先進高強度鋼植釘銲之接合性研究

Investigation on Weldability of Advanced High-Strength Steel by Stud Welding

周柏佑(Po-Yu Chou)

指導教授 ： 黃和悅

國立虎尾科技大學/工程學院/材料科學與綠色能源工程研究所/碩士(2015年)

https://doi.org/10.6827/NFU.2015.00051

摘要

本研究主要針對析出硬化型不銹鋼銲釘與高強度鋼板進行植釘銲接合後的微觀組織及機械性質之探討。而實驗所改變的參數為彈簧壓力及充電電壓。試驗結果顯示，當充電電壓由70V增加至100V時，接合強度會跟著提升，但接合過程中，熔融金屬液的噴濺機率，也會隨著電壓的提升增大。當電極壓力調整在8kg到10kg之間，可以防止銲接品質的不一致。熔融區的沃斯田鐵相因受到急速冷卻而轉變為麻田散鐵及變韌鐵的混合組織。接合過程中，由於高強度鋼板所接受到的熱輸入量較高，其熱影響區域顯著比銲釘較寬。而植釘銲接合過程中所釋放出的電流足以將銲釘前端及部分板材熔化，因此在能量散射光譜分析的結果顯示熔融區有Cr元素的分佈，且銲接過程中的高溫，使得少量的Cr元素擴散至高強度鋼板之中。在銲釘側之介面上有Cr元素的擴散，使得該區有著較高的硬度值；由微硬度分佈曲線可觀察出，最大硬度在熔融區，對照抗拉強度後也驗證具有較佳的接合強度。

關鍵字

高張力鋼板 ； 析出硬化型不銹鋼 ； 植釘銲 ； 機械性質 ； 顯微組織

並列摘要

This study is aimed at discussing the effect on microstructure, mechanical properties, and bond stress for welding 17-4PH stainless steel and high stress steel with capacitor discharge stud welding of different parameters, such as: working pressure (6 kgf, 8Kgf and 10 kgf), electric voltage (70~ 120 V). From elongation test, the best values are obtained at the electric voltage from 80V to 100V, and three kinds of pressure parameters. The coverage of stud bead in this range is the most intact. especially at pressure of 8kgf and 10 kgf and electric voltage of 100V; which leads to better stress. But the phenomenon of liquid metal splashing gets worsen when electric voltage is over 100V; which makes coverage of welding bead incomplete and porosity increase;It also damages metal studs and sheets.After comparing average width of heat affective zoom, the metal sheets are heat effected worse than the metal stud is, which means the splashing liquid metal is from the molten metal sheets.By observing microstructure, it's found that the stud bead cooling rate is quick; the microstructure of stud bead is turned into the mix phase of martensite and bainite.

並列關鍵字

Advanced High-Strength Steel ； Precipitation Hardening Stainless Steel ； Stud Welding ； Mechanical Property ； Microstructure

參考文獻

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