Introduction
CK20 is a austenitic stainless steel grade specified in ASTM A351, ASTM A743 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 | CK20 |
| Material Type | Stainless Steel |
| Sub Type | Austenitic Stainless Steel |
| Product Form | casting |
Manufacturing Process
Investment Casting
Shell Molding Casting
Sand Casting
Equivalent Grades
N/A
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 | CK20 | UNS J94202 |
| ASTM A743 | Standard Specification for Castings, Iron-Chromium, Iron-Chromium-Nickel, Corrosion Resistant, for General Application | 03 | CK20 | UNS J94202 |
Related Casting Products
Physical Properties
N/A
Chemical Composition
| Element | ASTM A351Edition 03 | ASTM A743Edition 03 |
|---|---|---|
| C | 0.04–0.20 % | ≤ 0.20 % |
| Si | ≤ 1.75 % | ≤ 2.00 % |
| Mn | ≤ 1.50 % | ≤ 2.00 % |
| P | ≤ 0.040 % | ≤ 0.04 % |
| S | ≤ 0.040 % | ≤ 0.04 % |
| Cr | 23.0–27.0 % | 23.0–27.0 % |
| Ni | 19.0–22.0 % | 19.0–22.0 % |
| Mo | ≤ 0.50 % | — / Not specified |
Heat Treatment
ASTM A351–03 · Heat treatment
| Step | Operation | Temperature | Cooling |
|---|---|---|---|
| 1 | Heat treat | ≥ 2100 °F / ≥ 1150 °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 | ≥ 2000 °F / ≥ 1093 °C[1] | — |
| 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
Mechanical Properties
| Property | ASTM A351Edition 03 | ASTM A743Edition 03 |
|---|---|---|
| Tensile Strength | ≥ 65 ksi ≥ 450 MPa | ≥ 65 ksi[1] ≥ 450 MPa[1] |
| Yield Strength (Rp0.2) | ≥ 28 ksi ≥ 195 MPa | — / Not specified |
| Elongation | ≥ 30.0 % | ≥ 30 %[1] |
| Yield Strength | — / Not specified | ≥ 28 ksi[1] ≥ 195 MPa[1] |
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
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 13, 2026