FE-510 低合金高強度鋼與鎳基625 合金 進行多道次異金屬焊接特性與微結構之研究

Study on Welding Characteristics and Microstructures of processing Multi-steps Dissimilar Metal Welding for FE-510 Low Alloy High Strength Steel and Nickel-base Alloy 625

王星海(Shing-Hae Wang)

指導教授 ： 于劍平

崑山科技大學/工程學院/機械工程研究所/碩士(2008年)

摘要

本文係針對壓力容器用FE-510高強度低合金鋼作為容器本體材料，另以Inconel 625鎳基合金作為導入工作液體、電纜群或相關裝置之導管材料，二者以手動式遮蔽金屬電弧焊接法予以結合；另因工作環境限制、使用壽命與兼顧製造生產成本並視構件使用實況，需進行異金屬多道次重覆切割-焊接作業，囿於重覆切焊加工，因受熱輸入量影響，勢將影響母材之性質，故有其研究探討之必要性。
本研究選用FE-510碳鋼與Inconel 625合金，規劃4組實驗組，分別
進行1、3、6、9道次重覆切焊作業，藉由X-ray檢驗、金相顯微組織分析、SEM表面形貌觀察、硬度及拉伸實驗與EDS成分分析，探討原母材材質之變化。
研究結果顯示：經多道次切焊輸入熱量與空冷過程，已顯著改變
原FE-510鋼材之組織，並有偏析現象及費德曼組織之產生，Inconel 625合金之金相組織則無顯著之改變。由拉伸實驗結果得知，經9道次切焊之實驗組，其降伏及抗拉強度成明顯下降趨勢，伸長率則隨著加工次數增加而增加。另FE-510鋼材硬度先是呈現較母材為高之硬度值，後隨切焊加工次數增加，其硬度值愈低，與金相組織改變及拉伸試驗所得數據相互吻合。

關鍵字

異金屬焊接 ； 遮蔽金屬電弧焊 ； 偏析 ； 費德曼組織 ； 熱循環過程

並列摘要

This study use FE-510 high strength low alloy （HSLA）steel as pressure container base metal, and use Inconel 625 nickel-base alloy as material of working liquid、cable or related device, we combine each other by the way of SMAW ; In addition, it’s necessary to do different metal dissimilar cutting-welding process repeatedly due to the limitation of working environment, lifetime, production cost and component real operating condition. This study is necessary because of cutting-welding repeated process is influenced by the input heat and influence base metal.
This study use FE-510 HSLA steel and Inconel 625 alloy, we arrange 4 test groups and do 1, 3, 6, 9 cutting-welding process separately, we research the variation of base metal through X-ray, metallography micro component analysis, SEM appearance observation, hardness, tensileexperiment and EDS element analysis.
This study reveal original FE-510 HSLA steel composition has significantly changed and also appear segregation and Widmanstaetten structure due to the multi cutting-welding and air cooling process, Inconel 625 alloy has no significantly changed. Yield and tensile strength is
significantly decreased and elongation is increased by the process through tensile experiment following 9 times cutting-welding process. In addition, FE-510 HSLA steel hardness was higher than base metal in initial stage and
then decreased by the cutting-welding times, the results is the same as metallography and tensile experiments.

並列關鍵字

Dissimilar metal welding ； Shielded metal arc welding ； Segregation ； Widmanstaetten structure ； Thermal cycle process

參考文獻

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