# 사출성형 디스크의 진동특성 향상을 위한 공정조건 제어

• 신효철 (서울대학교 기계항공공학부) ;
• 남지근 (서울대학교 기계항공공학부)
• Published : 2006.06.01
• 68 7

#### Abstract

Increased application of optical disks requires more improved dynamic stability of rotating disks. In this study, a new concept of controlling the processing conditions of injection molded disks was developed to improve vibration characteristics. The critical speed, which shows stiffness and dynamic stability of disk, is affected by the residual stress distribution; this varies as functions of distance from the gate and processing condition. The critical speed of disk was calculated with the initial stress taken into consideration, which was determined from injection molding simulation. Choosing melt temperature, mold temperature, filling speed and packing pressure as design parameters, critical speed is maximized with the method of response surface. It is shown that the stability of injection molded disk has been improved for the new condition obtained as a result of the study proposed.

#### Keywords

Critical Speed;Injection Molding;Residual Stress;Response Surface Method

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