength than 316L.
  • Type 316Ti—variant of type 316 that includes titanium for heat resistance. It is used in flexible chimney liners.
  • Type 317[8]
  • Type 321—similar to 304 but lower risk of weld decay due to addition of titanium.
  • Type 347,[8] with addition of niobium for desensitization during welding.

400 Series—ferritic and martensitic chromium alloys

[edit]
  • Type 405—ferritic for welding applications
  • Type 408—heat-resistant; poor corrosion resistance; 11% chromium, 8% nickel.
  • Type 409—cheapest type; used for automobile exhausts; ferritic (iron/chromium only).
  • Type 410—martensitic (high-strength iron/chromium). Wear-resistant, but less corrosion-resistant.[9]
  • Type 416—easy to machine due to additional sulfur
  • Type 420—Cutlery Grade martensitic; similar to the Brearley's original rustless steel. Excellent polishability.
  • Type 430—decorative, e.g., for automotive trim; ferritic. Good formability, but with reduced temperature and corrosion resistance.
  • Type 439—ferritic grade, a higher grade version of 409 used for catalytic converter exhaust sections. Increased chromium for improved high temperature corrosion/oxidation resistance.
  • Type 440—a higher grade of cutlery steel, with more carbon, allowing for much better edge retention when properly heat-treated. It can be hardened to approximately Rockwell 58 hardness, making it one of the hardest stainless steels. Due to its toughness and relatively low cost, most display-only and replica swords or knives are made of 440 stainless. Available in four grades:
    • Type 440A—has the least amount of carbon making this the most stain-resistant.
    • Type 440B—slightly more carbon than 440A.
    • Type 440C—has the greatest amount of carbon of the type 440 variants. Strongest and considered more desirable in knifemaking than the Type 440A variant[citation needed], except for diving or other salt-water applications. This variant is also more readily available than other variants of type 440.[10]
    • Type 440F—a free-machining variant. Contains the same high carbon content as type 440C.
  • Type 446—ferritic designed for elevated temperature service and is capable of tolerating molten copper and brass. [11]

500 Series—heat-resisting chromium alloys

[edit]

600 Series—originally created for proprietary alloys (which are no longer given SAE grade numbers)[12]

[edit]
  • 601 through 604: Martensitic low-alloy steels.
  • 610 through 613: Martensitic secondary hardening steels.
  • 614 through 619: Martensitic chromium steels.
  • 630 through 635: Semiaustenitic and martensitic precipitation hardening stainless steels.
    • Type 630 is most common PH stainless, better known as 17-4; 17% chromium, 4% nickel.
  • 650 through 653: Austenitic steels strengthened by hot/cold work.
  • 660 through 665: Austenitic superalloys; all grades except alloy 661 are strengthened by second-phase precipitation.

900 series—austenitic chromium-molybdenum alloys

[edit]
  • Type 904—similar to 316 but with higher chromium and molybdenum content for more corrosion resistance

