Custom 455® alloy offers a soft, formable material that hardens with heat treatment for increased tensile strength. This material is double vacuum-melted using a vacuum induction melt followed by a vacuum arc remelt, creating a martensitic age-hardenable stainless steel.
Chemical composition
| Element | 
 ASTM F899  | 
| Carbon | 0.03 max | 
| Manganese | 0.50 max | 
| Silicon | 0.50 max | 
| Phosphorus | 0.015 max | 
| Sulfur | 0.015 max | 
| Chromium | 11.00 - 12.50 | 
| Nickel | 7.50 - 9.50 | 
| Molybdenum | 0.50 max | 
| Copper | 1.50 - 2.50 | 
| Titanium | 0.90 - 1.40 | 
| Iron | Balance | 
| Nitrogen | 0.015 max | 
| Columbium | 0.10 - 0.50 | 
Physical properties
| Metric | 
 English  | 
|
| 
 Density  | 
7.75 g/cm³ | 0.280 lbs/in³ | 
| 
 Modulus of elasticity  | 
200 GPa | 29 Mpsi | 
| 
 Electrical resistivity  | 
758 µohms*mm  | 
29.9  µohms*in  | 
| 
 Thermal conductivity  | 
18.0  W/(m*°C)  | 
10.0 BTU*in/(hr*ft²*°F)  | 
| 
 Coefficient of thermal expansion  | 
10.62 µm/(m*°C)  | 
5.9 µin/(in*°F)  | 
*Values calculated at 22 °C [72 °F]
Mechanical properties
| 
 Cold worked %  | 
 Yield strength  | 
Elongation  %  | 
| 0 | 1000 MPa [145 ksi] | 6.3 | 
| 20 | 1055 MPa [153 ksi] | 5.7 | 
| 37 | 1110 MPa [161 ksi] | 3.8 | 
| 50 | 1138 MPa [165 ksi] | 3.5 | 
| 60 | 1193 MPa [173 ksi] | 4.6 | 
| 68 | 1275 MPa [185 ksi] | 2.4 | 
| 75 | 1310 MPa [190 ksi] | 2.5 | 
| 80 | 1331 MPa [193 ksi] | 2.6 | 
| 84 | 1372 MPa [199 ksi] | 2.6 | 
| 87 | 1448 MPa [210 ksi] | 2.2 | 
| 90 | 1517 MPa [220 ksi] | 2.5 | 
| 92 | 1586 MPa [230 ksi] | 2.4 | 
| 
 *All data represent results from 25.4 cm [10 in] test gauge length.  | 
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