Question

Match the type of defects in Column I with the corresponding metal manufacturing processes listed in Column II.

Column I	Column II
(P) Edge Cracking	(1) Casting
(Q) Flashline Cracking	(2) Forging
(R) Chevron Cracking	(3) Rolling
(S) Cracked Core	(4) Extrusion

• A. P-3, Q-4, R-2, S-1
• B. P-4, Q-3, R-1, S-2
• C. P-4, Q-2, R-3, S-1
• D. P-3, Q-2, R-4, S-1

Hint:

Recall which manufacturing process each named defect is most commonly seen in.

Answer 1

The Correct Option is D

Step 1: Recall where each defect typically forms.
Each defect in Column I is characteristic of one particular metal working or casting process because of the specific stress state and material flow pattern in that process.

Step 2: Match P (Edge Cracking).
Edge cracking appears along the edges of a rolled sheet or strip when the edges see secondary tensile stresses during rolling, often from uneven deformation across the width of the strip. This defect is specific to rolling, so P matches entry (3), Rolling.

Step 3: Match Q (Flashline Cracking).
Flashline cracking occurs along the flash line of a forged part, where excess metal is squeezed out at the die parting line during closed-die forging. This is a forging-specific defect, so Q matches entry (2), Forging.

Step 4: Match R (Chevron Cracking).
Chevron cracking, also called center-burst cracking, is an internal defect that forms along the centerline of a bar or rod during extrusion, caused by secondary tensile stresses on the centerline when the die angle is large and the reduction per pass is small. So R matches entry (4), Extrusion.

Step 5: Match S (Cracked Core).
Cracked core is a casting defect where the sand or metal core used to form an internal cavity breaks, usually from poor core strength, incorrect venting or thermal stress during pouring and solidification. So S matches entry (1), Casting.

Step 6: Combine and check against the options.
The complete match is P-3, Q-2, R-4, S-1, which is exactly option (D).
\[ \boxed{P\text{-}3,\ Q\text{-}2,\ R\text{-}4,\ S\text{-}1} \]