Negative rake angle application Negative rake angles are most commonly provided on which class of cutting tools due to their hot hardness and edge strength requirements?

Introduction / Context:
Tool rake angle affects cutting forces, temperature, edge strength, and tool life. Negative rake is often used to strengthen the cutting edge and withstand high cutting speeds that produce elevated temperatures.

Given Data / Assumptions:

• Comparing typical rake choices for tool materials.
• Operations at moderate to high cutting speeds.
• Need for edge strength and hot hardness.

Concept / Approach:
Cemented carbide has excellent hot hardness and compressive strength. Negative rake reduces the wedge angle thinning, making the edge stronger under heavy loads and intermittent cuts. HSS and carbon steel tools typically use positive rake to lower forces, because their hot hardness is lower than carbides.

Step-by-Step Solution:
Identify the tool requiring high edge strength at high speeds: cemented carbide.Relate negative rake to improved wedge strength and crater wear resistance.Select the option that matches common industrial practice.

Verification / Alternative check:
Carbide insert catalogs list many neutral/negative rake geometries for steel machining and roughing, confirming widespread use.

Why Other Options Are Wrong:
High carbon steel and HSS normally rely on positive rake to control forces and heat; they lack the hot hardness for sustained negative-rake, high-speed work.

Common Pitfalls:
Assuming negative rake always improves life; in finishing cuts on ductile materials, positive rake may still be preferable for lower forces and better finish.

Final Answer:
Cemented carbide tools