The strength of the spheroidal graphite(SG) or nodular cast  iron is a result of a change in morphoglgy of flake graphite into  graphite spheroids. The lower surface area to volume of the spheroids increases its fracture toughness and hence reduces  crack propagation. SG iron is an excellent conductor of heat  and increases the resistance to fire-cracks by reducing the  locally induced thermal stresser. The impact resistance is also  increased to that of flake graphite iron.


This grade, Alloyed with the Nickel, Manganese and Chromium with a Bainitic-Acicular-Martensitic Matrix has a higher UTS, hardness and is more wear resistant than the SGP quality. Semi-continuous carbides maintain the wear resitance, while at the same time exhibiting high strength and resistance to fire-cracks. The extensive heat treatment procedure ensures an acicular matrix.  This grade can be produced by Static Casting (Monoblock) or by using the Centrifugal Cast (CC) Double-pour method.

Chemical Analysis

sga chemical