You’ve boarded the aircraft on your way to that sales meeting in L.A. You tuck your new Taylormade Golf driver –200 grams of ball crushing titanium salvation—into the overhead bin and settle into your seat. The Boeing 777 surrounds you with no less than 130,000 pounds of titanium structure. By weight, 9% of today’s crash free flight will be brought to you by titanium and its alloys. Time to flip your titanium carbo-nitride coated Sony cell phone to ‘off’ as the General Electric titanium turbofan engine blades spin to life. Yeah. Titanium makes life good.
The Perfect Storm
So what do aerospace engineers, golf club designers, and consumer electronics marketers find so attractive about titanium? The Earth’s natural order gave titanium all the right stuff:
It’s Light: Titanium is one of 38 transition metals on the periodic table of elements. Unlike other useful elements like iron, nickel, and cobalt, titanium lies on the extreme light end of the chart. It has relatively few electrons, protons, and neutrons –the particles that give atoms their mass. As a result, the titanium atom weighs in lighter than 36 of the 38 transition metals.
It’s so Reactive that it’s Stable. (Huh?) It’s a paradox alright, but titanium’s atomic structure makes it want to react chemically. So much so, in fact, that bare titanium reacts with oxygen in the air to form an invisible, nanometers-thin oxide layer on its surface. That layer is so tough and impenetrable it protects the underlying metal from reacting with anything else. That makes titanium incredibly stable and resistant to corrosion.
It’s Tough: Now take those lightweight atoms and stack them together to form a titanium crystal. Nature packs them together in a three dimensional hexagon--the most efficient, stable, and stress resistant of the metallic crystal structures. This gives titanium its natural strength to temperatures of about 800 degrees Fahrenheit.
Schematic representation of a Hexagonal Close Packed (HCP) titanium crystal lattice
There’s a LOT of it! Titanium is Earth’s 9th most abundant element. It’s found in almost all igneous rocks (think “volcano stuff”) and is a major export for Australia, Canada, South Africa, and the Ukraine.
So What’s it Good For?
Even in its unalloyed pure form titanium is a useful and widely applied structural metal. Add alloying elements like aluminum and vanadium, and it becomes a favored choice of engineers:
Jet engine fan and compressor blades, engine nacelles, airframe structures
Airborne weapons systems, missile components, firearms
Surgical implants, including spine, hip, knee, shoulder, and ankle components
Turbocharger compressor wheels, valves, exhaust components
Golf clubs, bicycles, tennis rackets, laptop and cell phone chassis’
Undersea surveillance devices, propeller shafts, saltwater heat exchangers
What’s in it for Me?
Any application that can benefit from titanium’s strength, light weight, corrosion resistance, and market appeal is a candidate for a precision titanium casting.
Strength-to-Weight Ratio: Titanium alloys are as strong as many common steels but 40% lighter. An as-cast titanium part provides a strength-to-weight ratio one and a half times greater than cast and heat treated stainless steel, and twice that of aluminum. This allows designers to trim weights and section thicknesses without sacrificing strength. Titanium has found most of its applications in products converted from steel & aluminum alloys.
Corrosion Resistance: Titanium is nearly as resistant to chemical attack as platinum! It finds extensive usage in seawater and chemical handling components.
Market Appeal: Companies ranging from American Express to Blackberry have spent millions of marketing dollars reinforcing the image and value associated with titanium. All manner of consumer markets have taken advantage of titanium’s ample sex appeal. It often outperforms the precious metals in the marketplace by virtue of its technical appeal.