the cut, providing a place for weld defects to form. These
areas should be ground to bare metal before welding.
Grease will burn and leave a residue that causes
porosity in the weld. Use degreasers to remove grease
from the weld area, and follow recommended safety
rules. In areas where parts of previous weld deposits
remain, the old material should be removed to bare mate-
rial. Inspect the material thoroughly, and repair cracks
before applying buildup or surfacing materials. Follow
safety instructions when grinding or using degreasers.
Always wear eye protection.
Welding Procedures
Each type of surfacing requires a different proce-
dure, depending on the base material and type of welding
electrode used. Figure 12-3 shows a button-type pattern
in an industrial application.
The object of surfacing is to deposit the material
into the base or buildup material with a minimum
amount of dilution to maintain the proper metallurgical
content of the filler material. The manufacturer of the
filler material specifies the type of current and shielding
Chapter 12 Surfacing 103
Figure 12-2. Chemical composition of surfacing electrodes and their applications.
Type of Electrode
Stainless steel
High percentages of manganese
and chromium
Nickel base with manganese,
chromium, tungsten, and
molybdenum
Iron base with small amounts of
tungsten carbides within the core
Application
Used as an overlay for the carbon steels for corrosion
protection. Type 309L S/S is used for the first layer, and
type 316L is used for the final surfacing weld.
Used on materials requiring protection from moderate to
severe abrasion. These electrodes generally work-
harden in use, and cannot be flame cut or machined
after welding.
Used for resistance to high heat and corrosion, with
good impact and abrasion values.
Have excellent resistance to earth wear.
Surfacing Electrode Composition
Figure 12-3. The welder is making button-type welds to reduce wear on the blade. (Eutectic Corp.)