鈹銅合金與肥粒鐵不銹鋼異種金屬微弧氬銲後的顯微組織及機械性質之研究

Investigation of Microstructure and Mechanical Properties of Micro-Tungsten Inert Gas Welding on Dissimilar Metals between Beryllium Copper Alloy and Ferritic Stainless Steel

黃志仁(Jhih-Ren Huang)

指導教授 ： 黃和悅

國立虎尾科技大學/工程學院/材料科學與工程系材料科學與綠色能源工程碩士班/碩士(2017年)

摘要

本研究主要以鈹銅合金與肥粒鐵系不銹鋼進行微弧氬銲銲接合後的顯微組織及機械性質的影響。本實驗固定電流、惰性氣體流量、銲接速度及電弧長度，以改變超音波震盪輸出功率為主要參數，實驗結果顯示，其顯微組織觀察發現，在銲縫金屬中生成Fe-Cu的化合物，且未導入超音波震盪之銲件，在銲縫金屬與熱影響區沒有析出物。導入超音波震盪之銲件，在銲縫金屬與熱影響區中觀察到有不同直徑大小的球形富(Fe-Cr)σ相析出物。在超音波輸出功率55W的條件下，銲件是有較高的硬度值與較高的拉伸強度，但其延展性會下降，以上實驗結果與富(Fe-Cr)σ相析出行為有密切關係。

關鍵字

鈹銅合金 ； 肥粒鐵不銹鋼 ； 微氬氣鎢極電弧銲 ； 超音波震盪 ； 異質材料接合

並列摘要

In this paper, beryllium copper alloy and ferritic stainless steel were welded by micro-gas tungsten arc welding. The working ranges of welding parameters were fixed by conducting trial runs and satisfactory results obtained were used to conduct an experimental study.
Experiments were conducted applying ultrasonic vibration during the arc welding process and their effects on microstructure and mechanical properties of welds were presented. The observations of microstructure revealed that Fe-Cu compound in the weld metal was confirmed and no precipitation was recorded in weld metal or heat-affected zone. Spherical Fe-Cr sigma-phase precipitates of different diameters were observed in weld metal and heat-affected zone under ultrasonic vibratory condition.
The weld joints fabricated with ultrasonic output power 55W condition were found to possess comparatively high hardness value and high ultimate tensile strength, but loss in the ductility. These results were closely associated with the precipitation behavior of sigma-phase.

並列關鍵字

Beryllium Copper Alloy ； Ferritic Stainless Steel ； Micro-Tungsten Inert Gas welding ； Ultrasonic Vibration ； Dissimilar Materials Joining

參考文獻

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