ASTM CB-30 Stainless Steel Material Data Sheet (Ferritic, Cast, Annealed)

ASTM CB-30 Designation

ASTM CB-30
Condition	Annealed; furnace and air cooled
UNS number	J91803
US name	ASTM CB-30

ASTM CB-30 Typical uses

Chemical processing, food processing, heat treating, oil refining, ore roasting, power plant

ASTM CB-30 Composition detail

C (carbon)	0	–	0.3	%
Cr (chromium)	18	–	21	%
Fe (iron)	74.1	–	82	%
Mn (manganese)	0	–	1	%
Ni (nickel)	0	–	2	%
P (phosphorus)	0	–	0.04	%
S (sulfur)	0	–	0.04	%
Si (silicon)	0	–	1.5	%

ASTM CB-30 Physical properties

Density

7.45

–

7.6

g/cm3

ASTM CB-30 Mechanical properties

Young’s modulus	196	–	204	GPa
Specific stiffness	26	–	27.2	MN.m/kg
Yield strength (elastic limit)	370	–	460	MPa
Tensile strength	590	–	720	MPa
Specific strength	49.2	–	61.2	kN.m/kg
Elongation	10	–	20	% strain
Compressive strength	370	–	460	MPa
Flexural modulus	196	–	204	GPa
Flexural strength (modulus of rupture)	370	–	460	MPa
Shear modulus	76	–	80	GPa
Bulk modulus	145	–	159	GPa
Poisson’s ratio	0.275	–	0.285
Shape factor	52
Hardness – Vickers	180	–	220	HV
Hardness – Rockwell B	86	–	96	HRB
Hardness – Brinell	148	–	208	HB
Elastic stored energy (springs)	346	–	524	kJ/m3
Fatigue strength at 10^7 cycles	295	–	341	MPa
Fatigue strength model (stress range) Parameters: Stress Ratio = -1, Number of Cycles = 1e7cycles	258	–	391	MPa

ASTM CB-30 Impact & fracture properties

Fracture toughness	65	–	103	MPa.m0.5
Toughness (G)	22.1	–	50.8	kJ/m2

ASTM CB-30 Thermal properties

Melting point	1490	–	1510	°C
Maximum service temperature	760	–	773	°C
Minimum service temperature	-73	–	-43	°C
Thermal conductivity	21	–	23	W/m.°C
Specific heat capacity	450	–	470	J/kg.°C
Thermal expansion coefficient	10	–	12	µstrain/°C
Thermal shock resistance	164	–	217	°C
Thermal distortion resistance	1.81	–	2.22	MW/m
Latent heat of fusion	260	–	285	kJ/kg

ASTM CB-30 Electrical properties

Electrical resistivity	71	–	81	µohm.cm
Electrical conductivity	2.13	–	2.43	%IACS
Galvanic potential	-0.15	–	-0.07	V

ASTM CB-30 Magnetic properties

Magnetic type

Magnetic

ASTM CB-30 Optical, aesthetic and acoustic properties

Transparency	Opaque
Acoustic velocity	5100	–	5210	m/s
Mechanical loss coefficient (tan delta)	7.2e-4	–	9e-4

ASTM CB-30 Processing properties

Metal casting	Acceptable
Metal cold forming	Unsuitable
Metal hot forming	Unsuitable
Metal press forming	Unsuitable
Metal deep drawing	Unsuitable
Machining speed	25 m/min
Weldability Notes: Preheating and post weld heat treatment are not required	Good
Carbon equivalency	3.6 – 4.8

ASTM CB-30 Durability

Water (fresh)	Excellent
Water (salt)	Excellent
Weak acids	Excellent
Strong acids	Acceptable
Weak alkalis	Excellent
Strong alkalis	Limited use
Organic solvents	Excellent
Oxidation at 500C	Excellent
UV radiation (sunlight)	Excellent
Galling resistance (adhesive wear) Notes: Aluminum bronze is the most suitable mating material to minimize galling.	Limited use
Flammability	Non-flammable

ASTM CB-30 Corrosion resistance

Pitting resistance equivalent number (PREN)	18 – 21
Pitting and crevice corrosion	Medium (20-30)
Stress corrosion cracking Note: Rated in chloride; Other susceptible environments: Hydrogen sulfide	Not susceptible

ASTM CB-30 Notes

Mechanical props. may vary greatly with composition and heat treatment.  Excellent resistance to corrosion by nitric acid.

ASTM CB-30 Standards with similar compositions

India: Grade 12 to IS 3444

Italy: GX25Cr19 to UNI 3161

USA: UNS J91803

Tradenames: AFCOLOY 20, FAHRALLOY F-1800, HENRICOT HR30, KUBOTA KHR32C