C450, XM-25, S45000, 450 Alloy, Custom 450® stainless is a martensitic age-hardenable stainless steel which exhibits very good corrosion resistance (similar to that of Stainless Type 304) with moderate strength (similar to that of Stainless Type 410).
The alloy has a yield strength somewhat greater than 100 ksi (689 MPa) in the annealed condition, but is easily fabricated. A single-step aging treatment develops higher strength with good ductility and toughness.
This stainless can be machined, hot-worked, and cold-formed in the same manner as other martensitic agehardenable stainless steels. A particular advantage is ease of welding and brazing.
C450 stainless is generally supplied in the annealed condition, requiring no heat treatment by the user for many applications. Because it has corrosion resistance like Type 304 stainless but three times the yield strength, it has been used in applications where Type 304 was not strong enough. On the other hand, it has also replaced Type 410 stainless directly on a strength basis where Type 410 had insufficient corrosion resistance. Mechanical properties will depend on the aging temperature selected.
Unlike some common PH grades such as 13-8 and 15-5, alloy 450 can be used in the annealed condition. This alloy has improved transverse properties making it suitable in many aerospace and power generation applications. Universal Stainless offers this alloy and a wide range of specs and product forms.
There are a number of other alloys that are available for specific applications.
Grade: Alloy 450 stainless
Characteristic: Similar to Custom 450 stainless, but must be aged prior to use. It cannot be used in the solutionannealed condition.
Grade: 15Cr-5Ni stainless Characteristic: Similar to Custom 630 stainless, but has better transverse ductility and toughness.
Grade: Pyromet® Alloy 350
Characteristic: Depending on heat treatment, can have an austenitic structure for best formability, or a
martensitic structure, for higher strength up to intermediate elevated temperatures.
Grade: Pyromet Alloy 355
Characteristic: Similar to Pyromet Alloy 350 but with a lower ferrite content.
| Grade | Chemical Composition WT % | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| C | Mn | Si | P | S | Cr | Cu | Ni | Mo | Nb | |
| Custom 450 | ≤0.05 | ≤1.00 | ≤1.00 | ≤0.03 | ≤0.03 | 14.0-16.0 | 1.25-1.75 | 5-7 | 0.5-1.0 | 0.35-0.75 |
| Alloy 450 | ≤0.05 | ≤1.00 | ≤1.00 | ≤0.03 | ≤0.03 | 14.0-16.0 | 1.25-1.75 | 5-7 | 0.5-1.0 | 0.35-0.75 |
| UNS S45000 | ≤0.05 | ≤1.00 | ≤1.00 | ≤0.03 | ≤0.03 | 14.0-16.0 | 1.25-1.75 | 5-7 | 0.5-1.0 | Nb >8 x (%C) |
| XM-25 | ≤0.05 | ≤1.00 | ≤1.00 | ≤0.03 | ≤0.03 | 14.0-16.0 | 1.25-1.75 | 5-7 | 0.5-1.0 | Nb >8 x (%C) |
| B50A789 | ||||||||||
| MAT 238863 | ||||||||||
| ASTM A564 | ≤0.05 | ≤1.00 | ≤1.00 | ≤0.03 | ≤0.03 | 14.0-16.0 | 1.25-1.75 | 5-7 | 0.5-1.0 | Nb >8 x (%C) |
| X5CrNiCuMo15-06 | ||||||||||
| X 5 CrNiMoCuNb 14 5 | ≤0.07 | ≤1.00 | ≤0.70 | ≤0.04 | ≤0.015 | 13.0-15.0 | 1.20-2.00 | 5.0-6.0 | 1.20-2.00 | 0.15-0.60 |
| 1.4594 | ≤0.07 | ≤1.00 | ≤0.70 | ≤0.04 | ≤0.015 | 13.0-15.0 | 1.20-2.00 | 5.0-6.0 | 1.20-2.00 | 0.15-0.60 |
| Properties | Metric | Imperial |
|---|---|---|
| Tensile strength | 986 MPa | 143000 psi |
| Yield strength (@ strain 0.200%) | 814 MPa | 118000 psi |
| Bulk modulus (typical for steel) | 166 GPa | 24100 ksi |
| Shear modulus (typical for steel) | 83.9 GPa | 12200 ksi |
| Charpy impact | 125 - 141 J | 92.2 - 104 ft-lb |
| Elongation at break (gage length is 4 times specimen diameter) | 13.30% | 13.30% |
| Hardness, Brinell (converted from Rockwell C hardness) | 278 | 278 |
| Hardness, Knoop (converted from Rockwell C hardness) | 296 | 296 |
| Hardness, Rockwell C | 28 | 28 |
| Hardness, Vickers (converted from Rockwell C hardness) | 287 | 287 |
| Properties | Metric | Imperial |
|---|---|---|
| Density | 7.80 cm³ | 0.282 lb/in³ |
Custom 450, XM-25, S45000, 450 Alloy stainless steel alloy can be hot worked by soaking at 1150-1177°C (2100-2150°F) followed by cooling and fully annealing.
Custom 450, XM-25, S45000, 450 Alloy stainless steel alloy can be cold worked using all common techniques.
Custom 450, XM-25, S45000, 450 Alloy stainless steel alloy is annealed by soaking at 1024-1052°C (1875-7925°F) for 1 h followed by quenching in water or oil.
Custom 450, XM-25, S45000, 450 Alloy stainless steel alloy is soaked at specific temperature for 4 h followed by cooling to obtain condition H900, H950, H1000, H1050 or H1150.
Custom 450, XM-25, S45000, 450 Alloy stainless steel alloy can be welded using shielded methods to reduce contamination.
Custom 450, XM-25, S45000, 450 Alloy stainless steel alloy uses feeds and speeds comparable with other martensitic stainless steels. It is preferred to use positive feeds and slow speeds to achieve good results.
| Grade | Shape | Dimensionmm | Qty.kg |
|---|---|---|---|
| C450 | Round bar | Φ120 x 1170 | 415 |
| Alloy 450 | Round bar | Φ100 x 1000 | 650 |
| UNS S45000 | Round bar | Φ55 x 1000 | 498 |
| Custom 450 | Round bar | Φ50 x 1600 | 398 |
| B50A789 | Round bar | Φ55 x 2000 | 1123 |
Steel grade
Special steel