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title: "Unalloyed structural steels — 452 grades with composition"
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![Unalloyed structural steels](/images/uploads/41c1ace7-f92a-486f-bf5b-dbee84fc846d/structural-steel-category-hot-rolled-plate-and-section-1920x1080.jpg)

Category · 452 grades

# Unalloyed structural steels

Unalloyed structural steels include all low-carbon steels in which the iron companions do not exceed specified minimum values. The yield strength, formability and weldability are the decisive factors for their use. They are soft, pliable, tough and stretchy, but cannot be hardened by heat treatment.

| Grade | Material no. | P | S | C | Mn | Si | Al |
|---|---|---|---|---|---|---|---|
| [STS480](/materials/jis/sts480 "STS480") | — | max 0.035 | max 0.035 | max 0.33 | 0.3 - 1.5 | 0.1 - 0.35 | — |
| [STKM13A](/materials/jis/stkm13a "STKM13A") | — | max 0.04 | max 0.04 | max 0.25 | 0.3 - 0.9 | max 0.35 | — |
| [SR300](/materials/ks/sr300 "SR300") | — | max 0.05 | max 0.05 | — | — | — | — |
| [SGD1](/materials/jis/sgd1 "SGD1") | — | max 0.045 | max 0.045 | max 0.1 | 0.3 - 0.6 | — | — |
| [STKM14B](/materials/jis/stkm14b "STKM14B") | — | max 0.04 | max 0.04 | max 0.3 | 0.3 - 1 | max 0.35 | — |
| [SD500](/materials/ks/sd500 "SD500") | — | max 0.05 | max 0.05 | — | — | — | — |
| [STK490](/materials/jis/stk490 "STK490") | — | max 0.035 | max 0.035 | max 0.18 | max 1.65 | max 0.55 | — |
| [SNR400A](/materials/jis/snr400a "SNR400A") | — | max 0.05 | max 0.05 | max 0.24 | — | — | — |
| [STKM16A](/materials/jis/stkm16a "STKM16A") | — | max 0.04 | max 0.04 | 0.35 - 0.45 | 0.4 - 1 | max 0.4 | — |
| [SD700](/materials/ks/sd700 "SD700") | — | — | — | — | — | — | — |
| [SM520C](/materials/jis/sm520c "SM520C") | — | max 0.035 | max 0.035 | max 0.2 | max 1.6 | max 0.55 | — |
| [SR295](/materials/jis/sr295 "SR295") | — | max 0.05 | max 0.05 | — | — | — | — |
| [STKM18A](/materials/jis/stkm18a "STKM18A") | — | max 0.04 | max 0.04 | max 0.18 | max 1.5 | max 0.55 | — |
| [SPS500](/materials/ks/sps500 "SPS500") | — | max 0.04 | max 0.04 | max 0.24 | 0.3 - 1.3 | max 0.35 | — |
| [STAM290GB](/materials/jis/stam290gb "STAM290GB") | — | max 0.035 | max 0.035 | max 0.12 | max 0.6 | max 0.35 | — |
| [SFB2](/materials/jis/sfb2 "SFB2") | — | max 0.03 | max 0.035 | 0.1 - 0.25 | 0.3 - 1.2 | 0.15 - 0.5 | — |
| [STKM19C](/materials/jis/stkm19c "STKM19C") | — | max 0.04 | max 0.04 | max 0.25 | max 1.5 | max 0.55 | — |
| [SWP600](/materials/ks/swp600 "SWP600") | — | max 0.04 | max 0.04 | max 0.25 | — | — | — |
| [STAM470G](/materials/jis/stam470g "STAM470G") | — | max 0.035 | max 0.035 | max 0.25 | 0.3 - 0.9 | max 0.35 | — |
| [SFB6](/materials/jis/sfb6 "SFB6") | — | max 0.03 | max 0.035 | 0.35 - 0.5 | 0.5 - 1.2 | 0.15 - 0.5 | — |
| [STC510B](/materials/jis/stc510b "STC510B") | — | max 0.04 | max 0.04 | max 0.18 | max 1.5 | max 0.55 | — |
