ASTM A193 Grade B8NA Specification for high tensile bolts, screws, stud bolts, anchor bolts, threaded rods and other externally threaded fasteners, made from 304N stainless steel.

ASTM A193 Grade B8NA is a standard material specification for high strength 304N stainless steel fasteners such as bolts, screws, studs, threaded rods and other externally threaded parts, for use in high tensile, high temperature and special purpose applications such as pressure piping & pressure vessels bolting. Grade B8NA is similar to Grade B8N except that the latter is carbide solution treaded after head forming and the former is carbide solution treated in finished condition. Grade B8NA is classified under class 1A having minimum tensile requirement of 75 ksi, yield 30 ksi and maximum hardness limit of 192 HBW or 90 HRB. This specification covers requirements for chemical composition, mechanical properties, hardness, heat-treatment and recommended nuts-washers for Grade B8NA Fasteners.

Chemical Composition

Element	Austenitic Stainless Steel
	AISI 304N / UNS S30451
	CompositionA, %
Carbon	0.08 max
Manganese	2.00
Phosphorus	0.045 max
Sulfur	0.030 max
Silicon	1.00 max
Chromium	18.00 - 20.00
Nickel	8.00 - 11.00
Molybdenum	0.10 - 0.16

^AThe intentional addition of Bi, Se, Te, and Pb is not permitted.

Mechanical Properties

Tensile Class	Diameter, Inch	Tensile Strength, min, ksi	Yield Strength, min, 0.2% offset, ksi	Elongation in 4D, min, %	Reduction of Area, min, %	Hardness, max
								Class 1A	All Sizes	70	30	30	50	192 HBW or 90 HRB

Heat Treatment: Carbide Solution Treated in finished condition.