Special Steel, S99
S99 has the characteristics of a nickel-chromium-molybdenum steel and is used for general aerospace use.
| Chemical Composition (Weight %) |
||||||||||||||||
| C | Si | Mn | P | S | Cr | Mo | Ni | Al | Fe | |||||||
| Min | 0.36 | 0.10 | 0.45 | 0.45 | 2.30 | 0.015 | ||||||||||
| Max | 0.44 | 0.35 | 0.70 | 0.025 | 0.015 | 0.80 | 0.65 | 2.80 | 0.050 | Bal | ||||||
| Typical Mechanical Properties (Min unless stated) | ||||||||||
| Condition | Tensile Strength, Mpa | Yield Strength 0.2%, Mpa | Elongation % | Reduction of Area % | Hardness HB | Impact izod ft. ibf | ||||
| S99A Forging | 277 max | |||||||||
| S99B Softened | 277 max | |||||||||
| S99C Soft Forgings | 1230-1420 | 10 | 363-415 | 25 | ||||||
| S99D Bright Soft | 277 max | |||||||||
| S99E HT | 1230-1420 | 1080 | 10 | 363-415 | 25 | |||||
| S99F HT Forgings | 1230-1420 | 1080 | 10 | 363-415 | 25 | |||||
| S99G HT Bright | 1230-1420 | 1080 | 10 | 363-415 | 25 | |||||
Related Specifications
40NiMoCr105, 1.6745, BS 999
Available Forms
Round bar, flat bar, forgings
| Chemical Composition (Weight %) |
||||||||
| Min | Max | |||||||
| C | 0.36 | 0.44 | ||||||
| Si | 0.10 | 0.35 | ||||||
| Mn | 0.45 | 0.70 | ||||||
| P | 0.025 | |||||||
| S | 0.015 | |||||||
| Cr | 0.80 | |||||||
| Mo | 0.45 | 0.65 | ||||||
| Ni | 2.30 | 2.80 | ||||||
| Al | 0.015 | 0.050 | ||||||
| Fe | Bal | |||||||
| Typical Mechanical Properties (Min unless stated) | |||||||
| S99A Forging | |||||||
| Tensile Strength, Mpa | |||||||
| Yield Strength 0.2%, Mpa | |||||||
| Elongation % | |||||||
| Reduction of Area % | |||||||
| Hardness HB | 277 max | ||||||
| Impact izod ft. ibf | |||||||
| S99B Softened | |||||||
| Tensile Strength, Mpa | |||||||
| Yield Strength 0.2%, Mpa | |||||||
| Elongation % | |||||||
| Reduction of Area % | |||||||
| Hardness HB | 277 max | ||||||
| Impact izod ft. ibf | |||||||
| S99C Soft Forgings | |||||||
| Tensile Strength, Mpa | 1230-1420 | ||||||
| Yield Strength 0.2%, Mpa | |||||||
| Elongation % | 10 | ||||||
| Reduction of Area % | |||||||
| Hardness HB | 363-415 | ||||||
| Impact izod ft. ibf | 25 | ||||||
| S99D Bright Soft | |||||||
| Tensile Strength, Mpa | |||||||
| Yield Strength 0.2%, Mpa | |||||||
| Elongation % | |||||||
| Reduction of Area % | |||||||
| Hardness HB | 277 max | ||||||
| Impact izod ft. ibf | |||||||
| S99E HT | |||||||
| Tensile Strength, Mpa | 1230-1420 | ||||||
| Yield Strength 0.2%, Mpa | 1080 | ||||||
| Elongation % | 10 | ||||||
| Reduction of Area % | |||||||
| Hardness HB | 363-415 | ||||||
| Impact izod ft. ibf | 25 | ||||||
| S99F HT Forgings | |||||||
| Tensile Strength, Mpa | 1230-1420 | ||||||
| Yield Strength 0.2%, Mpa | 1080 | ||||||
| Elongation % | 10 | ||||||
| Reduction of Area % | |||||||
| Hardness HB | 363-415 | ||||||
| Impact izod ft. ibf | 25 | ||||||
| S99G HT Bright | |||||||
| Tensile Strength, Mpa | 1230-1420 | ||||||
| Yield Strength 0.2%, Mpa | 1080 | ||||||
| Elongation % | 10 | ||||||
| Reduction of Area % | |||||||
| Hardness HB | 363-415 | ||||||
| Impact izod ft. ibf | 25 | ||||||
Related Specifications
40NiMoCr105, 1.6745, BS 999
Available Forms
Round bar, flat bar, forgings