| [SPPH420](/materials/ks/spph420 "SPPH420") | — | max 0.035 | max 0.035 | max 0.3 | 0.3 - 1.4 | 0.1 - 0.35 | — |
| [STAM500H](/materials/jis/stam500h "STAM500H") | — | max 0.035 | max 0.035 | max 0.3 | 0.3 - 1 | max 0.35 | — |
| [SF440A](/materials/jis/sf440a "SF440A") | — | max 0.03 | max 0.035 | max 0.6 | 0.3 - 1.2 | 0.15 - 0.5 | — |
| [SDR295](/materials/jis/sdr295 "SDR295") | — | max 0.03 | max 0.02 | max 0.27 | max 1.9 | max 0.55 | max 0.01 |
| [SS540](/materials/jis/ss540 "SS540") | — | max 0.04 | max 0.04 | max 0.3 | max 1.6 | — | — |
| [SF540B](/materials/jis/sf540b "SF540B") | — | max 0.03 | max 0.035 | max 0.6 | 0.3 - 1.2 | 0.15 - 0.5 | — |
| [SN400C](/materials/jis/sn400c "SN400C") | — | max 0.02 | max 0.08 | max 0.22 | 0.6 - 1.5 | max 0.35 | — |
| [STKR490](/materials/jis/stkr490 "STKR490") | — | max 0.04 | max 0.04 | max 0.18 | max 1.5 | max 0.55 | — |
| [STW370](/materials/jis/stw370 "STW370") | — | max 0.04 | max 0.04 | max 0.25 | — | — | — |
| [SWH400L](/materials/jis/swh400l "SWH400L") | — | max 0.03 | max 0.015 | max 0.2 | max 1.4 | max 0.35 | — |
| [STKM11A](/materials/jis/stkm11a "STKM11A") | — | max 0.04 | max 0.04 | max 0.12 | max 0.6 | max 0.35 | — |
| [SD345](/materials/jis/sd345 "SD345") | — | max 0.04 | max 0.04 | max 0.27 | max 1.6 | max 0.55 | — |
| [STS410](/materials/jis/sts410 "STS410") | — | max 0.035 | max 0.035 | max 0.3 | 0.3 - 1.4 | 0.1 - 0.35 | — |
| [STKM12C](/materials/jis/stkm12c "STKM12C") | — | max 0.04 | max 0.04 | max 0.2 | max 0.6 | max 0.35 | — |
| [SR240](/materials/ks/sr240 "SR240") | — | max 0.05 | max 0.05 | — | — | — | — |
| [SGDB](/materials/jis/sgdb "SGDB") | — | max 0.045 | max 0.045 | — | — | — | — |
| [STKM14A](/materials/jis/stkm14a "STKM14A") | — | max 0.04 | max 0.04 | max 0.3 | 0.3 - 1 | max 0.35 | — |
| [SD400](/materials/ks/sd400 "SD400") | — | max 0.05 | max 0.05 | — | — | — | — |
| [STK400](/materials/jis/stk400 "STK400") | — | max 0.04 | max 0.04 | max 0.25 | — | — | — |
| [SGD4](/materials/jis/sgd4 "SGD4") | — | max 0.045 | max 0.045 | 0.2 - 0.25 | 0.3 - 0.6 | — | — |
| [STKM15C](/materials/jis/stkm15c "STKM15C") | — | max 0.04 | max 0.04 | 0.25 - 0.35 | 0.3 - 1 | max 0.35 | — |
| [SD600](/materials/ks/sd600 "SD600") | — | — | — | — | — | — | — |
| [SM490YA](/materials/jis/sm490ya "SM490YA") | — | max 0.035 | max 0.035 | max 0.2 | max 1.6 | max 0.55 | — |
| [SR235](/materials/jis/sr235 "SR235") | — | max 0.05 | max 0.05 | — | — | — | — |
| [STKM17C](/materials/jis/stkm17c "STKM17C") | — | max 0.04 | max 0.04 | 0.45 - 0.55 | 0.4 - 1 | max 0.4 | — |
| [SPS400](/materials/ks/sps400 "SPS400") | — | max 0.04 | max 0.04 | max 0.25 | — | — | — |
| [STAM290GA](/materials/jis/stam290ga "STAM290GA") | — | max 0.035 | max 0.035 | max 0.12 | max 0.6 | max 0.35 | — |
| [SFB1](/materials/jis/sfb1 "SFB1") | — | max 0.03 | max 0.035 | 0.05 - 0.2 | 0.3 - 0.9 | 0.15 - 0.5 | — |
| [STKM19A](/materials/jis/stkm19a "STKM19A") | — | max 0.04 | max 0.04 | max 0.25 | max 1.5 | max 0.55 | — |

