Can Inert Coatings Be Applied To Seal Surfaces?

August 14 2015 Process Analytical


No not that kind of seal, I'm talking about mechanical sealing systems, although this guy is cuter. Protecting fittings from corrosion and keeping them inert is important, but questions arise concerning coating surface durability.

SilcoTek® coatings are proven to withstand compression and shear stress common to CF, face seal and threaded systems.  That gives customers a new option when looking for improved corrosion resistance, durability, and inertness in sampling and process systems.

Let's see how a coated face seal stands up to the stress.

First we'll examine the coated surface before sealing.


Pre_sealed_surface_2_8_10_15_2 FESEM (Field Emission Scanning Electron Microscopy) image of the coated pre-sealed surface shows the coating conforms to the sealing area.  The raised surfaces of the gland area can be seen.  SilcoTek® coatings conform to surface contours and small orifices.


Now let's make the fitting, disassemble and examine the surface.

Post_seal_1_8_10_15 After making the metal-to-metal fitting per manufacturers instructions, a second FESEM image of the surface shows no scarring or scratching, only trace particulate from the silver gasket.

Now let's scan the fitting to be sure the inert, corrosion resistant silicon surface is really intact.


Post_seal_silicon_2_8_10_15 EDS (Energy Dispersive Spectroscopy) is used to map the distribution of silicon throughout the area.  Post sealing results show the silicon surface remains intact with no major occlusions or scratches on the surface; assuring a leak free, inert and corrosion resistant surface.


Finally let's do a leak test.

For this experiment, we'll compare coated and uncoated CF vessels under heating.  As the temperature rises, leaks and surface outgassing can also increase.  SilcoTek® coatings maximize leak integrity with a very low outgas rate compared to uncoated stainless steel surfaces, even under ultra high vacuum conditions.




Learn More About Coating Sealing Surfaces