In SAE-AISI designation, boron in steel is indicated by which pattern?

In SAE-AISI designation, boron in steel is indicated by which pattern?

• A. xxBxx
• B. Bx
• C. B
• D. Boron is not indicated

Answer: (A)

In SAE-AISI designations, boron is shown by inserting the letter B in the middle of the four-digit grade. This creates the pattern two digits, B, two digits (xxBxx). The B marks boron as an alloying addition to that grade, while the digits around it reflect the base composition and other alloying details. This convention distinguishes boron-containing steels from plain carbon steels or other alloys that don’t use this middle-letter pattern. Other formats don’t follow the standard SAE-AISI encoding, so they aren’t used to indicate boron.

In SAE-AISI designations, boron is shown by inserting the letter B in the middle of the four-digit grade. This creates the pattern two digits, B, two digits (xxBxx). The B marks boron as an alloying addition to that grade, while the digits around it reflect the base composition and other alloying details. This convention distinguishes boron-containing steels from plain carbon steels or other alloys that don’t use this middle-letter pattern. Other formats don’t follow the standard SAE-AISI encoding, so they aren’t used to indicate boron.