ASTM A193 B8T A320 B8T AISI 321 W. 1.4541

ASTM specification A193 grade B8T A320 grade B8T defines technical specifications for stainless steel fasteners for pressure vessel applications under high temperature (service temperatures 800°C); this type of fastener is widely used in the petroleum and mining and energy chemical plant sectors. ASME SA 193 B8T specifications echo the technical specifications of ASTM A193 B8T A320 B8T.

CHEMICAL COMPOSITION ASTM A193 B8T A320 B8T AISI 321 W. 1.4541

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Element	Content
C max	0.08
S max	0.03
P max	0.045
Yes max	1.0
Mn max	2.0
Cr	17.0-19.0
Ni	9.0-12.0
Ti	5x(C+N) min, 0.70 max
N max	0.10

MECHANICAL CHARACTERISTICS ASTM A193 B8T A320 B8T AISI 321 W. 1.4541

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Material	League	Rm min (MPa)	Rp 0.2 min (MPa)	A% min	Z% min	Hardness max (HB)
ASTM A193 B8T Class 1	1.4541	515	205	30	50	223
ASTM A193 B8T Class 2 ≤ 20 mm	1.4541	860	690	12	35	321
ASTM A193 B8T Class 2 > 20 mm < 24 mm	1.4541	795	550	12	35	321
ASTM A193 B8T Class 2 > 24 mm < 30 mm	1.4541	725	450	20	35	321
ASTM A193 B8T Class 2 > 30 mm < 36 mm	1.4541	690	345	28	45	321

PHYSICAL PROPERTIES ASTM A193 B8T A320 B8T AISI 321 W. 1.4541

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• Bulk density: 7.9 g/cm³ at 20°C
• Modulus of elasticity: 200,000 N/mm² at 20°C
• Thermal conductivity: 14.6 W/m.K at 20°C
• Specific heat: 500 J/g.K at 20°C
• Coefficients of linear expansion: 16.5 (20° – 200°C), 17.5 (20° – 400°C), 18.5 (20° – 600°C)
• Electrical resistivity: 0.73 Ω mm²/m at 20°C
• It is not magnetic.

CORRESPONDENCE AND SPECIFICATIONS ASTM A193 B8T A320 B8T AISI 321 W. 1.4541

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• EN 10088/3: X6 Cr Ni Ti 18 10
• W: 1.4541
• JIS: G4303 – SUS321
• AISI: 321
• ISO 3506-1/2