Definition - What does Weld Overlay mean?
A weld overlay is a type of cladding that uses a welding process to melt a material onto the surface of another, different material. A weld overlay is performed to protect the base material from wear or corrosive environments. The weld overlay layer is added as a cost-effective means to increase the base material's corrosion-resistance or mechanical properties.
Corrosionpedia explains Weld Overlay
A weld overlay is a popular option when trying to find a cost-effective way to enhance a material's surface properties. An expensive material can be used solely as the clad layer as opposed to making up the entire composition of the base material. Thus, the base material can be made of some cheaper material. Care must be taken to ensure that the weld overlay material is compatible with the base material to avoid failure.
Many different types of welding processes can be used for a weld overlay. These include shielded metal arc welding, gas metal arc welding and submerged arc welding, among others.
A weld overlay can be used on many different materials and components. Popular weld overlay applications include pipelines, valves, excavation equipment and other parts exposed to corrosive or wear environments.