Weld Overlay also known as cladding, hard-facing, weld cladding, or weld overlay cladding, is a process where one or more metals are joined together via welding to the surface of a base metal as a layer.
This is normally done to improve the material by adding either a corrosion resistant or hard-facing layer to it.
Surfaces prepared in this way can even be highly customized by layering and alloying multiple different materials together.
Hard-Facing Weld Metal Overlay Procedure (ASME BPVC Section IX)
This example to base metal AISI 4130/4140/4145 (tool joint)
- Test coupon and limits of qualification as specified in table QW-453.
- Welding variables as specified in QW-250 for the application process.
- T thickness recommends 25 mm,
Test required are given in table QW-453, note-3, 7, 8, 9.
- Liquid penetrant examination as specified in QW-195.2.
- Hardness survey, as specified in Figure QW-462.5,
- Visual examination, as note-8 in table QW-453,
- Chemical analysis (if required), as specified in Figure QW-462.5,