Crucible 174 SXR
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Crucible 174 SXR is a premium quality precipitation- hardening stainless steel designed for use as rifle barrels. It is a modification of Crucible’s 17Cr-4Ni which offers substantially improved machinability without sacrificing toughness. Its excellent corrosion resistance approaches that of a 300 series austenitic stainless steel, while its high strength is characteristic of 400 series martensitic stainless steels. At similar hardness levels, Crucible 174 SXR offers greater toughness than either the 410 or the 416 stainless steels which are commonly used for rifle barrels.
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Typical Chemistry |
Carbon |
0.02% |
Chromium |
15.25%
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Nickel |
4.80%
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Copper |
3.50%
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Manganese |
0.60%
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Silicon |
0.50%
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Columbium + Tantalum |
0.20%
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Phosphorus |
0.025% |
Sulfur |
0.02%
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Nitrogen |
0.015%
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Iron |
Balance |
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- Crucible 174 SXR is a precipitation-hardening stainless steel which is capable of high strength and high hardness after a relatively simple heat treatment. This grade is martensitic and therefore magnetic in both the solution treated and precipitation-hardened conditions. It has high resistance to crack propagation and its corrosion resistance is superior to the standard martensitic 12 Cr hardenable stainless steels. Because it is hardened by a single low-temperature precipitation-hardening heat treatment, scaling and distortion are virtually eliminated. This enables material to be finish machined to close tolerances prior to heat treatment.
Crucible 174 SXR meets the industry specifications for 17Cr-4Ni. By closely controlling the chemical composition within the standard range, Crucible 174 SXR shows a significant improvement in ductility over standard 17Cr-4Ni in all conditions, but especially in the solution-treated condition. In addition, the steel is markedly tougher than conventional 17Cr-4Ni as measured by Charpy impact tests. Crucible 174 SXR barstock is normally supplied in the solution treated condition (Condition A) ready for fabrication and subsequent precipitation hardening by the customer. However, it can be supplied in any of the several hardened conditions (Condition H’s).
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- Grade
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Typical HRC |
- Typical
Charpy V-Notch
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174 SXR (H 1025) |
38 |
40 ft-lbs
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174 SXR (H 1075) |
36 |
43 ft-lbs
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174 SXR (H 1150) |
33 |
100 ft-lbs
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410 |
40 |
35 ft-lbs
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410 |
35 |
25 ft-lbs
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410 |
30 |
70 ft-lbs
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416 |
30 |
20 ft-lb
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Solution Treatment: 1900°F, 30 minutes Air Cool or Oil Quench. (Material supplied in Condition A is in the solution treated condition. It does not require solution treatment prior to precipitation hardening.) Precipitation Hardening: Material supplied in Condition A can be heat treated at different temperatures to develop a wide range of properties. A number of standard heat treatments have been developed:
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Condition
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Hardening Temp. °F
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Time (hr.)
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Cool
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HRC
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H1025
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1025
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4
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Air
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38
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H1075
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1075
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4
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Air
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36
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H1100
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1100
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4
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Air
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35
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H1150
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1150
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4
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Air
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33
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H1150M
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1400 1150
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2 4
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Air Air
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– 28
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Double H1150
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1150 1150
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4 4
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Air Air
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– 31
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Note: Properties shown in this data sheet are typical values. Normal variations in chemistry and heat treatment may cause deviations from these values.
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