(1. 南昌航空大學(xué) 輕合金加工科學(xué)與技術(shù)國(guó)防重點(diǎn)學(xué)科實(shí)驗(yàn)室，南昌 330036；
2. 北京科技大學(xué) 新金屬材料國(guó)家重點(diǎn)實(shí)驗(yàn)室，北京 100083)
摘 要: 采用脈沖激光焊接技術(shù)成功實(shí)現(xiàn)FeSiB非晶帶材的搭接，并通過熱處理方法分析接頭晶化行為。利用掃描電子顯微鏡SEM、X射線衍射儀XRD、差示掃描熱儀DSC和透射電鏡TEM等研究不同功率對(duì)激光焊縫成形、組織特征及晶化行為的影響。結(jié)果表明：當(dāng)功率低于4.8 W時(shí)，焊縫表面粗糙、熔寬小；當(dāng)功率高于9.6 W時(shí)，焊縫存在微裂紋；當(dāng)功率為7.2W時(shí)，焊縫成形良好，未見焊接缺陷。隨著功率的增加，接頭抗拉強(qiáng)度先升高后降低，最高拉伸強(qiáng)度為410 MPa，斷裂方式為解理斷裂；接頭組織主要由非晶相、樹枝晶、白色顆粒狀的結(jié)晶相組成；接頭晶化過程中先析出α-Fe(Si)相，再析出Fe2B相。
關(guān)鍵字: FeSiB非晶帶材；激光焊接；晶化行為；顯微組織
（1. National Defence Key Disciplines Laboratory of Light Alloy Processing Science and Technology, Nanchang Hangkong University, Nanchang 330063, China;
2. State Key Laboratory for Advanced Metals and Materials, University of Science and Technology Beijing, Beijing 100083, China）
Abstract:FeSiB amorphous ribbons were successfully pulse laser lap welded, and the crystallization behavior in the weld was investigated in heat treatment. The effects of pulse power on weld formation, microstructure and tensile properties were studied, and the crystallization process of amorphous ribbon was analyzed by testing technologies. The results show that the weld surface is rough and the weld width is narrow when the power is below 4.8 W. However, some microcracks are formed on the weld surface with power exceeding 9.6 W. When the power is 7.2 W, the weld quality is best without welding defects. With the increase of pulse power, the tensile strength of the joint first increases and then decreases, the highest tensile strength reaches to 410 MPa. The failure of the joints is a cleavage fracture. Moreover, the microstructure in the joint is mainly composed of amorphous phase, dendrites, crystalline phase with white particle shape. An obvious crystallization process occurs during welding, where the α-Fe(Si) phase is firstly precipitated, and then the Fe2B phase is formed.
Key words: FeSiB amorphous ribbon; laser welding; crystallization behaviour; microstructure
