ASTM A193 Grade B8TA Specification

ASTM A193 Grade B8TA Specification for high tensile bolts, screws, stud bolts, anchor bolts, threaded rods and other externally threaded fasteners, made from 321 stainless steel.

ASTM A193 Grade B8TA is a standard material specification for corrosion resistant 321 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 B8TA is a carbide solution treated 321 stainless steel and similar to B8T except that the latter is carbide solution treated after head forming and the former is carbide solution treated in finished condition. Grade B8TA is classified under tensile class 1A haveing 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 B8TA Fasteners.

Chemical Composition

Element Austenitic Stainless Steel
AISI 321 / 321H
CompositionA, %
Carbon 0.08 max
Manganese 2.00
Phosphorus 0.045 max
Sulfur 0.030 max
Silicon 1.00 max
Chromium 17.00 - 19.00
Nickel 9.00 - 12.00
Titanium 5 x Carbon Content - 0.70
Nitrogen 0.10 max

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 1 All Sizes 75 30 30 50 192 HBW or 90 HRB

Heat Treatment: Carbide Solution Treated in finished condition.