| All data is for information only------(<---links) | |
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| PRODUCT DATA of AISI 440B |
| Material | AISI 440B |
| Product Datasheet | 440B |
| General Information | This is a high carbon martensitic stainless with moderate corrosion resistance good strength and the ability to obtain and keep excellent hardness (Rc 58) and wear
resistance.
Data for hardened and stress relieved |
| Precautions | Cracking may occur on heating, cooling, pickling or after welding. These steels are particularly subject to decarburization because of their high carbon content. Use of protective, on-decarburizing atmospheres in heat treatments is recommended. This steel is subject to severe embrittlement by gaseous hydrogen |
| Chemical Composition | Fe-17Cr-0.85C |
| PHYSICAL PROPERTIES |
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| Crystal Structure | Face centered cubic (fcc) |
| Specific Gravity | 7.65 |
| Magnetic Properties | Ferromagnetic |
| ELECTRICAL PROPERTIES |
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| Electrical Volume Resistivity | 6e-7 ohm.m |
| THERMAL PROPERTIES |
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| Thermal Conductivity | 24.2 W/m.K |
| Thermal Expansion Coefficient | 10.1 μstrain/°C |
| Melting Range | 1370 to 1510 °C |
| Specific Heat | 0.46 J/g.K |
| RELEVANT PROPERTIES FOR USE IN SPACE COMMUNITY |
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| General Corrosion Status | Requires specific corrosion protection |
| Stress Corrosion Status | Low Resistance to SCC: Table 3 Data Quality: Design Data |
| EMF vs SCE | -0.23 V Remark: Measured in 3.5% NaCl solution. Passive condition Data Quality: Design Data |
| Bimetallic Corrosion | Can be connected without any restriction to: Cr, Au, Ag, Gun-metal, P-bronzes, Sn-bronzes, Ti+alloys, Ni, Monel, Inconel, Ni/Mo alloys
Can be connected in a non-controlled environment to the above and Cd, austenitic cast iron, Cu, Brasses, Al-bronzes, Si-bronzes, Au, Pt, C, Rh, Sn-Pb alloys, Sn, Pb, 300 series stainless steels Can be connected in a clean room environment to above and Al-Cu alloys Needs specific measures: All others Test:ECSS-Q-ST-70C Rev.1 Table 5.1 Data Quality: Design Data |
| Machinability | Best machined in the annealed condition. Tough, stringy chips can be best handled by the use of chip breakers. Carbide or ceramic tooling is recommended |
| Welding | This alloy is not commonly welded due to its tendency to air harden. |
| FLUID SYSTEMS COMPATIBILITY |
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| Low Pressure Hydrogen (LOH2) | Fails mechanical impact |
| High Pressure Hydrogen (HIH2) | Fails mechanical impact |
| SPECIAL RECOMMENDATIONS |
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| Special Recommendations | Cracking may occur on heating, cooling, pickling or after welding. These steels are particularly subject to decarburization because of their high carbon content. Use of protective, on-decarburizing atmospheres in heat treatments is recommended. |