齒形與模具幾何設計於精密齒輪鍛造之應用

Application of Gear Profile and Die Design for Precision Forging

簡永泰(Yong-Tai Jian)

指導教授 ： 王培郁

國立虎尾科技大學/工程學院/機械與機電工程研究所/碩士(2009年)

https://doi.org/10.6827/NFU.2009.00014

摘要

目前國內鍛造業在齒輪鍛造方面普遍存在著模具壽命及鍛品精度不足兩大問題。在齒輪鍛造過程中的主要負荷來源為工件塑流應力、工件與模具間接觸產生的摩擦力、鍛造成形後期材料可填充空間小與應變硬化效應為。尤其在材料填充最後階段，鍛造負荷越大，因此，降低齒輪成形時產生之成形負荷為模具設計首要工作。另外針對國內齒輪鍛造大多採開放模具設計，其在材料利用率與後處理加工考量上較不經濟，故解決開放模具設計問題亦為研究主題。本研究以圓柱齒輪冷間鍛造為研究對象，模具設計針對解決材料填充率、成形負荷及模具應力過大等三部分。在材料填充率部分，進行齒形腔體與沖頭突出塊設計；在成形負荷與模具應力部分，利用洩壓口設計搭配預成形衝頭、分流法與洩壓口進行研究。研究出在良好填充情況下獲得較低的模具應力之製程參數，研究過程採用Deform-3D有限元素分析軟體來進行模擬。

關鍵字

填充率 ； 成形負荷 ； 分流法 ； 洩壓口

並列摘要

Presently, there exist two main problems in the gear forging process in industry, tool life and product quality. An excessive forming loads will effects tool life, but otherwise corner filling effects product quality. During the forging process, the main forming loads came from friction force between the contact surface of billet and die, bonding ability between the atoms, and work hardness. Unfortunately, die cavity filling is relative to forming force. Therefore, how to decrease the friction force is the main subject in this study. General the forging dies are open design in industry, efficiency used of metal and production cost are no economical, so, improve the open die design also the main problem.In this study, the cylindrical gear is used as the analyzing object for forging gear. Three topical subjects for die design in this study will be focused on improving the forming load, the die cavity filling, and the die stress. The geometric design of punch, according to second stage forming, will be used to improve the die cavity filling. The geometry of pre-formed punch, and divided material flow method will be used to improve the forming load. In the process of this study, a finite elements software Deform-3D will be used to predict and improve the forming process and forming defect.

並列關鍵字

die cavity filling ； forming load ； divided material flow ； relief hold

參考文獻

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