Alloy 455 is an alloy melted by several sources. Custom 455® is a trademarked name of Carpenter Specialty Alloys. It is a martensitic age-hardenable stainless steel that offers a unique set of qualities. This alloy is double vacuum-melted using a Vacuum Induction Melt (VIM) followed by a Vacuum Arc Remelt (VAR).
AMS 5617G #1 | |
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Carbon | 0.03 |
Manganese | 0.5 |
Silicon | 0.5 |
Phosphorus | 0.015 |
Sulfur | 0.015 |
Chromium | 11.0-12.5 |
Nickel | 7.5-9.5 |
Molybdenum | 0.5 |
Copper | 1.5-2.5 |
Titanium | 0.9-1.4 |
Iron | Balance |
Nitrogen | 0.015 |
Columbium | 0.50 |
Density | 0.280 lbs/in3 |
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Modulus Of Elasticity | 29 Mpsi |
Electrical Resistivity | 758 µohms-mm |
Thermal Conductivity | 18.0 W/mK (100°C) |
A reducing atmosphere is preferred for thermal treatment, but inert gas can be used. Alloy 455 will fully anneal at 950-980°C in just a few minutes. Alloy 455 can minimally age harden with a loss in ductility, when held for prolonged periods at 370C-540°C. Original hardness can be restored by heating at 590°C.
Alloy 455 is a great material in that you can fabricate a part from material at a lower ultimate tensile strength and then heat treat it to a much higher strength. Unlike many other heat treatable alloys, Alloy 455 has good oxidation resistance at room temperature. Primary end applications are: needles, stylets, pins and springs.
%CW | Y.S.(psi) | % Elongation (10" gauge length) |
---|---|---|
0% | 145,000 | 6.3% |
20% | 153,000 | 5.7% |
37% | 161,000 | 3.8% |
50% | 165,000 | 3.5% |
60% | 173,000 | 4.6% |
68% | 185,000 | 2.4% |
75% | 190,000 | 2.5% |
80% | 193,000 | 2.6% |
84% | 199,000 | 2.6% |
87% | 210,000 | 2.2% |
90% | 220,000 | 2.5% |
92% | 230,000 | 2.4% |
Values are typical and may not represent all diameters. Test method will affect results.
Stainless steels develop a highly polished appearance as they are drawn to fine diameters. Surface roughness can be less than 5 RMS when processed using SCND* dies and measured with a profilometer. Diameters over 0.040" are finished with polycrystalline dies and exhibit a rougher surface than natural diamond dies. Diameters over 0.100" will have an even rougher surface because they are drawn with carbide dies.
*SCND means single crystal natural diamond.