With the general extension of human life span, more and more elderly people suffer from arthritis and osteoporosis, which has led to an increasing demand for orthopedic replacement devices.
The global trend of weight gain and obesity puts human bones and joints under greater pressure. In addition, the lifestyles of most people are changing, from lack of physical exercise to increased participation in sports, further increasing the demand for replacement parts of body parts. With the development of emerging economies, more and more people can afford the cost of orthopedic medical equipment. According to Global Market Insights, a global research organization, by 2024, the output value of the global orthopedic device market will grow to 50 billion euros (53 billion US dollars).
In the fiercely competitive orthopedic parts market, five major suppliers account for approximately 85% of the market share, and more than 200 other companies compete for the remaining share. In view of this fierce competition, equipment manufacturers are committed to seeking faster and more economical parts processing methods. Through the application of new materials, implants have become stronger, lighter, and can last up to 25 years in the human body. In addition, orthopedic devices are part of the personalization of the entire consumer goods market; medical device manufacturers are looking for ways to customize their products to adapt to patients' needs for body appearance and other preferences. Product diversity has become a key competitive advantage. Therefore, machine tool manufacturers seek to develop solutions that can quickly process parts with complex contours, while tool manufacturers are committed to developing tool technology that can provide higher speed and flexibility. Advanced manufacturing technology solutions include 3D printing technology for machining and advanced cooling technology.
Typical parts
Orthopedic equipment includes hip and knee replacement parts, artificial elbow and ankle joints, trauma rehabilitation equipment, spine bone plates, and various rehabilitation nails, rods and fasteners. Joint reconstruction devices account for more than 40% of the market share, most of which are hip and knee replacement parts. The key requirements for these parts are strength, reliability, lightweight, and biocompatibility.
Processing Challenge
Orthopedic accessories are usually processed from bars, castings or forgings, and then ground and polished. For hip and knee implants, the most common workpiece material is cobalt-chromium alloy, but the use of titanium alloy is also increasing. Typical cobalt-chromium alloys include CoCr28Mo6, etc., and Ti6Al4V titanium alloy is the most commonly used material.
Both materials are biocompatible and extremely hard, so they are very suitable for manufacturing orthopedic parts. However, these same properties also increase the difficulty of alloy processing. Cobalt-chromium alloy is hard, wear-resistant, elastic, and has poor thermal conductivity. This alloy may contain hard abrasive components that cause severe tool wear, and will produce tough and continuous chips. Therefore, cutting edge geometries with good chip control properties are required.
Titanium alloy is very light and very strong. It becomes hard during processing and has poor thermal conductivity. The heat is concentrated on the cutting edge and the knife surface. High temperature, high cutting force and high friction in the chip passage will cause crater wear and tool failure. The material has a low modulus of elasticity, which is quite beneficial in some implant applications, but the material will spring back from the cutting edge during processing, so it is necessary to pay close attention to the sharpness of the tool.
Coolant requirements
The materials used in the processing of orthopedic implants usually generate too much heat and therefore require the use of coolant. However, there are usually extremely strict restrictions on the use of traditional coolants to prevent contamination of orthopedic accessories. And after processing, the traditional coolant needs to be cleaned, which is time-consuming and expensive
In addition, in terms of employee health, safety and handling policies, the coolant itself can also cause environmental problems. Another cooling technology is dry cutting technology using supercritical carbon dioxide (scCo2). This supercritical scCo2 acts as a medium to deliver dry, powerful lubricants to the cutting area.
With the birth of the fusion cooling system, parts can be processed without the use of oil, emulsion or synthetic fluid.
