Over the weekend, an article appeared in The Economist, touting An alloy of iron and aluminium as good as titanium, at a tenth of the cost.  An article like this seems to show up every 18 months or so, offering a *NEW* titanium refining technology or (this) replacement alloy, for example.

While these discoveries are important to be on our radars, for both industry and intellectual purposes, I don’t think they have an immediate impact on the titanium markets we serve.

Here is why:

  • Economics drive alloy selection, but more likely plane by plane, rather than part by part.  We are not likely to see much alloy substitution on a single part or family of parts on an already built plane.  The maintenance manual changes alone would trump any economic saving.  Imagine a new material taking 15 years to reach a significant usage rate in the aerospace sector, probably with a defense application leading the way.
  • There is an approval process.  Any new alloy needs to be approved by a committee of alloy experts at the ASTM (American Society of Testing and Materials) and their European counterparts.
  • Then, there are more approval processes.  The FAA (Federal Aviation Administration) needs to approve new alloys  for use on planes and the FDA (Food and Drug Administration) for medical applications.
  • Don’t forget about vibration.  The big problem, not mentioned in the article is not strength but crack sensitivity due to vibration.  There really is a technical measure of vibration sensitivity in metals (Do I need to say Vibranium?)  It is easy to make a stiff, metallic alloy.  Add enough oxygen to titanium and you can triple the strength.  Titanium mixed with Aluminum makes a great, strong, lighter-than-titanium, stiff intermetallic material and it is being used in carefully selected spots in airplanes.  But not in any spot that might get impacted or flexed (neither wing nor body nor rotating engine component)

I encourage you to read The Economist article, “Wings of steel” but don’t assume this new alloy is going to change the titanium/aerospace industry any time soon.

-Dick Leopold, President

–What do you think? Leave your comments below.–