ToF-SIMS characterization of a bare-spot defect in a hot-dip galvanized boron-added steel sheet  

作　　者：JIN Xinyan HONG Jufeng 

机构地区：[1]Research Institute,Baoshan Iron&Steel Co.,Ltd.,Shanghai 201999,China [2]State Key Laboratory of Development and Application Technology of Automotive Steels(Baosteel),Shanghai 201999,China

出　　处：《Baosteel Technical Research》2024年第3期1-9,共9页宝钢技术研究（英文版）

摘　　要：To determine the root cause of a bare-spot defect in a hot-dip galvanized boron-added steel sheet,we performed metallurgical characterizations using time-of-flight secondary ion mass spectrometry(ToF-SIMS)in addition to glow discharge optical emission spectrometry,field-emission scanning electron microscopy(FE-SEM),and energy dispersive spectroscopy.Mn and B enrichments on the steel surface in the bare-spot area were detected through various methods.FE-SEM revealed external oxide nodules and zinc droplets,which indicated poor wettability.ToF-SIMS further revealed considerably more detailed lateral and depth distributions of Mn,B,and Al.The formation of external Mn-B compound oxides on the steel surface prior to hot dipping,which substantially deteriorated the wettability and prevented the formation of a Fe_(2)Al_(5)inhibition layer,resulted in the formation of a bare-spot defect.ToF-SIMS mapping of Al ion proved that a slight reaction still occurred between the dissolved Al in the molten zinc bath and steel substrate,although no evident Fe_(2)Al_(5)inhibition layer formed in the bare-spot area.

关 键 词：bare spot selective oxidation galvanized steel ToF-SIMS 

分 类 号：TG142[一般工业技术—材料科学与工程] O657.63[金属学及工艺—金属材料]