Alloy 20 CB 3 Specification

Alloy 20 CB 3 is an austenitic stainless steel with excellent resistance to hot sulphuric acid and many other aggressive environments that would readily attack stainless steel 316. This alloy exhibits superior resistance to stress-corrosion cracking in boiling 20 to 40% sulphuric acid.

Good Mechanical Properties at Elevated Temperatures	No
Corrosion Resistant at Ambient Temperatures	Yes
Corrosion Resistant & Good Mechanical Properties at Elevated Temperatures	No
Oxidation Resistant	No
Precipitation Hardenable	No

Approximate Chemical Composition
Ni	32 - 38%
Cr	19 - 21%
Cu	3 - 4%
Mo	2 - 3%
C	0.07% max
Fe	BAL

Properties
DENSITY	8.08 g/cm3	0.292 lb/in3
MELTING POINT	1425 oC	2600 oF
COEFFICIENT OF EXPANSION	14.69 µm/m °C (20 - 100°C)	8.16 x 10-6 in/in °F (70 - 212°F)
MODULUS OF RIGIDITY	73.6 kN/mm2	10675 ksi
MODULUS OF ELASTICITY	193 kN/mm2	27993 ksi

CONDITION OF SUPPLY	HEAT TREATMENT (AFTER FORMING)
Annealed / Spring Temper	Stress relieve at 250 - 530ºC (480 - 990ºF) for 1 hour and air cool.

CONDITION	APPROX TENSILE STRENGTH		APPROX SERVICE TEMPERATURE
Annealed	600 - 900 N/mm2	87 - 131 ksi	-200 to +300 oC	-330 to +570 oF
Spring Temper	1200 - 1800 N/mm2	174 - 261 ksi	-200 to +300 oC	-330 to +570 oF