SilcoTek Coating Blog

Wear Resistant CVD Coating Tests Put Dursan on Top

Written by Dr. David Smith | March 30 2018

We smashed stretched and burned our impact resistant coating.  What we found was alarming, for the other test coupons....

It looks like our R&D staff had some pent-up anger lately.  We set them lose on our Dursan® coating so they could let off some steam (and keep the rest of the the team safe)!  They compared the coating durability, strength and bend resistance of Dursan® in what looked more like a medieval torture chamber than a lab.  Did the coating survive?  Let's find out.*

In this blog post your will learn:

  • How Dursan withstands high stress and remains intact.
  • How Dursan holds up to wear.
  • How Dursan withstands high temperature exposure.

What about wear resistant CVD coatings?

CVD coatings are thin but are they wear resistant?  We tested Dursan vs. uncoated stainless steel in a comparative pin-on-disk wear test. We found Dursan was more wear resistant than stainless steel and had higher surface lubricity, making the wear resistant coating ideal for valve components and wear prone surfaces.

Read the wear resistance report.

 

Want to see more material tests of our coatings?  Here's a great webinar that tests the mechanical properties and material limits of our coatings.  The webinar is focused on semiconductor applications but the data applies to all coating applications.

 

Mechanical properties of coating.

We tested the tensile strength of an uncoated 316 stainless steel 1in diameter rod and a Dursan coated 316 stainless steel rod.  We pulled the samples to ultimate tensile strength and Bang! Rod failure!  Wow that was cool!  Here's a video of a tensile test, it's not our test, but it does give you a good idea of how the test was performed. 

Results showed the Dursan coating performed at or above the uncoated coupon in ultimate tensile performance; failing at 96,000 psi at ambient temperature.

We tested again at 450ºC to see if the relative tensile test changed.  The ultimate tensile strength dropped as expected, but the Dursan coated rod fared a bit better, with a 20% drop compared to a 23% drop for the uncoated rod.

Comparative tensile strength    
     
Material Ambient Tensile Strength 450C Tensile Strength
316 stainless steel 93000 71500
Dursan® Coated Stainless Steel 96000 76500

Read the complete report to compare the yield data and test specifications.

 

Read The Complete 

Tensile Strength Test Report

 

The Crush Test...Ouch!

We crushed a coated foil sheet and a stainless steel ball to see if the coating would stay put.  Here's the video of our crush tests.  First we compared a coated stainless steel foil sheet and a painted foil sheet.  We balled them up to see if the coating would flake.  Nope!

Then we got out the press and crushed a coated stainless steel ball to see if we could get the coating to say uncle.  Again we were amazed at the durability of the coating.  Finally we coated a tube to see if the coating failed.  You guessed it, the coated tube bent without a problem.

 OK, Let's Turn UP The Heat!

You guessed it we torched the coating to see if it would burn, flake, oxidize or explode.  I was hoping for explode but no luck!  In fact the coating took the flame test in stride.  Here's the video.  Watch how the surface glows bright red yet after cool down the coating looks unscathed with no oxidation or damage.  The stainless steel coupon was severely oxidized after the heat exposure and the PTFE sample really took it on the chin. 

Want more data about SilcoTek coatings and applications?  Go to our new E-book library and download our easy to read e-books.  You'll get lots of application and coating data and great tips on how to make your process or products better.

 

* Photo Courtesy of NASA.