Topic: Manufacturing Engineering
Knife line or hairline cracking is observed in
- A. Ferritic stainless steel
- B. Martensitic stainless steel
- C. Austenitic stainless steel
- D. Stabilized stainless steel
Answer: D. Stabilized stainless steel
Explanation: Knife line (or) hairline cracking is typically observed in stabilized austenitic stainless steels (like those stabilized with Ti or Nb) due to intergranular corrosion in a very narrow band immediately adjacent to the weld fusion line.