Industrial Hardfacing & Welding Wire
Cobalt Base Hardfacing Alloys

Our industrial product line consists of Cobalt Base Hardfacing Alloys. We manufacture both solid and cored-wires. These products are widely used for hardfacing in the valve, lumber, and mining industries.

PMET # Trade Name Specification
PolyStel 1 Cobalt Alloy 1 AWS A5.21 & AWS A5.13: ERCCoCr-C, ERCoCr-C, ECoCr-C
PolyStel 6 Cobalt Alloy 6 AWS A5.21& AWS A5.13: ERCCoCr-A, ERCoCr-A, ECoCr-A
PolyStel 12 Cobalt Alloy 12 AWS A5.21& AWS A5.13: ECCoCr-B, ERCoCr-B, ECoCr-B
PolyStel 12H Cobalt Alloy 12 High Carbon
PolyStel 21 Cobalt Alloy 21 AWS A521 & AWS A5.13: ERCCoCr-E, ERCoCr-E, ECoCr-E

PolyStel 1

COBALT ALLOY 1 – AWS A5.21 & AWS A5.13: ERCCoCr-C, ERCoCr-C, ECoCr-C

Characteristics and Composition

Metal Cored PolyStel 1 is a cobalt-based metal cored wire. It produces a deposit that exhibits excellent abrasion and corrosion resistance for applications where severe abrasion and moderate impact is encountered. PolyStel 1M contains a higher percentage of carbides than deposits from PolyStel 6 and PolyStel 12 which contribute to the exceptional wear resistance and superior hardness of this alloy. PolyStel 1M derives its high temperature hardness and matrix toughness from the addition of tungsten. Due to the high sensitivity to check cracking, when welding this alloy proper precautions should be made to minimize cooling stresses. This alloy can be applied to any weldable steel, including all grades of stainless steel.

Solid PolyStel 1 is an excellent high temperature wear resistance alloy consisting of a rich cobalt matrix with a high degree of chromium and tungsten carbides. The alloy is excellent when used in high temperature abrasive wear applications. It can also be specified in a number of different corrosive medias such as down hole sour gas applications.

PolyStel 1 Coated Electrodes form a low carbon, austenitic deposit with excellent work hardening properties, high temperature strength, and impact resistance. Some common applications for PolyStel 1 coated electrodes include:

  • Wear pads
  • Mixer Rotors
  • Pump sleeves
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Bal288
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PolyStel 6

COBALT ALLOY 6 – AWS A5.21& AWS A5.13: ERCCoCr-A, ERCoCr-A, ECoCr-A

Characteristics and Composition

Metal Cored PolyStel 6 is a cobalt-based metal cored wire, equivalent in nominal chemical composition, physical properties, and performance properties to the Stellite 6 brand of cobalt-based metal cored wire. Cobalt alloy 6 is considered the principal cobalt alloy in terms of versatility and resistance to many forms of mechanical and chemical deterioration over an extensive temperature range. PolyStel 6 (Stellite 6 equivalent) attributes its outstanding self-mated anti-galling properties to the high alloy content of the matrix, namely the chromium carbides contained in the deposit. Popular applications for this alloy include hardfacing applications when wear is complimented by corrosion and/or elevated temperatures such as valve seats and bearing areas. This alloy an be applied to any weldable steel, including all grades of stainless steel.

Solid PolyStel 6 is designed for high temperature applications. PolyStel 6 provides excellent wear resistance in abrasion as well as in metal to metal applications. Wear resistance is provided by the complex chromium and tungsten carbides that are supported in a rich cobalt matrix. PolyStel 6 is also resistant to oxidation up to its melting range and can be satisfactorily specified in sour gas as well as other corrosive applications.

PolyStel 6 cast rods and coated electrodes are also comparable to the Stellite 6 brand products in terms of chemistry, properties and performance. Popular SMAW applications include: shear blades, fluid flow valves, extrusion screws, roll bushings, valve bearing surfaces, and other applications where high temperatures are experienced.

PolyStel products are manufactured and sold by Polymet Corporation. Stellite brand products are manufactured and sold by Kennametal, Inc. Polymet Corporation and Kennametal, Inc. are not affiliated and Kennametal does not endorse PolyStel products.

NiCoFeCrWMoAlSi
Bal325
MnNbTiTaZrCOther
1.2

PolyStel 12

COBALT ALLOY 12 – AWS A5.21& AWS A5.13: ECCoCr-B, ERCoCr-B, ECoCr-B

Characteristics and Composition

Metal Cored PolyStel 12 is a cobalt-based metal cored wire. PolyStel 12 is equivalent in nominal chemical composition, physical properties, and performance properties to the Stellite brand. PolyStel 12 cored wire meets AWS A5.21 ERCCoCr-B. It is considered an intermediate between PolyStel 6 and PolyStel 1. PolyStel 12 has a higher hardness and better resistance to all types of wear, including galling, due to the large fraction of hard, brittle chromium carbides. This alloy’s high-temperature properties (up to 1292°F) are derived from the alloy’s higher tungsten content. PolyStel 12 is mainly used in applications that require the deposit to endure abrasion, heat, and corrosion such as knife cutting edges for the timber, paper, and plastics industry. This alloy can be applied to any weldable steel, including all grades of stainless steel.

Solid PolyStel 12 is a cobalt-based care cast rod version of Cobalt Alloy 12 that has been hot forged into small diameter wire, using Polymet’s hot extruded wire process. PolyStel 12 has excellent resistance to many forms of chemical and mechanical degradation over a wide temperature range. PolyStel 12 attributes are its anti-galling properties, abrasion, corrosion resistance, and oxidation resistance up to its melting range. It can be applied to all weldable steels, including stainless steels.

ECCoCr-B, ERCoCr-B, ECoCr-B

PolyStel products are manufactured and sold by Polymet Corporation. Stellite brand products manufactured and sold by Kennametal, Inc. are not affiliated and Kennametal does not endorse PolyStel products.

NiCoFeCrWMoAlSi
Bal298
MnNbTiTaZrCOther
1.5

PolyStel 12H

Characteristics and Composition

PolyStel 12H is a high carbon cobalt-based cast rod version of Cobalt Alloy 12 that has been hot forged to a small diameter wire using Polymet’s patented hot extruded wire processing. PolyStel 12H attributes are its anti-galling properties and increased abrasion resistance while maintaining similar properties to those of Cobalt Alloy 12. It can be applied to all weldable steels, including stainless steels.

NiCoFeCrWMoAlSi
Bal299
MnNbTiTaZrCOther
1.9

PolyStel 21

COBALT ALLOY 21 – AWS A521 & AWS A5.13: ERCCoCr-E, ERCoCr-E, ECoCr-E

Characteristics and Composition

PolyStel 21 has excellent resistance to many forms of chemical and mechanical degradation over a wide temperature range. PolyStel 21 is an excellent alloy for corrosion resistance, galling, cavitation, and metal to metal wear resistance. PolyStel 21 products are equivalent in nominal chemical compositions, physical properties, and performance properties to the Stellite brand. PolyStel 21 products meet the requirements of AWS A 5.21 ERCCoCr-E, ERCoCr-E, and ECoCr-E.

PolyStel products are manufactured and sold by Polymet Corporation. Stellite brand products manufactured and sold by Kennametal, Inc. are not affiliated and Kennametal does not endorse PolyStel products.

NiCoFeCrWMoAlSi
Bal295
MnNbTiTaZrCOther