Introduction
CN7M is a austenitic stainless steel grade specified in ASTM A351, ASTM A743, ASTM A744 for pressure-containing cast components. Casting process options include Investment Casting, Shell Molding Casting and Sand Casting, subject to the applicable specification and component requirements.
| Field | Value |
|---|---|
| Designation | CN7M |
| Material Type | Stainless Steel |
| Sub Type | Austenitic Stainless Steel |
| Product Form | casting |
Manufacturing Process
Investment Casting
Shell Molding Casting
Sand Casting
Equivalent Grades
- GX4NiCrCuMo30-20-4 (1.4527) — EN 10283[1]
Notes
- [1] Chemical comparison (similar grade reference).
Similar Materials
N/A
Reference Standards
| Standard | Standard Title | Edition | Specification | Identifier |
|---|---|---|---|---|
| ASTM A351 | Standard Specification for Castings, Austenitic, Austenitic-Ferritic (Duplex), for Pressure-Containing Parts | 03 | CN7M | UNS N08007 |
| ASTM A743 | Standard Specification for Castings, Iron-Chromium, Iron-Chromium-Nickel, Corrosion Resistant, for General Application | 03 | CN7M | UNS N08007 |
| ASTM A744 | Standard Specification for Castings, Iron-Chromium-Nickel, Corrosion Resistant, for Severe Service | 00e1 | CN7M | UNS N08007 |
Related Casting Products
Physical Properties
N/A
Chemical Composition
| Element | ASTM A351Edition 03 | ASTM A743Edition 03 | ASTM A744Edition 00e1 |
|---|---|---|---|
| C | ≤ 0.07 % | ≤ 0.07 % | ≤ 0.07 % |
| Si | ≤ 1.50 % | ≤ 1.50 % | ≤ 1.50 % |
| Mn | ≤ 1.50 % | ≤ 1.50 % | ≤ 1.50 % |
| P | ≤ 0.040 % | ≤ 0.04 % | ≤ 0.04 % |
| S | ≤ 0.040 % | ≤ 0.04 % | ≤ 0.04 % |
| Cr | 19.0–22.0 % | 19.0–22.0 % | 19.0–22.0 % |
| Ni | 27.5–30.5 % | 27.5–30.5 % | 27.5–30.5 % |
| Mo | 2.0–3.0 % | 2.0–3.0 % | 2.0–3.0 % |
| Cu | 3.0–4.0 % | 3.0–4.0 % | 3.0–4.0 % |
Heat Treatment
ASTM A351–03 · Heat treatment
| Step | Operation | Temperature | Cooling |
|---|---|---|---|
| 1 | Heat treat | ≥ 2050 °F / ≥ 1120 °C | — |
| 2 | Quench or rapid cool | — | water quench or rapid cooling by other means |
ASTM A743–03 · Heat treatment
| Step | Operation | Temperature | Cooling |
|---|---|---|---|
| 1 | Heat | ≥ 2050 °F / ≥ 1120 °C[1] | — |
| 2 | Quench or rapid cool | — | water quench or rapid cooling by other means |
ASTM A744–00e1 · Heat treatment
| Step | Operation | Temperature | Cooling |
|---|---|---|---|
| 1 | Heat | ≥ 2050 °F / ≥ 1120 °C[2] | — |
| 2 | Quench or rapid cool | — | water quench or rapid cooling by other means |
Notes
ASTM A743 · Edition 03
[1] Heat treatment: sufficient time to heat casting to temperature
ASTM A744 · Edition 00e1
[2] Heat treatment: sufficient time to heat casting to temperature
Mechanical Properties
| Property | ASTM A351Edition 03 | ASTM A743Edition 03 | ASTM A744Edition 00e1 |
|---|---|---|---|
| Tensile Strength | ≥ 62 ksi ≥ 425 MPa | ≥ 62 ksi[1] ≥ 425 MPa[1] | ≥ 62 ksi[2] ≥ 425 MPa[2] |
| Yield Strength (Rp0.2) | ≥ 25 ksi ≥ 170 MPa | — / Not specified | — / Not specified |
| Elongation | ≥ 35.0 % | ≥ 35 %[1] | ≥ 35 %[2] |
| Yield Strength | — / Not specified | ≥ 25 ksi[1] ≥ 170 MPa[1] | ≥ 25 ksi[2] ≥ 170 MPa[2] |
Notes
ASTM A743 · Edition 03
[1] Tensile Strength/Elongation/Yield Strength: Applies only when Supplementary Requirement S12 is specified; Condition: heat treatment per; separately cast keel block per S12.2 unless S12.3 agreement applies
ASTM A744 · Edition 00e1
[2] Tensile Strength/Elongation/Yield Strength: Applies only when Supplementary Requirement S22 is specified; Condition: heat treated to the same production procedure as the casting; separately cast keel block per S22.2
Welding Conditions
N/A
Applications
Typical casting applications include pressure-containing cast components such as valve bodies, flanges and fittings, subject to grade-specific service requirements.
Last Updated: October 16, 2026