The Design of Plastic Injection Mold for Micro Screws from Biodegradable Plastics

The design of plastic injection molds for micro screws biodegradable plastics medical product, by applying
CAD/CAM/CAE technology to design and analyze reduces the risk and reduces the time for designing and
mold making. Therefore, the results of plastic injection mold design were analyzed by the Computer-Aided
Engineering program, simulating for the flow of plastic and the filling of plastic water. Anyway, the designed
mold can be injection molded PLA plastic with the specified injection conditions from the experiment of the
actual injection mold. Furthermore, it was found that during the temperature of 195°C and the pressure of 850-900 bar, air bubbles formed inside of the workpiece. due to low temperature and low pressure, As a result, the plastic becomes viscous and does not flow as well as it should. And in the temperature range of 215° C, pressure 800-900 bar, the workpiece began to have fins, in the pressure range of 800 bar, a slight fin formed. When the pressure is increased to 850 bar, more fins are formed. And in the pressure range of 900 bar, the workpiece has increased fins throughout the workpiece. Due to the high melting temperature, the plastic becomes too liquid, the viscosity decreases. And the higher the pressure, the faster the plastic flows. This results in more burrs on the workpiece as the pressure range increases. Injection parameters temperature 215°C Injection pressure range of 850- 900 bar is the best range for injection molding of micro-screws for fastening complete biodegradable plastic bone plates.