Titanium - the Wonder Material

Titanium is a unique and amazing element. It is exceptionally light, lustrous and strong. It withstands the punishing stress and heat extremes of commercial and military aviation, yet is the metal of choice for the most delicate medical implants. It is remarkably durable, forming a spontaneous and protective oxide film when exposed to oxygen. And, titanium literally colors itself, bursting into a rainbow of intense, long-lasting surface finishes when anodized.

Since 1795, when it was first confirmed as an element, titanium has challenged metallurgists and artists to make use of its wide range of amazing properties. Expensive to refine and difficult to fabricate, titanium's allure continues to grow in part because it is so complex and stunning.

Virtually no other material does so much, so well, for so many. For generations, titanium has been the premiere metal for jet turbine blades. It is a vital component of every space vehicle. Its corrosion- resistance makes it indispensable in power and chemical plants, in refining and in desalinization facilities.

Titanium's strength-to-weight ratio and unusual springiness has made it popular for high performance sports equipment, eyeglass frames and replacement joints. Non-magnetic, it is the perfect material for laptop and hand-held computer cases. Its deep finishes and brilliant colors make titanium jewelry and art prized the world over.

The ninth most abundant element in the Earth's crust, titanium is widely distributed throughout the planet. Always bonded to another element in nature, it is difficult to extract from these composite ores. Though the more economically efficient FFC Cambridge Process (using feedstock titanium dioxide powder) may soon replace the complex and expensive Kroll Process (the standard for refining since 1946), titanium still commands premium prices in the global market. Ninety-five percent of all titanium refined is used in paint and coatings. But, as the world's population ages, the use of titanium in medical applications is becoming increasingly vital to our quality of life.

Titanium makes life better
The list of biologically significant benefits of titanium is long and impressive. For one, the human body will not reject it since it is physiologically inert. In fact, human tissue will actually grow into titanium orthopedic and dental implants. Furthermore, titanium joint cups are often seeded with dimpling, much like a golf ball, providing the rough surface necessary for such osseointegration to occur.

Extremely strong and light weight, titanium can be used almost anywhere in the body: maxio-facial, dental, spinal and orthopedic implants; pacemaker casings; bone screws for every joint; surgical instruments and image-guided surgery. Once implanted, it does its job well for many years. The lower modulus of elasticity of titanium allows it to closely mimic the modulus of bone; therefore, the skeletal load is more evenly distributed between bone and implant, leading to a reduced incident of degeneration from stress shielding and fractures at implant boundaries. Also, implant effectiveness and longevity can be tracked through MRI at no risk to the patient, since titanium is non-ferromagnetic.

Initially, titanium for medical implants was machined from solid bar, sheet and plate. However, over the past decade, forgings and castings have become more prevalent, offering near net-shape appliances. Manufacturers who were once limited to a minimum of mill products from which to fabricate the devices that doctors require, now add wire and billet to their inventories and create profiles and other site-specific shapes that are easily machined and polished to exact fits.

The same change has occurred in the types of titanium available for medical use. The titanium alloy primarily used for orthopedic implants is 6AL4V ELI, though other grades can be substituted when mandated by unique, implant parameters. For instance, maxio- facial procedures often employ a commercially pure grade of spring- tempered titanium better suited to cranial needs.

As we lead longer and more productive lives, the demand for medical titanium continues to grow and evolve. Today's surgeons often choose to scrape deteriorating knees and insert a titanium disc into the damaged area rather than replace the entire joint. The high- ductility of commercially pure titanium enables biomedical engineers to design more customized replacement parts. The consumer will continue to see stronger and smaller solutions to medical issues, making life better for the aging Baby Boomer population.

The present is the time to look to the future
Some pundits insist that titanium mill products are difficult to obtain. During the Cold War, the former Soviet Union actually attempted to corner the market on titanium for strategic reasons. Today, the demands of the commercial and military aviation/aerospace industries continue to drive price and supply. For years, there has been a steady expansion in the usage of titanium across the board. With no significant slowdown in sight, mills worldwide are increasing their refining capacities to meet this demand.

As the demand for titanium continues to build, medical device manufacturers need to ensure a ready supply of titanium to meet fabrication needs. Particularly for the implant and surgical industries, consideration should be given to working with a professional distribution specialist. A distributor providing a full range of value- added services can pre-grind precision bars to tolerances of 0.001-in., ready for machine shop use. Staff with years of experience in the field can lead the manufacturer through the ever-changing array of specifications. The right metal supplier will look forward into the market and put titanium in place to keep its customers' production and development projects up and running.

There is no doubt that the titanium marketplace can be difficult, but the best distributor will understand surgical needs and in turn, pattern its own inventory and buying habits around those requirements.

Titanium's place in the medical industry is well-established and expanding. Every day, a new way to utilize this marvelous element makes lives fuller and people more independent. The titanium industry and the medical profession have formed a meaningful partnership that will continue to serve us all well.TMD