超高強度鋼電阻點銲之顯微組織與機械性質研究

Microstructures and Mechanical Properties of Resistance Spot Welded Ultra High Strength Steel

李建興(Chien-Hsing Li)

指導教授 ： 黃和悅

共同指導教授 ： 郭央諶

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(2013年)

https://doi.org/10.6827/NFU.2013.00158

摘要

本研究主要為探討三種電極頭點銲對超高強度鋼板顯微組織、機械性質及接合性能方面之影響。經實驗獲得最佳的銲接參數為電極端徑4mm、熔接時間10cycles、電極加壓力10kgf、充電電壓400V。由顯微組織分析結果顯示，因板材與板材間的接觸電阻比電極頭與板材的接觸電阻來得大，所以熱量集中在中心，使得銲核中心處的晶粒組織較為緻密，且電極頭與板材的組織則較為鬆散。經由拉剪試驗後，其破斷型態由鈹銅及鉻鋯銅電極頭進行點銲皆為典型的窩穴狀延性破斷，但當使用磷青銅電極頭進行點銲會產生脆性的破壞型態，由此可見，使用鈹銅及鉻鋯銅電極頭進行點銲，效果會比使用磷青銅電極頭進行點銲強度還要好，且發現銲點表面會含有Cu元素，其原因可能是電極頭熔融在銲點表面所造成的。

關鍵字

超高強度鋼 ； 電阻點銲 ； 銲接參數 ； 顯微組織 ； 機械性質

並列摘要

The research was focused on the effects of Ultra High Strength Steel Sheets microstructure, mechanical property, and joint performance. The experimentally obtained optimum welding parameters Electrode diameter 4mm,Welding time 10kgf,Voltage 400V.By Microstructural Analysis display ,Since the contact between the sheet and the sheet resistance of the electrode contact resistance is far greater.So the heat is concentrated in the center,makes the center of the weld nugget grain structure is more compact,and the electrode head and the plate is more loosely organized.By tensile shear test,its breaking patterns made of beryllium copper and chromium zirconium copper spot welding electrode tips are typical ductile breaking nest cryptands.However, when a spot welding electrode phosphor bronze lattice generated weak bonding, and produce ductile transfer brittle destruction patterns.Thus, the use of beryllium copper and chromium zirconium copper electrode welding , the effect than the use of phosphor bronze spot welding electrodes intensity even higher.And found that Spot Welding the surface will contain Cu elements, the reason may be fused to the Spot Welding by the surface caused.

並列關鍵字

Ultra High Strength Steel ； Resistance Spot Welding ； Microstructural Analysis ； Welding parameters ； Mechanical Property

參考文獻

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