Effect of depth of cut on metal removal rate (MRR) In turning or similar machining operations, how does the material removal rate change when the depth of cut is increased (with all other parameters held constant)?

Introduction / Context:
Material removal rate (MRR) is a primary productivity measure in machining. Knowing how speed, feed, and depth of cut affect MRR lets a process engineer balance cycle time against power, tool wear, and surface integrity.

Given Data / Assumptions:

• Turning operation on a lathe (similar logic holds for many processes).
• Feed and cutting speed held constant; depth of cut is varied.
• Stable cutting without chatter or tool overload.

Concept / Approach:
For turning, a common expression is MRR = cutting speed * feed per revolution * depth of cut * constant (accounting for units and geometry). With speed and feed fixed, increasing depth of cut increases the uncut chip cross-sectional area linearly, therefore increasing MRR linearly—up to machine power and rigidity limits.

Step-by-Step Solution:

Verification / Alternative check:
Power consumption and cutting force rise with depth of cut; this correlates with higher MRR. Machine power charts show permissible depth increases until reaching spindle/drive limits.

Why Other Options Are Wrong:
Decreased/Unchanged: contradicts the geometric definition of MRR.Zero after a limit: not physically meaningful in normal ranges.Non-linear/unpredictable: under steady conditions the relation is straightforward.

Common Pitfalls:
Pushing depth too far can cause chatter, poor finish, or tool breakage; productivity gains must be balanced with tool life and machine rigidity.

Final Answer:

Increased