Chip formation fundamentals: High cutting speed and a large rake angle generally promote which chip type in ductile materials?

Introduction / Context:
Chip type affects tool wear, surface finish, and process stability. Tool geometry and cutting parameters steer whether the chip is continuous, segmented, or discontinuous. The question focuses on the effect of high cutting speed and large rake angle.

Given Data / Assumptions:

• Ductile work metal (e.g., low-carbon steel, aluminum).
• Sharp tool with a relatively large positive rake angle.
• Sufficient cutting speed to suppress built-up edge formation.

Concept / Approach:
Large rake reduces shear deformation and cutting forces, while higher speed raises temperature at the shear plane, both encouraging smooth chip flow. These conditions usually suppress built-up edge and promote long, continuous chips in ductile materials.

Step-by-Step Solution:

Verification / Alternative check:
Visual observation and chip morphology under these settings typically show ribbon-like continuous chips with good surface finishes.

Why Other Options Are Wrong:

• Discontinuous chips arise with brittle materials, low rake, or interrupted/low-speed cutting.
• Continuous with built-up edge is more likely at moderate/low speeds or poor lubrication.
• “None of these” conflicts with standard metal cutting behavior.

Common Pitfalls:
Assuming continuous chips are always desirable; they can entangle tools—chip breakers or peck cycles may still be needed.

Final Answer:
Continuous chips