SG Iron is known as Spheroidal Graphite Iron, and also known as Ductile Cast Iron, Nodular Cast Iron, or Spherulitic Graphite Cast Iron.
SG Iron is a type of cast iron that has been treated while molten with an element such as magnesium or cerium to induce the formation of free graphite as nodules or spherulites.
The followings are the grade requirement to the chemical components and physical properties, and also grade comparison chart. At the same time, we listed the main content of material standards using in USA, China, Germany, Europe and International.
Please notice that the chemical components are only a reference, not a strict standard to the material. The foundry could adjust its chemical components according to their experience in order to meet the physical properties. So, physical properties should be the only standard to materials.
Chemical Components of SG Cast Iron
SPECIFICATION FOR CAST (GREY) IRON
| Country | Specification | Designation | 150 | 180 | 200 | 220 | 250 | 260 | 300 | 350 |
|---|---|---|---|---|---|---|---|---|---|---|
| India | IS 210 1978 | FG | 150 | -- | 200 | -- | 250 | -- | 300 | 350 |
| United Kingdom | BS 1452 1990 | Grade | 150 | 180 | 200 | 220 | 250 | -- | 300 | 350 |
| USA | ANS/ASTM A48-83 | Grade | 20A | 25A | 30A | -- | 35A | 40A | 45A | 50A |
| Germany | DIN 1691 1985 | GG | 15 | -- | 20 | -- | 25 | -- | 30 | 35 |
| France | NFA 32-101-1987 | FGL | 150 | -- | 200 | -- | 250 | -- | 300 | 350 |
| Italy | UNI 5007 1969 | G | 15 | -- | 20 | -- | 25 | -- | 30 | 35 |
| Japan | JIS G5501 1981 | FC | 150 | -- | 200 | -- | 250 | -- | 300 | 250 |
| Russia | GOST 1412 1979 | Sch | 15 | 18 | 20 | -- | 25 | -- | 30 | 35 |
| International | ISO 185-1988 | Grade | 150 | -- | 200 | -- | 250 | -- | 300 | 350 |
| CLASS | 2 | -- | 3 | -- | 4 | -- | 5 | 6 | ||
| Hardness Range BHN | 136-167 | 159-194 | 180-222 | 202-247 | 227-278 | |||||
| Total Carbon % | 3.4-3.6 | 3.2-3.5 | 3.15-3.30 | 2.9-3.1 | 3.1 max | |||||
| Silicon % | 2.2-2.5 | 2.0-2.5 | 1.6-1.9 | 1.8-2.0 | 1.4-1.6 | |||||
| Mangenese % | 0.5-0.7 | 0.6-0.8 | 0.6-0.8 | 0.7-0.9 | 0.7-0.9 | |||||
| Sulphur % | 0.15 | 0.15 | 0.12 max | 0.10 max | 0.10 max | |||||
| Phosphorous % | 0.9-1.2 | 0.4 max | 0.3 max | 0.10 max | 0.10 max | |||||
| Molybdenum % | 0.3-0.5 | |||||||||
| Cu or Ni % | 0.3-0.5 | 1.0-1.5 | ||||||||
NOTE: The above standards for ordering reference only the customer can specify any special requirement. All specifications are subject to change without prior notice.
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SPECIFICATION FOR DUCTILE (NODULAR / SPHEROIDAL IRON)
| Country | Specification | Designation | Minimum Tensile Strength / Elongation | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| India | SG | 800/2 | 700/2 | 600/3 | 500/7 | 420/12 | 400/18 | 350/22 | ||||||
| United Kingdom | BS2789:1985 | 800/2 | 700/2 | 600/3 | 500/7 | 420/12 | 400/18 | 350/22 | ||||||
| USA | ASTM A536-84:1976 | 120-90-02 | 100-70-03 | 80-60-03 | 80-55-06 | 65-45-12 | 60-42-10 | 60-40-18 | ||||||
| German | Din 1693-1973 | GGG | 800/2 | 700/2 | 600/3 | 500/7 | 400/15 | 400/18 | 350/22 | |||||
| France | NF A 32-201:1976 | FGS | 800/2 | 700/2 | 600/3 | 500/7 | 400/12 | 370/17 | -- | |||||
| Italy | UNI 4544:1979 | GS | 800/2 | 700/2 | 600/3 | 500/7 | 400/12 | 370/17 | -- | |||||
| Japan | JIS G5502:1982 | FCD | (80)758/2 | (70)686/2 | (60)588/3 | (50)490/7 | (40)392/12 | (37)363/17 | -- | |||||
| International | ISO 1083:1976 | 800/2 | 700/2 | 600/3 | 500/7 | 400/12 | 370/17 | |||||||
| (827/2) | (689/3) | (555/3) | (552/6) | (448/12) | (415/10) | (414/18) | ||||||||
| Hardness BHN | 248-352 | 229-302 | 192-269 | 170-241 | 201 max | 179 max | 160 max | |||||||
| Structure | P or T | P | P & F | F & P | F | F | F | |||||||
| Equivalence kgf/mm2 | 81.6 | 71.4 | 61.2 | 51 | 42.8 | 40.8 | 35.7 | |||||||
| TC | Si | Mn (max) | TC | Si | Mn (max) |
TC | Si | Mn (max) |
Tc | Si | Mn (max) |
|||
| 3.6-3.8 | 2.6-2.8 | 0.5 | 3.6-3.8 | 2.6-2.8 | 0.3 | 3.6-3.8 | 2.6-2.8 | 0.2 | 3.6-3.8 | 2.6-2.8 | 0.1 | |||
| 3.5-3.6 | 2.2-2.5 | 0.6 | 3.5-3.6 | 2.2-2.5 | 0.35 | 3.5-3.6 | 2.2-2.4 | 0.25 | 3.5-3.6 | 2.2-2.4 | 0.15 | |||
| 3.5-3.6 | 2.1-2.3 | 0.7 | 3.5-3.6 | 2.1-2.4 | 0.4 | 3.5-3.6 | 2.1-2.4 | 0.3 | 3.5-3.6 | 2.2-2.4 | ||||
| 3.4-3.5 | 1.9-2.1 | 0.8 | 3.4-3.5 | 2.0-2.2 | 0.5 | 3.4-3.5 | 2.0-2.2 | 0.35 | 3.4-3.5 | 1.8-2.0 | ||||
| 3.4-3.5 | 1.8-2.0 | 0.8 | 3.4-3.5 | 1.8-2.0 | 0.6 | 3.4-3.5 | 1.8-2.0 | 3.4-3.5 | 1.8-2.0 | 0.25 | ||||
NOTE: The above standards for ordering reference only the customer can specify any special requirement. All specifications are subject to change without prior notice.