Q1: For hardening high alloy steel, it is to be heated slowly and uniformly to avoid

ANS:D - warpage

For hardening high alloy steel, it is essential to heat it slowly and uniformly to avoid local hardening. Explanation:

• Local Hardening: If the high alloy steel is heated too quickly or non-uniformly, it can lead to localized overheating and rapid cooling, resulting in uneven hardness across the material. This localized hardening can lead to undesirable mechanical properties and may cause issues during subsequent processing or use.
• Scale Formation: Heating high alloy steel too quickly can also lead to excessive oxidation and scale formation on the surface of the material. Scale formation can negatively affect the surface quality and may require additional cleaning or machining processes to remove, increasing manufacturing costs and time.
• Segregation: Uniform heating helps to minimize chemical segregation within the steel, ensuring consistent properties throughout the material. Segregation of alloying elements can lead to variations in hardness, toughness, and other mechanical properties, which may compromise the performance of the steel in service.
• Warpage: Rapid or uneven heating can induce thermal stresses in the material, leading to warpage or distortion of the steel components. Slow and uniform heating helps to minimize thermal gradients and reduce the likelihood of warpage during the hardening process.