Stainless steel designations table

[edit]
Stainless steel designations[13]
Designation Composition by weight (%)
SAE UNS Cr Ni C Mn Si P S N Other
Austenitic
201 S20100 16–18 3.5–5.5 0.15 5.5–7.5 0.75 0.06 0.03 0.25 -
202 S20200 17–19 4–6 0.15 7.5–10.0 0.75 0.06 0.03 0.25 -
205 S20500 16.5–18 1–1.75 0.12–0.25 14–15.5 0.75 0.06 0.03 0.32–0.40 -
254[14] S31254 20 18 0.02 max. - - - - 0.20 6 Mo; 0.75 Cu; "Super austenitic"; All values nominal
301 S30100 16–18 6–8 0.15 2 0.75 0.045 0.03 - -
302 S30200 17–19 8–10 0.15 2 0.75 0.045 0.03 0.1 -
302B S30215 17–19 8–10 0.15 2 2.0–3.0 0.045 0.03 - -
303 S30300 17–19 8–10 0.15 2 1 0.2 0.15 min. - Mo 0.60 (optional)
303Se S30323 17–19 8–10 0.15 2 1 0.2 0.06 - 0.15 Se min.
304 S30400 18–20 8–10.50 0.08 2 0.75 0.045 0.03 0.1 -
304L S30403 18–20 8–12 0.03 2 0.75 0.045 0.03 0.1 -
304Cu S30430 17–19 8–10 0.08 2 0.75 0.045 0.03 - 3–4 Cu
304N S30451 18–20 8–10.50 0.08 2 0.75 0.045 0.03 0.10–0.16 -
305 S30500 17–19 10.50–13 0.12 2 0.75 0.045 0.03 - -
308 S30800 19–21 10–12 0.08 2 1 0.045 0.03 - -
309 S30900 22–24 12–15 0.2 2 1 0.045 0.03 - -
309S S30908 22–24 12–15 0.08 2 1 0.045 0.03 - -
310 S31000 24–26 19–22 0.25 2 1.5 0.045 0.03 - -
310S S31008 24–26 19–22 0.08 2 1.5 0.045 0.03 - -
314 S31400 23–26 19–22 0.25 2 1.5–3.0 0.045 0.03 - -
316 S31600 16–18 10–14 0.08 2 0.75 0.045 0.03 0.10 2.0–3.0 Mo
316L S31603 16–18 10–14 0.03 2 0.75 0.045 0.03 0.10 2.0–3.0 Mo
316F S31620 16–18 10–14 0.08 2 1 0.2 0.10 min. - 1.75–2.50 Mo
316N S31651 16–18 10–14 0.08 2 0.75 0.045 0.03 0.10–0.16 2.0–3.0 Mo
317 S31700 18–20 11–15 0.08 2 0.75 0.045 0.03 0.10 max. 3.0–4.0 Mo
317L S31703 18–20 11–15 0.03 2 0.75 0.045 0.03 0.10 max. 3.0–4.0 Mo
321 S32100 17–19 9–12 0.08 2 0.75 0.045 0.03 0.10 max. Ti 5(C+N) min., 0.70 max.
329 S32900 23–28 2.5–5 0.08 2 0.75 0.04 0.03 - 1–2 Mo
330 N08330 17–20 34–37 0.08 2 0.75–1.50 0.04 0.03 - -
347 S34700 17–19 9–13 0.08 2 0.75 0.045 0.030 - Nb + Ta, 10 × C min., 1 max.
348 S34800 17–19 9–13 0.08 2 0.75 0.045 0.030 - Nb + Ta, 10 × C min., 1 max., but 0.10 Ta max.; 0.20 Ca
384 S38400 15–17 17–19 0.08 2 1 0.045 0.03 - -
Designation Composition by weight (%)
SAE UNS Cr Ni C Mn Si P S N Other
Ferritic
405 S40500 11.5–14.5 - 0.08 1 1 0.04 0.03 - 0.1–0.3 Al, 0.60 max.
409 S40900 10.5–11.75 0.05 0.08 1 1 0.045 0.03 - Ti 6 × (C + N) [15]
429 S42900 14–16 0.75 0.12 1 1 0.04 0.03 - -
430 S43000 16–18 0.75 0.12 1 1 0.04 0.03 - -
430F S43020 16–18 - 0.12 1.25 1 0.06 0.15 min. - 0.60 Mo (optional)
430FSe S43023 16–18 - 0.12 1.25 1 0.06 0.06 - 0.15 Se min.
434 S43400 16–18 - 0.12 1 1 0.04 0.03 - 0.75–1.25 Mo
436 S43600 16–18 - 0.12 1 1 0.04 0.03 - 0.75–1.25 Mo; Nb+Ta 5 × C min., 0.70 max.
442 S44200 18–23 - 0.2 1 1 0.04 0.03 - -
446 S44600 23–27 0.25 0.2 1.5 1 0.04 0.03 - -
Designation Composition by weight (%)
SAE UNS Cr Ni C Mn Si P S N Other
Martensitic
403 S40300 11.5–13.0 0.60 0.15 1 0.5 0.04 0.03 - -
410 S41000 11.5–13.5 0.75 0.15 1 1 0.04 0.03 - -
414 S41400 11.5–13.5 1.25–2.50 0.15 1 1 0.04 0.03 - -
416 S41600 12–14 - 0.15 1.25 1 0.06 0.15 min. - 0.060 Mo (optional)
416Se S41623 12–14 - 0.15 1.25 1 0.06 0.06 - 0.15 Se min.
420 S42000 12–14 - 0.15 min. 1 1 0.04 0.03 - -
420F S42020 12–14 - 0.15 min. 1.25 1 0.06 0.15 min. - 0.60 Mo max. (optional)
422 S42200 11.0–12.5 0.50–1.0 0.20–0.25 0.5–1.0 0.5 0.025 0.025 - 0.90–1.25 Mo; 0.20–0.30 V; 0.90–1.25 W
431 S41623 15–17 1.25–2.50 0.2 1 1 0.04 0.03 - -
440A S44002 16–18 - 0.60–0.75 1 1 0.04 0.03 - 0.75 Mo
440B S44003 16–18 - 0.75–0.95 1 1 0.04 0.03 - 0.75 Mo
440C S44004 16–18 - 0.95–1.20 1 1 0.04 0.03 - 0.75 Mo
Designation Composition by weight (%)
SAE UNS Cr Ni C Mn Si P S N Other
Heat resisting
501 S50100 4–6 - 0.10 min. 1 1 0.04 0.03 - 0.40–0.65 Mo
502 S50200 4–6 - 0.1 1 1 0.04 0.03 - 0.40–0.65 Mo
Martensitic precipitation hardening
630 S17400 15–17 3–5 0.07 1 1 0.04 0.03 - Cu 3–5, Ta 0.15–0.45 [16]

