模具壽命在鍛造過程中扮演非常重要的角色，如何提高模具壽命來減少修模成本以及縮短因修模導致耽誤生產的時間，為目前鍛造業的重要課題。本文致力於發展對於溫鍛製程的模具壽命評估方法，結合磨耗模式、磨耗試驗、以及製程模擬來分析不同的模具設計對於模具壽命的影響。利用修正後的Archard磨耗模式來預估因為高應力以及溫升造成的模具磨耗量，並進行不同溫度下的磨耗試驗及硬度試驗，可以獲得各目標材料的磨耗係數及硬度與溫度的關係。透過製程模擬，取得模具上最容易發生磨耗部位的應力值，溫度，胚料與模具的相對滑移距離，將這些資訊導入磨耗公式中，即可獲得預估的模具磨耗量。接著比較不同幾何設計的預估磨耗量，得到不同幾何設計的預估模具壽命比值，做為模具設計的依據。將本文提出的研究方法導入工業現場產線，進行不同模具設計的生產統計，得知本文方法預估的模具壽命和現場生產模具壽命有相同的趨勢。

This study focuses on developing a method of tool life evaluation for warm forging. The essential part of this method is to combine the experimental techniques, wear model and process simulation to predict how the tool geometry will affect the tool life. A modified Archard wear model is used for wear volume prediction. The wear test and hardness test are performed at different temperatures for obtaining the wear coefficient and hardness both as a function of temperature. Through the process simulation, the tool stress, the temperature distribution on the tool and the travel length of the tool-workpiece interface at the most critical part have been obtained. Then the tool wear for different tool designs is evaluated by the modified wear model. An industrial case study of stainless steel nuts warm forging is presented to demonstrate that the tool life can be increased by a better tool design, based on the tool wear evaluation proposed by this study.

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