金屬之加工軟化與退火硬化

Strain Softening and Anneal Hardening in Alloys

蕭勝元(Sheng-Yuan Hsiao)

指導教授 ： 楊智富

大同大學/工程學院/材料工程學系所/碩士(2007年)

摘要

本研究利用熱機處理來製備具不同預應變之四種合金，包括AZ31鎂合金、L9鎂鋰合金 、6061鋁合金及七三黃銅，探討其是否及如何發生加工軟化行為與退火硬化行為。藉由示差掃瞄熱卡計(DSC) 及高溫壓縮測試，並且配合光學顯微鏡(OM)微觀組織之觀察，探討四種合金內微觀結構之變化與加工軟化及退火硬化的關係。研究結果顯示，預應變量越大之材料其高溫強度越低，造成「應變軟化」或「加工軟化」；而退火造成材料之高溫強度上升，即「退火硬化」，而且預應變量越大之材料其「退火硬化」之效果越明顯。

關鍵字

加工軟化 ； 退火硬化

並列摘要

In this study thermomechanical processings were applied to four alloys, including AZ31 and L9 Mg alloys, 6061 Al alloy and Cu-30%Zn alloy, for the strain softening and anneal hardening studies. By using differential scanning calorimetry (DSC), optical microscopy (OM), and elevated temperature compression test. The relationships between microstructure evolution and the behaviors of strain softening and anneal hardening were examinated. The results showed that the elevated temperature strength of alloys is inversely proportional to the applied pre-strain, which leads to the strain softening effect. An anneal treatment, on the other hand, increases the elevated temperature strength of alloys, and the magnitude of anneal hardening was found to be proportional to the magnitude of pre-strain.

並列關鍵字

strain softening ； anneal hardening

參考文獻

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