Mechanical Engineering - Engineering Materials - Discussion

The correct answer is Cast iron.

Cast iron exhibits the largest shrinkage from the molten state to the solid state, typically around 4-5%. This is due to its high carbon content, which causes a significant volume contraction during solidification.

Here's a brief comparison of the shrinkage of the other options:

- Cast steel: Typically shrinks around 2 - 3% from the molten state to the solid state.
- Brass: Typically shrinks around 1.5 - 2.5% from the molten state to the solid state.
- Admiralty metal (a type of gunmetal): Typically shrinks around 1.5 - 2% from the molten state to the solid state.

The high shrinkage of cast iron can lead to casting defects, such as porosity, shrinkage cavities, and cracking. To minimize these issues, foundries often use techniques like risering, padding, and feeding to compensate for the shrinkage.

So, the exact shrinkage values can vary depending on the specific alloy composition, solidification conditions, and casting process.

The right answer is cast steel.

It is an alloy of copper, tin and zinc. It is widely used in casting boiler fittings, bearings, bushes etc.

Admiralty metal: An alloy of not less than 70 percent copper, about 1 percent tin, small amounts of other elements, and the balance zinc, tin brass.

What is Admirality metal?