铝硅镀层热成形零件表面色差分析  

Discussion on surface color difference of hot formed parts with Al-Si coating

作　　者：陈波[1] 董伊康 尹树春 翟昌源 刘涛[1] 张俊杰 CHEN Bo;DONG Yikang;YIN Shuchun;ZHAI Changyuan;LIU Tao;ZHANG Junjie(Tangshan Iron&Steel Group Co.,Ltd.,Tangshan 063000,China;HBIS Material Technology Research Institute,Shijiazhuang 050023,China)

机构地区：[1]唐山钢铁集团有限责任公司,河北唐山063000 [2]河钢材料技术研究院,河北石家庄050023

出　　处：《冶金分析》2023年第10期75-83,共9页Metallurgical Analysis

摘　　要：通过对铝硅镀层热成形钢加热工艺的现场试验,分析验证了加热时间对零件表面色差的影响,并对油品、异物污染、激光落料导致的铝硅镀层热成形零件表面色差及其影响进行分析。结果表明:在钢种、厚度规格、加热温度相同时,不同加热时间生产的零件表面会有色差,随着加热时间的延长,零件表面颜色大体上是在蓝色、灰色、黄色和棕褐色之间循环转变;在加热温度和加热时间相近时,不同钢种、厚度规格铝硅镀层热成形零件由于Fe向镀层扩散和氧化程度的差异也会导致零件表面色差;加热工艺导致的零件色差对铝硅镀层热成形零件的力学性能影响不大,但随着加热时间的增加,扩散层逐渐增厚,镀层出现疏松和孔洞。油品导致的铝硅镀层热成形零件表面色差与正常区域在镀层厚度、镀层微观形貌和表面电阻上无明显区别,对零件后续焊接和涂装防腐性能影响很小,油污、Zn粉颗粒等异物污染导致的铝硅镀层热成形零件表面色差对镀层质量影响很小。激光落料点状烧蚀导致的热成形零件表面色差需通过优化工艺控制和规范设备操作加以避免。The influence of heating time on the surface color difference of hot formed parts with Al-Si coating was analyzed and verified through the field test of heating process.Moreover,the surface color difference of Al-Si coated hot formed parts caused by oil,foreign matter contamination and laser blanking as well as their influence was analyzed.The results showed that when the steel grade,thickness specification and heating temperature were the same,there would be color difference on the surface of the parts produced with different heating time.With the extension of heating time,the surface color of the parts changed in the cycle between blue,gray,yellow and brown.When the heating temperature and heating time were similar,the surface color of Al-Si coated parts with different steel grade and thickness would be also different due to the difference of iron diffusion to the coating and iron oxidation degree.The color difference caused by heating process had little effect on the mechanical properties of the hot-formed parts of Al-Si coating.With the increase of heating time,however,the diffusion layer was gradually thickened,and the coating layer became loose and porous.The surface color difference caused by oil had no obvious difference from the normal surface in coating thickness,coating morphology and surface resistance,and had little effect on the subsequent welding and coating anticorrosion properties of parts.The surface color difference caused by oil pollution,Zn powder particles and other foreign bodies had little effect on the coating quality.The surface color difference of hot-formed parts caused by laser drop spot ablation should be avoided by optimizing the process control and standardizing the equipment operation.

关 键 词：铝硅镀层 热成形钢 表面质量 色差 油斑 金相检测 扫描电子显微镜(SEM) 能谱仪(EDS) 

分 类 号：TF7[冶金工程—钢铁冶金]