Question

The molten metal is forced into mould under high pressure in a 0.4pt casting method.

• A. die
• B. slush
• C. centrifugal
• D. permanent mould

Hint:

Associate keywords with casting processes:

• High Pressure \(\rightarrow\) Die Casting

• Rotation \(\rightarrow\) Centrifugal Casting

• Gravity + Metal Mold \(\rightarrow\) Permanent Mould Casting

• Expendable Pattern \(\rightarrow\) Investment Casting

Answer 1

The Correct Option is A

Step 1: Understanding the Concept:
Casting processes can be broadly classified based on the type of mold used (expendable or permanent) and the method of filling the mold (gravity or pressure). The question describes a process that uses high pressure to fill the mold.

Step 2: Detailed Explanation:
Let's examine the casting methods listed:

• (A) Die casting: This process is defined by the use of high pressure to inject molten metal into a reusable metal mold, known as a die. The high pressure ensures that the metal rapidly fills all the intricate details of the die and results in a fine-grained structure and good surface finish.

• (B) Slush casting: This is a process for making hollow castings without a core. Metal is poured into a mold, allowed to form a thin solid shell on the inside, and then the remaining liquid metal is poured out. It does not use high pressure.

• (C) Centrifugal casting: This process uses centrifugal force, generated by a rotating mold, to distribute the metal. It is not an external pressure injection method.

• (D) Permanent mould casting: This process uses a reusable metal mold, but the molten metal is typically poured into the mold under gravity. It is also known as gravity die casting. It does not involve forcing the metal under high external pressure.
The key phrase "forced into mould under high pressure" is the defining characteristic of die casting.

Step 3: Final Answer:
Die casting is the method where molten metal is forced into a mold cavity under high pressure.