ASTM A193 B8 A320 B8 W 1.4307 AISI 304L

The ASTM specification A193 grade B8 or A320 grade B8 defines the technical characteristics of stainless steel hardware suitable for application in pressure vessels and in the presence of high or low temperature (service temperatures -196°C to 800°C); this type of hardware is widely used in the chemical plants oil and energy sectors. ASME SA 193 B8 SA 320 B8 specifications echo the technical specifications of ASTM A193 B8 A320 B8. This material is suitable for making components that reflect EN ISO® 3506-1 and EN ISO® 3506-2 standards in the different mechanical strength characteristics depending on the state of the finished part (A2-50 A2-70 A2-80).

CHEMICAL COMPOSITION ASTM A193 B8 A320 B8 W 1.4307 AISI 304L

---

Element	Content
C max	0.08
S max	0.03
P max	0.045
Yes max	1.0
Mn max	2.0
Cr	18.0-22.0
Ni	8.0-11.0

MECHANICAL CHARACTERISTICS ASTM A193 B8 A320 B8 W 1.4307 AISI 304L

---

Material	League	Rm min (MPa)	Rp 0.2 min (MPa)	A% min	Z% min	Hardness max (HB)
ASTM A193 B8 Class 1	1.4307	515	205	30	50	223
ASTM A193 B8 Class 2 ≤ 20 mm	1.4307	860	690	12	35	321
ASTM A193 B8 Class 2 > 20 mm < 24 mm	1.4307	795	550	12	35	321
ASTM A193 B8 Class 2 > 24 mm < 30 mm	1.4307	725	450	20	35	321
ASTM A193 B8 Class 2 > 30 mm < 36 mm	1.4307	690	345	28	45	321

PHYSICAL PROPERTIES ASTM A193 B8 A320 B8 W 1.4307 AISI 304L

---

• Specific gravity: 7 kg/dm³ 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
• Amagnetic: Yes

CORRESPONDENCE AND SPECIFICATIONS ASTM A193 B8 A320 B8 W 1.4307 AISI 304L

---

• EN 10088/3: X2 Cr Ni 1811 X2 Cr Ni 1811
• W: 1.4307 – 1.4306
• JIS: G4303 – SUS304
• AISI: 304 L
• EN 3506-1/2: A2-50 A2-70 A2-80