CF-3M: Corrosion Resistant Alloy Property Data

Stainless Steel SA351 CF3M, Butterfly valve

DESCRIPTION
CF-3M is a Fe-Cr-Ni-Mo alloy that is the cast equivalent of wrought, low carbon, AISI 316L stainless steel. The low carbon content of the alloy results in greater resistance to sensitization of the welds. Consequently, it is most commonly used in applications where post-weld heat treatment cannot be applied. Optimum corrosion resistance is reached after solution annealing at 1900 to 2050oF followed by rapid cooling. It has good resistance to organic acids and salts, sulphuric and sulfurous acids, phosphoric and phosphoric-sulphuric-hydrofluoric acid mixtures, sulfate and sulfite liquors, seawater and other chloride solutions, sodium hydroxide and steam. A modified form of the alloy, known as CF-3MA, has higher strength than the normal CF-3M. This is achieved by balancing the composition to produce a higher range of ferrite than the 20% present in the CF-3M grade.

RELATED SPECIFICATIONS
ASTM A351(CF3M and CF3MA), A743(CF-3M), A744(CF-3M), A 451 (CPF3M), J92800 Nearest wrought grade: AISI 316L.

COMPOSITION
                 C         Mn     Si         Cr      Ni    Mo         P      S
Min %                                       17.0    9.0    2.0       
Max %    0.03    1.50    1.50    21.0    13.0    3.0    0.04    0.04

APPLICATIONS
Impellors, propellors, pump casings, suction manifolds and valve bodies.

PRODUCT FORMS
Horizontal and vertical centrifugal castings; static castings.

PHYSICAL PROPERTIES
Density (lbs/in3)      0.280
Liquidus(oF)            2600
Thermal Conductivity     9.4 @ 212oF;
(Btu/h/ft2/ft/oF)              12.3 @ 1000oF
Thermal Expansion         8.9 @ 70-212oF
(10-6in/in oF)                  9.7 @ 70-1000oF
Magnetic Permeability    1.2 to 3.1

MECHANICAL PROPERTIES
(Typical Values at Room Temperature - Solution Annealed >1900oF, Water Quenched.)
ASTM Specs A351 and A743
                                   CF-3M    CF-3MA      A743 CF-3M    A351CF-3A
U.T.S.           K.S.I.    80               90                     70 Min         77 Min.
Y.S.               K.S.I.    38               45                      30 Min        35 Min.
Elong.            %         55               45                      35 Min         35 Min
Brinell           H B      150            170       
Charpy 'V'    ft-lbs    120              100       

WELDABILITY
CF-3M may be welded by the SMAW, GTAW and GMAW processes.
Electrodes    308Mo, 316, 317, 316L, 308MoL.
Preheat    Not required.
Post weld heat treatment Not normally required

Source: Kubota Metal Corporation