ASTM A193 Grade B5 Specification

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 1100ยบ F minimum.

Recommended Nuts & Washers

Nut Specification Washer Specification
ASTM A194 Grade 3 ASTM F436

Fasteners

Commonly Produced B5 Fasteners
Hex Bolts Heavy Hex Bolts Stud Bolts Threaded Rods Anchor Bolts
Eye Bolts Socket Head Cap Screws Countersunk Screws U Bolts Square Head Bolts