ASTM A193 Grade B5 Specification for high tensile bolts, screws, stud bolts, anchor bolts, threaded rods and other externally threaded fasteners, made from 5% chromium-ferritic steel.

ASTM A193 Grade B5 is a standard material specification for low alloy chromium-ferritic steel fasteners, for use in high tensile, high temperature and special purpose applications such as pressure piping & pressure vessels bolting. Grade B5 is a heat-treated 5% chromium-ferritic magnetic stainless steel with minimum tensile strength requirement of 100 ksi and yield 80 ksi. ASTM A193 specification covers requirements for chemical composition, mechanical properties, hardness, heat-treatment and recommended nuts-washers for Grade B5 Fasteners.

Chemical Composition

Element	Ferritic Steel
	Chromium-Molybdenum Steel
	CompositionA, %
Carbon	0.10 min
Manganese	1.00
Phosphorus	0.040 max
Sulfur	0.030 max
Silicon	1.00 max
Chromium	1.00 - 6.00
Molybdenum	0.40 - 0.65

A: The intentional addition of Bi, Se, Te, and Pb is not permitted.

Mechanical Properties

Diameter, inch.	Tensile Strength, min, ksi	Yield Strength, min, 0.2% offset, ksi	Elongation in 4D, min, %	Reduction of Area, min, %	Hardness, max
					HBW	HRC
up to 4, inclusive	100	80	16	50	321	35

Heat Treatment: Quenched & Tempered at 1100º F minimum.