Master Bond MB600SCN is an aqueous based, sodium silicate system with a silver coated nickel filler. It is intended for use in applications where very good shielding effectiveness is required and cost considerations might be more pronounced. Tests show that through most of the region between 1-2 gigahertz (GHz), the shielding effectiviness is a peak of 75 with a very short trough of about 40 dBs at 2 GHz. At 2 GHz, it sharply increases to almost 60 dBs, whereupon it gradually diminishes to 40 dBs at 4 GHz. Between 4-18 GHz, there is relatively minor variation with the dB level being about 45-50 up until 18 GHz. The service temperature range is also very special, ranging from 0°F to +700°F. The combination of shielding effectiveness and temperature resistance is outstanding.
Aside from its excellent performance profile, the handling is simple and safe. It is easy to brush on, and being water based, the system is relatively non-toxic. It should be noted that it is possible to spray this system as well, with the proper equipment. If sprayed on, the shielding effectiveness would be even greater than the values given above. MB600SCN will cure at room temperature in 24-48 hours or in 1-2 hours at 80°C. If curing with heat, it is advisable to ramp up the temperature over a 15-30 minute interval to prevent any possible blistering of the material. MB600SCN can be used in a wide variety of aerospace and electronic applications where a combination of robust shielding effectiveness and cost issues are important.
