RG 1

HPA COBALT alloy 6B (Co-Cr-W) (UNS R30016)

Co 60, Cr 28, W 4.50, C 1.15, Si 1.1

High Performance

Alloys

RG 2

Wear Resistant (Co-Cr-W)

• Cobalt 6B is a cobalt based chromium, tungsten alloy for wear environments where seizing, galling and abrasion are present.

• 6B is resistant to seizing and galling and with its low coefficient of friction, allows sliding contact with other metals without damage by metal pick up in many cases.

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• Seizing and galling can be minimized in applications without lubrication or where lubrication is impractical. Metal seizing is similar to one metal piece building heat against another and they become "welded" together. Galling is when these "weld" areas break off and form an abrasive debris which creates additional abrasion problems.

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• Alloy 6B has outstanding resistance to most types of wear. Its wear resistance is inherent and not the result of cold working, heat treating or any other method.

This inherent property reduces the amount of heat treating and post machining. 6B has outstanding resistance to cavitation erosion. Steam turbine erosion shields from 6B have protected the blades of turbines for years of continuous service.

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• 6B has good impact and thermal shock

resistance resists heat and oxidation,

retains high hardness even at red heat

(then cooled, recovers full original

hardness) and has resistance to a variety

of corrosive media. 6B is useful where

both wear and corrosion resistance are

needed.

RG 6

Applications

• Steam turbine erosion shields, Chain saw

guide bars, High temperature bearings,

Furnace fan blades, Valve stems, Food

processing equipment, Needle valves,

Centrifuge liners, Hot extrusion dies,

Forming dies, Nozzles, Extruder screws, &

many other Misc. wear surfaces.

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• Applications for alloy 6B include half

sleeves and half bushings in screw

conveyors, tile making machines, rock

crushing rollers and cement and steel mill

equipment. Alloy 6B is well suited for valve

parts, pump plungers.

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• Wrought alloy 6B offers the ductility, fatigue resistance and toughness of a hot worked microstructure, with the heat corrosion and wear resistance of cobalt based alloy. High Performance Alloys, Inc. inventories bar, sheet, and plate. Bar can be supplied in random lengths or cut to order. Sheet and plate are offered as whole plates, can be abrasive cut, or processed further using water jet services.

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Chemistry

Tensile data

Cobalt-Chrome Carbide Fibres Matrix

Alloy

RG 10

Specifications

RG 11

Machining• Nickel & cobalt base corrosion,

temperature and wear-resistant alloys are classified as moderate to difficult when machining, however, it should be emphasized that these alloys can be machined using conventional production methods at satisfactory rates.

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• During machining these alloys work

harden rapidly, generate high heat during

cutting, weld to the cutting tool surface and

offer high resistance to metal removal

because of their high shear strengths. The

following are key points which should be

considered during machining operations:

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• CAPACITY - Machine should be rigid and overpowered as

much as possible.

RIGIDITY - Work piece and tool should be held rigid.

Minimize tool overhang.

• TOOLS - Carbide-tipped tools are suggested for most

applications. High speed tools can be used, with lower

production rates, and are often recommended for intermittent

cuts.

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• POSITIVE CUTS - Use heavy, constant, feeds to maintain positive cutting action. If feed slows and the tool dwells in the cut, work hardening occurs, tool life deteriorates and close tolerances are impossible.

• LUBRICATION - lubricants are desirable, soluble oils are recommended especially when using carbide tooling. Detailed machining parameters and general plasma cutting recommendations are presented in tables.

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More Specific 6B Machining

• Alloy 6B is generally machined with tungsten-carbide tooling, and will produce a finish of about 200-300 RMS.

• For better surface finish, this alloy should be ground.

• 6B is ground to obtain close tolerances with excellent finish properties. Do not quench dry ground material, as may cause surface imperfections. 

RG 16

HPA COBALT alloy 6BH (Co-Cr-W) (UNS R30016)

Co 60, Cr 28, W 4.50, C 1.15, Si 1.1High Performance Alloys

RG 17

Wear Resistant (Co-Cr-W)• Chemistry of AMS 5894. This material surpasses 6K with better

ductility, with the same good hardness.

