Castings fine grain size

[SSavage]

Please advise the ASTM grain size to achieve "fine grain size" for castings in carbon steel, low alloy steel after normalisation + temper and quench + temper.

 

[stanweld]

Fine grain size has traditionally been defined as ASTM 5 or finer.

 

[arunmrao]

I agree with stanweld regarding the fineness number. You can achieve this by adding grain refiners along with Aluminium which is commonly used as deoxidant. CaSi, Misch metal FeSiZr are the commonly used grain refiners.