The scene has changed due to the advancements in medical technology. In addition, the prognosis is better for those who are physically traumatized due to sports or incorrect or over exertive exercise habits or due to road traffic and other accidents. Thus, the implants are now expected to serve for much longer period. The development of appropriate material with high longevity and excellent biocompatibility is highly essential.
A laboratory-type CNC press comprises an injection molding machine, a hot chamber and an annealer. The injection molding machine is of type of cold injection molding ( Figure ). The molding process is as follows: powder of titanium was first mixed with an appropriate quantity of binder, and then dispersed into a certain volume of liquid medium; fine particles were then drawn into the mold cavity by electric force field; molds were then placed on the aluminum moldboard, and liquid metal was poured into the mold cavity; and the metal in mold cavity was heated to a predetermined temperature to synchronously solidify the metal in the mold cavity; the hot mold was removed from the mold board, and the molded body was pierced with a nail or a pin; the molded body was then drawn out of the mold cavity; and the molding body was mounted in hot air for glazing; the glazing mold was then heated to a predetermined temperature for sintering the interior part; and the molded body was finally ejected from the mold head.
The setting up of a computer-controlled molding process for the production of titanium material has been achieved and a pilot production has been carried out. This process is based on the computer control of the positioning of injection nozzle and the feeding of liquid metal in the nozzle. Three manual operations are replaced by four automatic operations whenever production is undertaken.
TABLE 8 Effect of Alloy Design on Mechanical Properties of Ti-6-4-4-2-2 NP Casting (Hefting et al., 1997). Properties are compared to conventional CP Ti and the conclusions are listed below; 7211a4ac4a