• Cobalt 6BH is the same composition of Cobalt 6B, except the

material is hot rolled and then age hardened. The direct age-

hardening after hot rolling provides the maximum hardness and

wear resistance. The advantages this creates are increased wear

life, retained edge characteristics, and increased hardness. These

properties are in addition to the galling and seizing resistance of the

regular Cobalt 6B.

• Cobalt 6BH is known in the industry as a metal that retains its

cutting edge. The economic advantages are in its long wear time,

less down time, and fewer replacements

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Applications

• Steam turbine erosion shields, Chain saw guide bars, High temperature bearings, Furnace fan blades, Valve stems, Food processing equipment, Needle valves, Centrifuge liners, Hot extrusion dies, Forming dies, Nozzles, Extruder screws, & many other Misc. wear surfaces.

• Applications for alloy 6BH also include tile making machines, rock crushing rollers and cement and steel mill equipment. Alloy 6BH is well suited for valve parts, pump plungers

• Wrought alloy 6BH offers the fatigue resistance and toughness of a hot worked microstructure, with the heat corrosion and wear resistance of cobalt based alloy. High Performance Alloys, Inc. inventories sheet, and plate.. Bar can be supplied in random lengths or cut to order. Sheet and plate are offered as whole plates, can be abrasive cut, or processed further using waterjet services.

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Chemistry Tensile Data Specifications

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Machining• Alloy 6BH is generally machined with tungsten-carbide

tooling, and will produce a finish of about 200-300 RMS.. Tools for facing or boring are essentially the same except for greater clearances where needed. For best results in drilling, the drill web should be kept thin. Screw machine length, carbide tipped drills should be used. High speed taps are not recommended for Alloy 6BH but threads can be produced by EDM techniques. For better surface finish, this alloy should be ground.

• 6BH is ground to obtain close tolerances with excellent finish properties. Do not quench dry ground material, as may cause surface imperfections.

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Micrograph of strain-hardening macles in cobalt.

The creation of macles is due to mechanical polishing

followed by a stain etch.

Micrograph attack of a cobalt-chrome-carbone alloy particle.

Micrograph: attack of a cobalt-chrome-carbone alloy particle.

RG 22

Haynes® Alloy 25 (L605) (UNS R30605) Co 50.0, Cr 20.0, W 15.0, Ni 10.0, Fe 3.0 Mn 1.5

• Excellent strength for continues service to 1800 °F. Oxidation and

carburization resistance to 1900 °F. Galling resistant, with

resistance to marine environments, acids and body fluids. Non-

magnetic, even when severely cold reduced, can reach Rc 50 when

cold reduced and aged. Resistant to hydrochloric and nitric acid at

certain concentrations and temperatures, and wet chlorine

environments at room temperature.

Gas turbine engine components: combustion chambers, and

afterburners. Other uses also include: high temperature ball bearing

service, springs, and heart valves.

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• Alloy L-605 is the strongest of the

formable cobalt alloys, useful for

continuous service to 1800 °F. Because of

long and widespread use, this alloy has

been the subject of many investigations to

determine its properties over a wide range

of conditions, thus making it an unusually

well characterized material.

• Alloy L-605 is also known as alloy 25.

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• When exposed for prolonged periods at intermediate

temperatures, alloy L-605 exhibits a loss of room temperature

ductility in much the same fashion as other super alloys, such

as X or 625.

Alloy L-605 is welded using gas tungsten arc, gas metal arc,

shielded metal arc, electron beam and resistance welding.

Submerged arc welding is not recommended. Use good joint

fit-up, minimum restraint, low inter-pass temperature and cool

rapidly from welding. For maximum ductility fabricated

components should be annealed 2150 - 2250 °F, rapid cool.

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Corrosion Resistance of Alloy L-605

• Resistance to high temperature oxidation and carburization is good. The alloy, while not primarily intended for aqueous corrosion, is also resistant to corrosion by acids such as hydrochloric and nitric acid, as well as being resistant to wet chlorine solutions.

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Aluminium Nickel Cobalt (AlNiCo) AlloysTypical Magnetic and Physical

Specifications

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Typical Magnetisation Curves at Room

Temperature

RG 28