bolts

Fasteners made from this austenitic stainless steel require carbide solution treatment of the bar to be threaded, or carbide solution treatment after the head operation of bolts with forged heads.

Carbide solution treatment, also known as solution annealing, is a process in which fasteners or stainless steel rods are heated and then water quenched to ensure maximum corrosion resistance. A193 Grade B8 Grade 2 bolts are strain hardened after carbide solution treatment to improve strength properties and reduce the potential for wear.

The ASTM A194 specification covers a wide variety of carbon, alloy, and martensitic stainless steel nuts in sizes ranging from 1/4 to 4 inches and metric M6 to M100 nominal. It also covers austenitic stainless steel nuts in the size range of 1/4 inch and M6 nominal and above. These nuts are used for high pressure or high temperature service, or both.

ASTM A193 Grade B8M Grade 1 Fasteners are similar to Grade B8 but are made of AISI 316 stainless steel instead of AISI 304 stainless steel. Type 316 stainless steel has better corrosion resistance than type 304 stainless steel due to the addition of molybdenum.

B8M Grade 1 fasteners require carbide solution treatment, while Grade 2 fasteners require additional strain hardening operations to increase strength and reduce susceptibility to wear.