Chisel Treatment for Steel Sheet Cutting

Chisels used for cutting hard materials like steel sheets must withstand significant impact and abrasion.

To achieve this, the tool needs two primary properties:

• High Hardness: Allows the cutting edge to penetrate and shear the steel without dulling quickly.
• Toughness: Prevents the tool from fracturing or chipping under repeated impacts.

Material Properties Analysis

Let's analyze the given heat treatment options:

• Annealed: Makes the steel soft and ductile, unsuitable for cutting tools.
• Normalized: Refines grain structure, improving toughness slightly but not enough hardness for cutting steel.
• Hardened: Achieves high hardness but makes the steel very brittle, prone to chipping.
• Hardened and Tempered: This process first hardens the steel to achieve the necessary cutting edge hardness. Then, it is tempered (reheated to a lower temperature and cooled) to reduce brittleness, increasing toughness while retaining sufficient hardness.

Therefore, chisels for cutting steel sheets are typically hardened and tempered to provide the required combination of hardness and toughness for effective and durable performance.