Properties
Talonite® is a Cobalt -Chromium alloy. When it is made the Chromium and Molybdenum combine chemically with the carbon to form Chromium carbide and Molybdenum carbide. The cobalt forms a soft and strong matrix that holds the carbide grains in place. This means that a Rockwell or other hardness tests will test the matrix and give relatively low readings however the hardness and wear resistance is in the carbide particles.
If tool steel stays sharp for 6 - 8 hours then Talonite ® will retain an edge for 12 - 14 days.
Lubricity
Talonite® is much slicker than steels so it wears much longer. Talonite® has outlasted Stellite 6K by 35% in wear tests. These were wear tests in a cereal manufacturing plant. The abrasive substance was organic fibres in corn and wheat. Talonite® rates much higher than steel and much closer to diamond or Teflon in slickness.
Talonite® is slicker so it also cuts faster and easier. Machinery’s Handbook, 24th Edition says that these alloys can be run 20% to 50% faster than high-speed steels when cutting.
Corrosion
The development of high speed and high temperature turbines for jet engines led to the development of a new kind of Haynes alloy with corrosion resistance. A good way to understand the corrosion resistance of Talonite® is to think of a Navy fighter that sucks sand into the engine flying out of Pensacola and sucks seawater in landing on a carrier.
Talonite® is used regularly in applications such as sawing green lumber in a sawmill. Highly corrosive organic acids, high heat from friction and cut lengths of millions of inches as well as interrupted cuts and intense thermal cycles, (extremely hot in the cut and out into flood coolant)
Talonite® makes an excellent dive knife. It does not rust by the usual definitions, however it is technically susceptible to chemical attack. Generally it requires something on the order of a boiling 20% acid solution such as hydrochloric acid or sulfuric acid for weeks or months. Talonite® was developed for and is extremely suitable for hard service applications in rough environments such as salt water. If your instruments were really good you might detect corrosion in salt water after a thousand years.
Talonite® Compared to Steel
Talonite® is an alloy that is primarily cobalt and chrome with only a very small percent of iron in it. It is not steel since steel is iron based. Steel is iron with a very little bit of carbon in it. (Iron with 0.1 - 0.3% carbon and a maximum of about 2.5%).
Talonite® is very different than steel and cannot be compared one to one with steels. Talonite® has a lower Rockwell than some steels but it contains carbide grains. It is softer on a Rockwell test but much more wear resistant than steels. Besides the hardness of the carbides it also has about a 30% greater lubricity. Talonite® can be sharpened to a razor edge as well as any other material, however it will cut much better than other materials with an equivalent edge because it is much slicker. Steels will have a greater tendency to grab in the cut. The grabbing will create more work and dull the edge faster. On a lubricity scale, Talonite® is much closer to Teflon® or diamond than it is to steel.
Talonite® is not a stainless steel alloy although it has some of the same components as stainless steels. Talonite® is generally much more corrosion resistant than stainless steels are.
Catalytic Chemistry
The metals that go into an alloy are only part of what determines the quality of the alloy. Time, temperature, number of steps, kind of steps, and quality of ingredients also determine the quality.
Talonite® is superior because it is made using more sophisticated chemistry. A catalytic additive can give an alloy smaller carbide grains, which makes it more wear resistant. A catalyst can alter the structure of the cobalt bonding mechanisms so they grow more slowly and more evenly, which gives a structure that is both softer (more impact resistant) and tougher (more resistant to tear or rupture).
Mechanical and Other Properties
The following values based on tests done on: Solution heat-treated at 1232°C, air cooled, 4.8 mm thick sheet
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Density
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8.387g/cm3 (0.303 lb/in3)
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8.387g/cm3 (0.303 lb/in3)
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Hardness, Rockwell C
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42-49
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37
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40-46
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Ultimate Tensile Strength
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195,000psi
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144,000psi
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176,000psi
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Yield Strength
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121,000psi
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89,000psi
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102,700psi
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Elongation %, break
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4.50%
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10%
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4%
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Modulus of Elasticity
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30,600ksi
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31,000ksi
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-
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Heat Capacity
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0.101 BTU/lb.°F
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0.101 BTU/lb.°F
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Thermal Conductivity
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103BTU.in/ft2.hr.°F
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103BTU.in/ft2.hr.°F
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Melting Point (°C)
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1454°C (2650°F)
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1310°C (2390°F)
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Electrical Resistivity
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546 Ω/cir. Mill ft
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546 Ω/cir. Mill ft
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546 Ω/cir. Mill ft
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Magnetic Permeability
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<1.2 @22°C at 200Oe
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<1.2 @22°C at 200Oe
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<1.2 @22°C at 200Oe
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Cold Weather Applications
This alloy does not show any significant changes in strength or use at reasonable operating temperatures. This alloy is used successfully in applications such as knives and saws in unheated saw and paper mills in locations such as Alaska, Upper Canada and Upper Michigan.
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