60-40-18 ductile iron is equal to 400-12, but with higher elongation. 60-40-18 is US standard ASTM A536, while 400-12 is Australia standard AS 1831. In the meantime, the equal grade in China is QT400-18 or QT400-15.
Properties of 60-40-18 ductile iron/400-12 cast iron
60-40-18 ductile iron is the lowest grade of ductile iron. Its minimum tensile strength is 414 Mpa (60.000 psi); the minimum yield strength is 276 Mpa (40.000 psi); the minimum elongation is 18%. For 400-12 in the Australian standard AS 1831, the minimum value of elongation is 12%.
Elongation means that the test bar could be pulled and lengthened at least by 18%. In this regard, this material grade has the best elongation properties. This means it has the best ductility. Moreover, it has the best long-term temperature shock performance. Due to its good performance, this material grade has been widely used.
Hardness of 60-40-18 ductile iron/400-12 cast iron
The hardness of this ductile cast iron grade is between 49-187 Brinell hardness. However, we usually will not take hardness into inspection standard, unless the clients have special requirements.
Higher hardness may cause the difficulty and low speed of machining, while lower hardness means that it couldn’t reach the grade. Thus, normally, foundries should produce this grade of ductile iron castings within this range.
Chemistry composition of 60-40-18 ductile iron/400-12 cast iron
According to the standard ASTM A536 and AS 1831, the foundries could adjust the chemical composition as long as the mechanical and physical properties of the castings could meet the requirements in Standards.
The following chart is an approximate chemical composition range for your reference.
|ASTM||ISO||C %||Si %||Mn %||P %||S %||Mg %|
Density of 60-40-18 ductile iron/400-12 cast iron
The density of this ductile iron grade is about 7.3 g/cm3.
Foundry of 60-40-18 ductile iron castings
These ductile iron castings were produces by Yide Casting in China.