Difference Between Grey Cast Iron and White Cast Iron

Like gray cast iron, white cast iron features many small fractures. The difference is that white cast iron features cementite below its surface, whereas gray cast iron features graphite below its surface. The graphite creates the appearance of a gray color, while the cementite creates the appearance of a white color.

1. Is gray iron the same as cast iron?
2. Is GREY cast iron brittle?
3. Is Cast Iron GREY or black?
4. What is white cast iron used for?
5. What are the three types of cast iron?
6. What is the biggest disadvantage of white cast iron?
7. Why GREY cast iron is brittle and weak in tension?
8. What is the reason of low toughness of GREY cast iron?
9. Why is cast iron not weldable?
10. Which cast iron is hardest?
11. What is the effect of nickel on cast iron?
12. What color is raw cast iron?

Is gray iron the same as cast iron?

Gray iron, or grey cast iron, is a type of cast iron that has a graphitic microstructure. It is named after the gray color of the fracture it forms, which is due to the presence of graphite. It is the most common cast iron and the most widely used cast material based on weight.

Is GREY cast iron brittle?

Unfortunately the only commonly known property of gray iron—brittleness—is also assigned to “cast iron” and hence to all cast irons. Gray iron is so named because its fracture has a gray appearance. It contains carbon in the form of flake graphite in a matrix that consists of ferrite, pearlite, or a mixture of the two.

Is Cast Iron GREY or black?

The silicon in grey cast iron causes the carbon to change into graphite. This causes it to have a dark grey or almost black color.

What is white cast iron used for?

White cast irons are used in abrasion-resistant parts where it's brittleness is of minimum concern such as shell liners, slurry pumps, ball mills, lifter bars, extrusion nozzles, cement mixers, pipe fittings, flanges, crushers and pump impellers. A popular grade of white iron is high chrome white irons, ASTM A532.

What are the three types of cast iron?

There are four basic types of cast iron - white iron, gray iron, ductile iron and malleable iron

• white iron.
• gray iron.
• ductile iron.
• malleable iron.

What is the biggest disadvantage of white cast iron?

The biggest disadvantage of white cast iron is not used as extensively as gray cast iron because it is harder, more brittle, and more difficult to machine . It also has less impact strength.

Why GREY cast iron is brittle and weak in tension?

Gray cast iron possess graphitic microstructure. The matrix contains graphite in the shape of flakes. ... So, gray cast iron has low tensile strength. Stress concentration occurs at the tip of these graphite flakes and makes them brittle in nature.

What is the reason of low toughness of GREY cast iron?

What is the reason of low toughness of grey cast iron? Explanation: Grey cast iron has very poor toughness. Its major reason is notch like an effect of graphite flakes. These flakes increase stress concentration in it lowering toughness.

Why is cast iron not weldable?

Cast iron is difficult, but not impossible, to weld. ... Cast iron typically has a carbon content of 2% - 4%, roughly 10 times as much as most steels. The high carbon content causes the carbon to form flakes of graphite. This graphite gives gray cast iron its characteristic appearance when fractured.

Which cast iron is hardest?

While the hardness and strength of steel almost always increase as carbon content rises, in the case of gray cast iron the strongest, hardest grades have less carbon than some of the lower-strength, less expensive grades. Gray iron is usually cast in sand molds, and allowed to cool normally in the mold.

What is the effect of nickel on cast iron?

The increased stability of austenite in cast iron alloyed with nickel makes it possible to control the structure and physicomechanical properties during cooling a~ter solidification or special heat treatment [1, 2].

What color is raw cast iron?

It should look the same as the rest of the pan with no other materials. A raw cast iron pan will have a dull black/dark grey color and be slightly rough to the touch. If the pan still has some seasoning intact it will be a darker black and smooth to the touch.