Metal finishers and manufacturers can now reduce the hazards of caustic soda tanks and produce black oxide finishes with the Tru Temp metal finishing process. This low temperature black oxide process operates at 200° F and blackens a range of iron and non-stainless steels, including MIM parts.
The black finish produced is a satin magnetite of 0.000020" (0.5 micron) thickness, with corrosion resistance. The overall process time is approximately 20 minutes. Consequently, blackening line throughput is high and part movement can be streamlined to enhance lean manufacturing programs, the company says.
Existing black oxide lines can often be retrofitted to convert to the Tru Temp system.