 Page 1 of 10[Next](/categories/unalloyed-structural-steels/page/2 "Next")

## Standards covering this category

 32

- [**DIN / EN***314 grades*](/materials/din-en "DIN / EN — 314 grades in this category")
- [**JIS***147 grades*](/materials/jis "JIS — 147 grades in this category")
- [**KS***92 grades*](/materials/ks "KS — 92 grades in this category")
- [**BS***60 grades*](/materials/bs "BS — 60 grades in this category")
- [**ČSN***56 grades*](/materials/csn "ČSN — 56 grades in this category")
- [**AISI / SAE***53 grades*](/materials/aisi-sae "AISI / SAE — 53 grades in this category")
- [**AFNOR***52 grades*](/materials/afnor "AFNOR — 52 grades in this category")
- [**UNS***48 grades*](/materials/uns "UNS — 48 grades in this category")
- [**GOST***40 grades*](/materials/gost "GOST — 40 grades in this category")
- [**UNI***38 grades*](/materials/uni "UNI — 38 grades in this category")
- [**GB***36 grades*](/materials/gb "GB — 36 grades in this category")
- [**UNE***33 grades*](/materials/une "UNE — 33 grades in this category")
- [**PN***32 grades*](/materials/pn "PN — 32 grades in this category")
- [**SS***28 grades*](/materials/ss "SS — 28 grades in this category")
- [**ASTM***27 grades*](/materials/astm "ASTM — 27 grades in this category")
- [**STN***27 grades*](/materials/stn "STN — 27 grades in this category")
- [**ÖNORM***26 grades*](/materials/onorm "ÖNORM — 26 grades in this category")
- [**NBN***26 grades*](/materials/nbn "NBN — 26 grades in this category")
- [**MSZ***24 grades*](/materials/msz "MSZ — 24 grades in this category")
- [**ISO***23 grades*](/materials/iso "ISO — 23 grades in this category")
- [**BDS***18 grades*](/materials/bds "BDS — 18 grades in this category")
- [**STAS***17 grades*](/materials/stas "STAS — 17 grades in this category")
- [**SRPS***13 grades*](/materials/srps "SRPS — 13 grades in this category")
- [**SANS***10 grades*](/materials/sans "SANS — 10 grades in this category")
- [**SFS***10 grades*](/materials/sfs "SFS — 10 grades in this category")
- [**NP***7 grades*](/materials/np "NP — 7 grades in this category")
- [**ABNT NBR***7 grades*](/materials/abnt "ABNT NBR — 7 grades in this category")
- [**AS / NZS***7 grades*](/materials/as-nzs "AS / NZS — 7 grades in this category")
- [**NS***5 grades*](/materials/ns "NS — 5 grades in this category")
- [**SNV***4 grades*](/materials/snv "SNV — 4 grades in this category")
- [**CSA***3 grades*](/materials/csa "CSA — 3 grades in this category")
- [**HRN***2 grades*](/materials/hrn "HRN — 2 grades in this category")

## Property ranges

 21

| Property | Unit | Min | Max | Grades |
|---|---|---|---|---|
| ReH | N/mm² | 120 | 550 | 45 |
| Rm | N/mm² | 255 | 1050 | 182 |
| A80 | % | 4 | 32 | 17 |
| Re | N/mm² | 165 | 700 | 145 |
| A | % | 5 | 41 | 151 |
| A5 | % | 7 | 36 | 29 |
| Z | % | 18 | 68 | 23 |
| aK | J/cm² | 29 | 98 | 4 |
| KCU | kJ/m² | 240 | 780 | 6 |
| HB | — | 90 | 255 | 28 |
| HV | — | 100 | 105 | 3 |
| rho | g/cm³ | 7.582 | 7.871 | 319 |
| E | GPa | 141 | 213 | 7 |
| alpha | 10^-6/K | 11 | 15.6 | 6 |
| lambda | W/(m·K) | 27 | 76 | 6 |
| cp | J/(kg·K) | 466 | 875 | 6 |
| rho\_el | nΩ·m | 140 | 1135 | 5 |
| Ac1 | °C | 720 | 745 | 13 |
| Ac3 | °C | 770 | 880 | 13 |
| Ar3 | °C | 755 | 854 | 12 |
| Ar1 | °C | 677 | 700 | 13 |

Derived from 319 grades in this category with a recorded value.

## Composition range

 15

| Property | Unit | Min | Max | Grades |
|---|---|---|---|---|
| B | % | 0.0008 | 0.005 | 1 |
| C | % | 0.004 | 0.6 | 318 |
| N | % | 0.0012 | 0.1 | 85 |
| Al | % | 0.01 | 0.06 | 38 |
| Si | % | 0.03 | 4.5 | 217 |
| P | % | 0.01 | 0.12 | 336 |
| S | % | 0.015 | 0.08 | 336 |
| Ti | % | 0.03 | 0.3 | 26 |
| V | % | 0.02 | 0.2 | 11 |
| Cr | % | 0.12 | 0.5 | 18 |
| Mn | % | 0.03 | 1.9 | 283 |
| Ni | % | 0.12 | 0.3 | 17 |
| Cu | % | 0.03 | 0.55 | 42 |
| Nb | % | 0.01 | 0.08 | 12 |
| Mo | % | 0.05 | 0.35 | 14 |

Derived from 336 grades in this category with a recorded value.

## Heat treatment

 3

| Operation | Min Temperature (°C) | Max Temperature (°C) | Grades |
|---|---|---|---|
| normalizing | — | — | 4 |
| annealing | — | — | 3 |
| tempering | — | — | 1 |