Marking Processes for Casting and Forgings

January 2008

Traceability of castings is critical in many industries now to enable them to be tracked throughout the production process from casting to machining, through to inspection, final assembly and testing.  The castings may need to be marked with human readable data such as a serial or part number, a machine readable 2 dimensional data matrix (DMx) code or a coloured dot mark for simple identification of a pass or fail when testing.  Logos and graphics can also be easily marked.  Marks can be made on flat, curved and undulating surfaces.

There are a variety of marking methods that can be adopted for marking castings in either machined or un-machined states. Two of the most popular processes for marking castings and forgings are electrochemical oxide (high contrast black mark) or etch (etch below surface) marking and dot peen (dot marking/ indent marking).