Blog
ductile iron fittings malaysia

Characteristics of ductile iron: Right Deals

25 Views0 Comment

ductile iron fittings malaysiaThe ductile iron differs from traditional gray cast its outstanding mechanical properties (elasticity, impact strength, elongation). These are due to the spheroidal shape of the graphite particles.

Definition of fonts

A classification of ferrous products can be established based on the carbon content in the base metal:

  • Iron: 0 to 0.1% C,
  • Steel: 0.1 to 1.7% C,
  • Cast iron: 1.7 to 5% C

Below 1.7% carbon, solidification generates austenite, a single-phase material, in the structure of which all the carbon is in solid solution.

Above 1.7% carbon, it cannot be completely dissolved in the iron structure and, therefore, solidifies in the form of a second phase either of graphite (pure C) or of carbide. iron (Fe3C). Cast iron is a multi-phase material with a complex structure: the most common constituents are ferrite (Feα) and perlite (Feα + Fe3C).

Other elements, present in the cast iron in very small proportions, have an influence on the structure and the mechanical and foundry properties of the metal. Silicon (usually 1 to 3%) plays a special role and actually makes cast iron a ternary alloy: iron, carbon, silicon.

Different types of fonts

The term “cast iron” covers a wide variety of Fe – C – Si alloys. It is customary to classify them into families according to the state of the graphite, with an additional differentiation due to the structure of the metal matrix (ferrite, perlite, etc.).

Influence of the shape of graphite

In gray cast irons, the graphite is in the form of lamellae, hence their metallurgical name of lamellar graphite cast irons (or FGL cast iron). Each of these graphite flakes can, under a concentration of abnormal forces at certain points, lead to the initiation of a crack.

Metallurgists have therefore sought to reduce or eliminate these effects by adjusting the size of these lamellae or their arrangement.

Centrifugation has made it possible to obtain very fine lamellae which significantly increase the mechanical qualities of the cast iron.

A decisive step was taken in 1948, when research carried out in the USA and Great Britain made it possible to obtain a spheroidal graphite cast iron (or FGS cast iron), better known as ductile iron .

The graphite is no longer arranged in lamellae, but crystallized in spherical form. The lines of propagation of possible ruptures are thus eliminated.

The crystallization of graphite in the form of spheres is obtained by the controlled introduction of a small quantity of magnesium into a previously desulphurized base iron.

ductile iron fittings malaysia

Characteristics of ductile iron

The ductile iron owes its remarkable mechanical characteristics of spheroidal graphite in it:

  • Tensile strength,
  • Impact resistance,
  • High elastic limit,
  • Significant elongation.

These characteristics can be further improved by mastering the chemical analysis and the heat treatment of the metal matrix.

Ductile iron however retains the traditional mechanical qualities of cast irons, resulting from their high carbon content:

  • Compressive strength,
  • Moldability,
  • Abrasion resistance,
  • Machinability,
  • Fatigue resistance.
  • Normative reference

All ductile iron fittings malaysia, fittings and pipe accessories for water supply are manufactured with a GS cast iron conforming to standard EN 545 and ISO 2531.

ductile iron fittings malaysia