A recession in the aerospace industry in 1992-93 was the spur that convinced titanium producers to actively pursue other markets, including sports and medical applications. Industry leaders quickly began research to position titanium in what were termed "second-tier" markets.
Lightweight, with a high strength-to-weight ratio and able to absorb shock and dampen blows, titanium quickly found usage in bicycle manufacturing and in such equipment as baseball bats, hockey sticks and golf club shafts. But it was titanium's essential biocompatibility that ensured its acceptance in medical circles.
Beginning in the 1990s, medical-grade titanium alloys began replacing stainless steel and aluminum in surgical procedures and implants, and titanium also made major strides in the market for medical and surgical instruments.
A wide range of titanium alloys allowed the medical community to specify different alloys for different applications. Where formability was a crucial element of the application, researchers and designers specified high-ductility commercially pure titanium, while fully heat-treatable alloys are used for strength and shape-memory alloys are increasingly used in medical machining.
Orthopedic medical device manufacturers were the first to discover the benefits of medical-grade titanium. The first experiments on the utilization of titanium alloys in orthopedic implants date back to the late 1950s. Designed to conform to the complex shape of bones and joints, titanium proved to be a perfect material for fashioning artificial hips and knees.
Titanium is rarely rejected by the human body and it is compatible with magnetic resonance imaging (MRI) and computed tomographic (CT) imaging. In hip replacement surgery, for example, titanium is used in the femoral stem, as well as the titanium shell that lines the acetabular cup that is screwed into place in the hip bone, and a removable insert in the hip socket is protected by a titanium liner.