Objectives
After studying this chapter, you will be able to:
• Describe the purpose of surfacing.
• Select the proper electrode based on usability and
performance capabilities.
• Indicate how to safely prepare materials for
welding.
• Describe the procedure for making surfacing
welds.
• Consider temperature, joint preparation, filler
material selection, equipment coordination,
proper shielding gases, and test welds when
establishing a welding procedure.
• Explain the criteria for determining whether
surfacing is cost-effective.
Important Terms
buildup
buttering
cladding
hardfacing
stepover distance
Surfacing
Various metals are surfaced or covered with other
metals to protect them from another material that could
cause wear or deterioration of the original part. Wear
includes abrasion, impact, heat, corrosion, or a combina-
tion of these factors. The part may be made undersize,
surfaced, then machined to size as a new part, or it may
be rebuilt from a used part. In any case, the surfacing
operation can extend the life of the part at considerable
cost savings.
Hardfacing is a special form of surfacing applied to
make a part harder as a means of reducing wear. Not all
surfacing welds are applied to make the part harder. The
welds may be applied for any of the factors stated above.
See Figure 12-1.
Several other terms are used to describe the surfacing
operation. Buttering a part is the process of surfacing an
area where materials are to be joined and a dissimilar
material is to be used for the joining. This type of weld
may also be used when two component parts are to be
welded and heat-treated to move the joint stress from the
components. Buttering is also used to obtain specific
chemical values in the final weld. Such is the case when
applying stainless steel onto carbon steel, and the final
deposit needs a considerably lower carbon content. In this
case, a different stainless steel is used for the buttering
operation than is used for the final joining weld.
Surfacing
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101
Figure 12-1. This tractor blade arm was hardfaced for
protection during loading.