What is extrusion?
A
Cutting metal using high-speed tools
B
Forcing metal through a die to create a specific cross-section
C
Welding two metal pieces together
D
Pouring molten metal into a mold
Analysis & Theory
Extrusion is the process of forcing material through a die to form objects of a fixed cross-sectional profile.
Which of the following is a common type of extrusion?
Analysis & Theory
Backward (or indirect) extrusion is where the billet and die move in the same direction.
What is the primary benefit of cold extrusion?
A
Better surface finish and strength
B
Higher temperature tolerance
C
Easier handling of molten metals
Analysis & Theory
Cold extrusion produces parts with excellent surface finish and high strength due to strain hardening.
Which is NOT a type of sheet metal forming?
Analysis & Theory
Casting is not a sheet metal forming process; it is a metal shaping process involving molten metal.
What defect occurs when the metal cracks along the edges during extrusion?
Analysis & Theory
Surface cracking occurs when metal cools and cracks along the surface during extrusion.
Which defect is common in deep drawing sheet metal operations?
Analysis & Theory
Wrinkling happens when excess metal folds due to compressive forces during deep drawing.
Which operation involves removing a piece from sheet metal?
Analysis & Theory
Blanking removes a portion of the sheet which becomes the workpiece.
What is 'springback' in sheet metal forming?
C
Elastic recovery causing shape distortion
D
Sheet tearing during bending
Analysis & Theory
Springback is the tendency of metal to return slightly to its original shape after bending due to elasticity.
Which material is commonly used in extrusion processes?
Analysis & Theory
Aluminum is widely used in extrusion due to its ductility and ease of shaping.
What is 'center burst' in extrusion?
C
Internal rupture along the axis
Analysis & Theory
Center burst is an internal defect in extrusion caused by excessive deformation or improper die design.