Eagle 646 Tool Steel Hardfacing Rod | 60–64 HRC

Eagle 646 is recommended for:

Dies
Punches
Shears
Debarker knives
Mill cutters
Planing tools
Tool steel wear surfaces
Cutting and shearing components
High-speed and hot-work tooling

Designed for applications where very high hardness and edge retention are required.

Clean the weld area thoroughly and remove fatigued or damaged metal before hardfacing. Use grinding where practical, or Eagle 188 airless gouging electrodes where additional material removal is required.

Use the lowest effective amperage while maintaining a medium arc length. Apply stringer beads to help reduce heat input.

On low-carbon steels, a minimum of approximately three layers may be required to overcome dilution and achieve the desired deposit properties.

When welding on tool steel, preheat the component to approximately 1000°F.

Eagle 646 is a premium tool steel hardfacing electrode designed for high-speed and hot-working steel applications.

Its high-hardness deposit provides excellent wear resistance and edge retention on tooling and cutting surfaces. As welded, Eagle 646 deposits approximately 60–62 HRC, with hardness increasing to approximately 62–64 HRC after heat treatment.

Why Eagle 646?

Very high hardness — 60–62 HRC as welded, with the ability to reach approximately 62–64 HRC after heat treatment.
Excellent edge retention — ideal for dies, punches, cutters and other tooling where maintaining a hard working edge matters.

Designed for tool steels — specifically suited to high-speed and hot-working steel applications.

All-position capability — useful for repair and hardfacing where components cannot always be positioned flat.

646 or Shearbuild 45?

Choose Eagle 646 when you need maximum hardness and edge retention on tool steels, dies, punches, cutters and similar tooling.

Choose Shearbuild 45 when the application involves more repeated impact, metal-to-metal wear and multi-pass rebuilding, where a tougher, less brittle deposit is preferred.

In simple terms:
646 = maximum hardness + edge retention
Shearbuild 45 = toughness + impact + multi-pass build-up

3/32" / 2.50 mm — 45–90 A
1/8" / 3.25 mm — 90–125 A
5/32" / 4.00 mm — 130–180 A