IS 1570 is the master reference for wrought steel designations in India. It is a multi-part standard listing chemical compositions of carbon steels, alloy steels, free cutting steels, and stainless steels. Essential reference for any steel procurement or design specification.
Comprehensive schedule of wrought steel compositions covering carbon steels, alloy steels, and free cutting steels with their chemical composition designations.
Key Values
C45 carbon content0.40-0.50%
C20 carbon content0.17-0.23%
40Cr1 chromium content0.90-1.20%
Practical Notes
! IS 1570 only defines COMPOSITIONS — for mechanical properties, refer to the relevant product standards (IS 2062, IS 1875, etc.).
! The designation system is straightforward: C = carbon steel + number = carbon % x 100. So C45 = 0.45% carbon.
! For alloy steels, the designation includes the alloying element: 40Cr1 = 0.40% C + ~1% Cr.
! EN equivalent designations (e.g., C45 = EN C45) are essentially the same numbering system.