Mig Wires

Alloys for Wear Facing

The general term “hardfacing” means to put a protective layer of material on a surface to prolong the life of the part. A more appropriate word to use for this activity is “wearfacing.” To effectively wearface a part and extend its life, a basic understanding of hardness, types of base metals used in wearfacing, types of wear, and types of filler alloys is needed.

Hardness- To relate to hardness, reference is made to a hardness scale. The two more common hardness scales referred to in welding are the Rockwell and Brinell scales. The Rockwell C scale refers to hard metals and is abbreviated as Rc, while soft metals are indicated by the B scale. The hardness of mild steel could be indicated as Rb 89 on the B scale or as Rc 10 on the C scale. The Brinell scale is a 3-digit number prefixed with BHN for Brinell. The Brinell hardness of mild steel would be BHN 179.

The higher the hardness of a metal, the more difficult it would be to machine. The following chart indicates the machinability of the various degrees of hardness.

MG 720

• Hard surfacing electrode for corrosion resistance at elevated temperatures.
• Cobalt based product produces a flat weld with high deposition.
• Deposits are highly resistant to moderate impact, abrasion, erosion, and corrosion at elevated temps.
• For use such as: hot trimming dies, punches, slide valve gates and discharge valves.

MG 740

• Medium hardness build-up alloy for most steels.
• Economical, general purpose alloy providing high compression strength and impact wear, with moderate abrasion resistance.
• Ideal as a buffer layer for harder overlays.
• Deposits are machinable and can be forged.
• Oxy-acetylene torch cuttable deposits.
• For uses such as: rope winches, truck wheels, roll ends, tractor pads, couplings and brake drums.

MG 740 W

• Same characteristics as the MG 740, but an extremely tough build-up flux cored spooled wire and under-base for hardfacing.

MG 745

• Build-up alloy for manganese steels.
• Ideal for rebuilding manganese and carbon steel parts.
• Excellent for severe impact and moderate abrasion applications.
• Easily weldable in all positions.
• Machinable with carbide tools.
• For uses such as: rail frogs, switch points, roller crushers and crusher hammers.

MG 745 W

• Same characteristics as the MG 745, but a high alloy self-shielding flux cored spooled wire.

MG 746 W

• High deposition build-up alloy for severe impact.
• Weld deposit can be forged and flame cut.
• Spooled wire version.

MG 750

• Excellent for joining and surfacing of most steels.
• High impact resistance.
• Deposits have outstanding corrosion resistance.
• Non-cracking welds under heavy impact.
• For uses such as: railroad tracks, frogs and switches, mill hammers, joining high alloy to low alloy steel and rolls.

MG 755

• Medium hardness and impact resistance on most iron alloys.
• For carbon and alloyed steels, including cast iron and manganese steels.
• Excellent for out-of-position field work.
• Deposits are not machinable or forgeable.

MG 760

• General purpose surfacing alloy for surfaces subjected to abrasive wear and impact.
• Abrasion and crack resistant.
• Forgeable build-up deposits.

MG 765

• Severe abrasion and mild impact resistant hardfacing electrode.
• Chrome carbide weld deposit.
• High deposition rate.
• For use on carbon, manganese, and low alloy steels, as well as cast iron.
• High hardness chromium carbides located within the matrix ensure long service life.

MG 765 W

• Same characteristics as the MG 765, but in a superior high alloy flux cored spooled wire.

MG 769

• General hard-surfacing electrode for surfaces subjected to wear and abrasion.
• Basic type coating allows all position welding.
• For use on earth moving and rock crushing machinery.
• Crack free weld deposits - multi-pass capability.

MG 770

• Severe abrasion and high impact resistant hardfacing electrode with alloyed core wire.
• Chrome carbide weld deposit.
• High deposition rate with excellent slag release.
• Designed for surfaces that must resist abrasion combined with scaling, corrosion, and erosion.
• Easy to weld out of position.
• For uses such as: furnace grates, earth augers, scrapers, road construction equipment and dredger teeth.

MG 770 W

• Same characteristics as the MG 770, but a hardfacing self-shielded flux cored spooled wire.

MG 788

• Tungsten carbide composite rod for hardfacing.
• Designed for severe abrasion and low impact applications.
• Shock-resistant matrix prevents loss of large carbide chips.
• For use on steel, cast steel, cast iron, and tool steels.
• Indicates size of carbide chip, not diameter.

MG 790

• Surfacing electrode for severest fine particle abrasion resistance.
• Highly resistant to abrasion at elevated temperatures up to 870°C (1600°F).
• High deposition rate.
• Excellent weldability on AC.

MG 790 W

• Same characteristics as MG 790, but in a self-shielded, flux cored spooled wire.

MG 799

• Versatile, self-fluxing alloy with super abrasion, corrosion, and heat resistance.
• Can be used with gas, TIG, or arc welding techniques.
• Deposit has smooth surface to reduce finishing costs.
• Excellent for metal-to-metal wear applications.

MG 7065 THF

• High deposition, high efficiency tubular hardfacing electrode.
• Excellent severe abrasion resistance; medium impact resistance.
• All position AC/DC electrode utilizing very low amps.
• High deposit efficiency.
• Designed for use on cast irons, manganese steels, low alloy, cast and carbon steels.

MG 7070 THF

• Designed for all steels.
• High deposition, high efficiency tubular hardfacing electrode.
• Excellent severe fine particle abrasion resistance.
• Cr/Mo/V carbide structure suitable for high temperatures.
• All position AC/DC electrode utilizing low amperage.

MG 7090 THF

• All position AC/DC electrode utilizing low amperage.
• High deposition, high efficiency tubular hardfacing electrode for extreme abrasion wear.
• Excellent abrasion and heat resistance up to 815°C (1500°F).
• Low dilution due to low heat input of the electrode.