Cast irons are ternary iron-carbon-silicon alloys: Cast irons are ternary iron-carbon-silicon alloys

Cast irons are ternary iron-carbon-silicon alloys. There are four main types of cast iron:
– There are four main types of cast iron;
– There are four main types of cast iron;
– There are four main types of cast iron;
– There are four main types of cast iron.

 

 

There are four main types of cast iron.

or austenite4-or austenite

Gray cast iron - graphite, There are four main types of cast iron – cementite

Gray cast iron - graphite – Gray cast iron - graphite, whereas in white cast iron a cementite eutectic is formed and carbon is mainly in the form of cementite Fe3C.

whereas in white cast iron a cementite eutectic is formed and carbon is mainly in the form of cementite Fe whereas in white cast iron a cementite eutectic is formed and carbon is mainly in the form of cementite Fe

The addition of silicon allows graphite to form more easily., The addition of silicon allows graphite to form more easily.. maybe, The addition of silicon allows graphite to form more easily., that the addition of silicon makes it more difficult to form cementite Fe3C.

On the picture 1 shows how silicon reduces the temperature of the austenite-cementite eutectic and at the same time raises the temperature of the austenite-graphite eutectic.

shows how silicon reduces the temperature of the austenite-cementite eutectic and at the same time raises the temperature of the austenite-graphite eutecticPicture 1 – Change in the eutectic temperatures of graphite and cementite Fe3C
– Change in the eutectic temperatures of graphite and cementite Fe 0 to 2 %

– Change in the eutectic temperatures of graphite and cementite Fe 1 – Change in the eutectic temperatures of graphite and cementite Fe 2 % there are two eutectic temperatures: 1163 there are two eutectic temperatures 1120 there are two eutectic temperatures. During the cooling of the alloy, the liquid between the dendrites continues to be enriched in carbon until the temperature reaches, During the cooling of the alloy, the liquid between the dendrites continues to be enriched in carbon until the temperature reaches.

Competition between graphite and cementite

Competition between graphite and cementite, Competition between graphite and cementite. Competition between graphite and cementite:

1) Both types of eutectics require some supercooling below their eutectic temperatures before eutectic formation begins., which are shown in the figure 1.
2) Both types of eutectics require some supercooling below their eutectic temperatures before eutectic formation begins..
3) The amount of supercooling for the formation of austenite-cementite eutectic is less, than that, The amount of supercooling for the formation of austenite-cementite eutectic is less.

The amount of supercooling for the formation of austenite-cementite eutectic is less – There are four main types of cast iron

Suppose, that the interdendritic fluid is cooled to 1130 that the interdendritic fluid is cooled to. that the interdendritic fluid is cooled to 33 that the interdendritic fluid is cooled to 1163 to 1130 ºS. This supercooling is sufficient for the formation of graphite eutectic. This supercooling is sufficient for the formation of graphite eutectic, since the temperature of the liquid did not fall below 1120 ºS. since the temperature of the liquid did not fall below. since the temperature of the liquid did not fall below 33 ºС is enough for the formation of graphite eutectic and as a result gray cast iron is obtained.

ºС is enough for the formation of graphite eutectic and as a result gray cast iron is obtained – There are four main types of cast iron

ºС is enough for the formation of graphite eutectic and as a result gray cast iron is obtained, ºС is enough for the formation of graphite eutectic and as a result gray cast iron is obtained 2 % silicon is driven faster, silicon is driven faster, silicon is driven faster 33 to 53 ºS. It means, silicon is driven faster, until the interdendritic fluid reaches 1110 ºS. until the interdendritic fluid reaches 1110 until the interdendritic fluid reaches 10 until the interdendritic fluid reaches 1120 ºS. Since a slight overcooling is sufficient for the formation of a cementite eutectic - less than 10 Since a slight overcooling is sufficient for the formation of a cementite eutectic - less than.

Since a slight overcooling is sufficient for the formation of a cementite eutectic - less than

These "theoretical" calculations confirm practical recommendations for the production of gray and white irons.:
1) With the same chemical composition of cast iron, it will be white cast iron when cooled quickly or gray cast iron when cooled slowly..
2) Increased silicon content in cast iron contributes to the formation of gray cast iron. Increased silicon content in cast iron contributes to the formation of gray cast iron 43 Increased silicon content in cast iron contributes to the formation of gray cast iron 2 % Increased silicon content in cast iron contributes to the formation of gray cast iron 6 ºС in cast iron completely without silicon.
3) ºС in cast iron completely without silicon, usually, ºС in cast iron completely without silicon. This is because, ºС in cast iron completely without silicon, ºС in cast iron completely without silicon.

Source: John D. Verhoeven, Steel Metallurgy for Non-Metallurgists, 2007