Alloy Grade UNS: CN7M – High Nickel Non-Magnetic

  • Overview

    CN7M is a high-nickel austenitic stainless-steel alloy specifically formulated for exceptional corrosion resistance in challenging chemical environments. The addition of molybdenum and copper enhances its resistance to sulfuric acid and various reducing chemicals, while its inherent properties make it suitable for use with dilute hydrochloric acid and chloride salt solutions. CN7M's wholly austenitic structure ensures it remains non-magnetic, even after welding. While this alloy offers excellent machinability for ease of fabrication, it requires solution annealing after exposure to elevated temperatures (800° to 1600° F) to restore optimal corrosion resistance and prevent sensitization. This combination of corrosion resistance, non-magnetic properties, and good machinability makes CN7M a valuable choice for demanding applications in chemical processing and other industries where resistance to aggressive chemicals is crucial.

  • Typical Uses

    Heat exchanger parts, flanges, pickling rolls, pump parts, tank accessories, valve components, and centrifuge parts for chemical processing.

  • MetalTek Grade

    MTEK 20

  • Poured At:

    Carondelet Division, Sandusky International Division, Wisconsin Centrifugal Division, Wisconsin Investcast Division

Similar Specifications

Cast UNS: N08007

Wrought UNS: N09020

Wrought Grade: 20Cb-3®

Cast Grade: CN7M

Cast ASTM: A351, A743, A744

Typical Chemical Composition (% by wt.)

Aluminum: n/a

Carbon: 0.07

Chromium: 19-22

Manganese: 1.5

Iron: n/a

Copper: 3.0-4.0

Nickel: 27.5-30.5

Lead: n/a

Tin: n/a

Silicon: 1.5

Zinc: n/a

Other: Mo 2-3

Minimum Mechanical Properties

Tensile, ksi

0

Tensile, MPa

0

Calculated PREn (Minimum)

0

Yield, ksi

0

Yield, MPa

0

Elongation

0%

Heat Treatment: Solution Anneal

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