MIL-R-81294 Figure 1 dimensions for dissimilar metal test panels

MIL-R-81294 §4.6.4.2 Corrosion Couple Test Panels

Metal test panels used in military specification MIL-R-81294 §4.6.4.2 (Corrosion test for dissimilar metals). This test uses ten test panels made from 7075-T6 clad aluminum, AZ31B magnesium**, 1020 cadmium plated steel, and 6Al-4V titanium. Each panel is 3" x 4". Three aluminum and two titanium panels have four holes drilled as shown in Figure 1. Two magnesium, two steel and one titanium panel have three holes drilled per Figure 1 Note 3. The two sets of panels are fastened together in bimetallic couples and tested per MIL-R-81294.

**Note that the MIL-M-3171 chrome pickle treatment for the magnesium panels specified in MIL-R-81294 is no longer used or commercially available in the US. Metaspec can provide untreated magnesium panels or an alternate surface treatment instead of MIL-M-3171.