TRU TEMP® low-temperature, nonpolluting black oxide from Birchwood Casey Metal Finishes can give high-tension bolts and critical fasteners a protective and attractive black oxide finish. The process forms a nondimensional, deep black finish with long-term corrosion resistance. The finish also prevents galling on critical thread surfaces.

The satin black magnetite coating is 0.5 micron thick (20 millionths in) with no effect on material hardness or tensile strength. The finish withstands up to 100-200 hours of neutral salt spray (ASTM B 117) or several hundred hours of humidity (ASTM D 1748), verified by independent testing. The solution operates at only 200F and uses mild alkaline chemistry that does not embrittle the steel. The total processing time is 25 minutes, and operating costs (including chemical and heating costs) average $.01 to .03/lb of finished work. Small parts can be processed in bulk loads with larger parts finished on racks. The process can be automated through the use of a CNC-programmable hoist system.

For more information, call 952.937.7931, e-mailinfo@birchwoodcasey.comor