Wear-resistant hardfacing electrode D628

Application:

Suitable for surfacing wear-resistant surfaces that withstand minor impact loads but require good resistance to abrasive wear, such as hammer heads in hammer mills and impact plates in fan mills.

Characteristics:

A graphite-coated CCrMo-type cast iron surfacing electrode. The surfacing layer consists of a high-carbon, high-chromium cast iron type with dispersed carbides, offering high hardness and good heat resistance. However, the surfacing layer is hard and brittle, with limited ability to withstand pressure and impact loads. To avoid compromising the abrasive wear resistance, use the smallest possible current to facilitate the alignment of hard-phase crystals in the surfacing layer.

Polarity:

Direct current reverse polarity (DC⁺)

Chemical Composition of Deposited Metal (%)

Hardness of Surfacing Metal

Reference Current

Welding Process Guidelines:

1. Drying requirement: Electrodes must be baked at 250°C for 1 hour before use and used immediately after baking.
2. Preheating temperature for surfacing workpiece:
400～600°C, with all rust, oil, oxides, etc., thoroughly removed from the workpiece.
3. The length of each surfacing pass should preferably not exceed 50～70mm.
4. After welding, the workpiece should be tempered at 600～700°C for 1 hour and then slowly cooled, or immediately placed in a dry and preheated sandbox or straw ash for slow cooling.