High-strength low-alloy steel

[edit]
Main article: High-strength low-alloy steel

See also

[edit]

References

[edit]
  1. ^ a b c d e Bringas, John E. (2004). Handbook of Comparative World Steel Standards: Third Edition (PDF) (3rd ed.). ASTM International. p. 14. ISBN 0-8031-3362-6. Archived from the original (PDF) on January 27, 2007.
  2. ^ a b Jeffus 2002, p. 635.
  3. ^ a b Degarmo, Black & Kohser 2003, p. 115.
  4. ^ Degarmo, Black & Kohser 2003, p. 113.
  5. ^ Oberg 2004, p. 443.
  6. ^ a b c "Stainless Steel Fasteners". Australian Stainless Steel Development Association. Archived from the original on 2007-09-29. Retrieved 2007-08-13.
  7. ^ "310 310S Stainless Steel". TubingChina.com Stainless Steel Directory. Retrieved 2015-09-18.
  8. ^ a b Guiraldenq, Pierre; Hardouin Duparc, Olivier (2017). "The genesis of the Schaeffler diagram in the history of stainless steel". Metallurgical Research & Technology. 114 (6): 613. Bibcode:2017MetRT.114..613G. doi:10.1051/metal/2017059.
  9. ^ "410 Stainless Steel - ASMG Trading". www.asmgtrading.com.
  10. ^ "440A, 440B, 440C, 440F, 440F Se HARDENABLE CHROMIUM STAINLESS STEEL". AMS Resources. 16 March 2014. Retrieved 12 June 2015.
  11. ^ "446 Stainless Steel - ASMG Trading". www.asmgtrading.com. Retrieved 2021-11-15.
  12. ^ Cobb, Harold (September 2007). "The Naming and Numbering of Stainless Steels". Advanced Materials & Processes: 39–44.[permanent dead link]
  13. ^ Oberg 2004, pp. 448–49.
  14. ^ "What is Stainless Steel?". Nickel Institute. Archived from the original on 2005-12-31. Retrieved 2007-08-13.
  15. ^ "section 2, part A:Standard specification for chromium and chromium-nickel stainless steel plate, sheet, and strip for pressure vessels and for general applications". ASTM A SA-240/SA-540M. 2007. p. 385.
  16. ^ "Precipitation-Hardening Stainless Steel Type 17-4PH (S17400)" (PDF).

Bibliography

[edit]
Retrieved from "https://en.wikipedia.org/w/index.php?title=SAE_steel_grades&oldid=1239429091"