Electric motor hairpin processing

Electric vehicle motors use copper “hairpins”, rectangular copper wires up to 6mm wide coated with a dielectric enamel (PEEK, PFA-PI, PA), to provide electrical isolation; this enamel must be partially removed so that the hairpins can be welded for electrical contacting.

Unlike mechanical methods, laser processing is contactless, without ablation or loss of copper, and with very little downtime or tooling needed for any changes.  A galvanometer scanner passes the laser beam over the required area, turning the hairpin midway through to process all sides, while leaving the copper undamaged.

Enamel ablation using our CO₂ lasers is a very fast process.  Removal rates depend on the type and thickness of coating, as well as the coating method (cross layer), but there is no material loss (cost of copper) when a CO₂ laser is used.