Q235表面纳米化后耐蚀性研究  

Corrosion Resistances of Nanocrystalline Q235

作　　者：曲红波[1] 卫英慧[1,2] 侯利锋[1] 李栩[1] 李永刚[1] 

机构地区：[1]太原理工大学材料科学与工程学院,太原030024 [2]吕梁学院,山西离石033000

出　　处：《太原理工大学学报》2015年第5期499-503,共5页Journal of Taiyuan University of Technology

基　　金：国家自然科学基金资助项目:铜基合金非平衡组织塑性变形机制控制因素研究(51374151);高等学校博士点专项科研基金资助(20091402110010);山西省科技重大专项基金资助项目(20111101053)

摘　　要：利用表面机械研磨技术,在高频率(20kHz)小弹丸(直径4mm)和低频率(50 Hz)大弹丸(直径8mm)两种组合作用下,实现了Q235钢的表面自纳米化,得到晶粒尺寸相同的纳米表面;分析了纳米化前后试样在H2SO4(0.05mol/L)+Na2SO4(0.05mol/L)溶液中的腐蚀行为。结果表明,虽然纳米晶粒尺寸相同,但是两种技术条件下试样耐蚀性却相反,大弹丸低频率条件下耐蚀性提高,而小弹丸高频率条件下试样耐蚀性明显恶化。这种变化主要与粗糙度不同相关,前者粗糙度较小,表面晶粒细化,腐蚀原电池数量减少,形成的腐蚀膜较稳定;而后者表面粗糙度较大,增大了表面与腐蚀介质接触面积,腐蚀膜稳定性差。The nanosized crystalline microstructure on the surface of Q235 steel was induced by a surface mechanical attrition treatment （SMAT ） at higher frequency （20 kHz）with smaller balls（4 mm in diameter） and lower frequency （50 Hz）with bigger balls （8mm in diameter） .The corrosion resistances of the samples fabricated in a H 2 SO4 （0.05 mol/L ）＋ Na2 SO4 （0.05 mol/L ） solution were investigated .Although the nano‐crystallines obtained are the same in grain size , their corrosion resistances is different completely .The corrosion resistance of the former specimen gets worse ,while the latter’s corrosion resistance is improved .It is concluded that the difference in the corrosion resistance for the two specimens is due to different surface roughnesses .During SMAT ,a combination of lower frequency and bigger ball size led to a smaller surface roughness compared with another combination of higher frequency and smaller ball size ,thus with fewer cor‐rosion cells and were stable corrosion film .On the contrary ,for the specimen with a bigger sur‐face toughness ,the contact areas between the specimen and corrosive media are increased ,with less stable corrosion film .This research would help the nanometer materials overcome the poor corrosion resistance in the future ,and then be widely used .

关 键 词：表面机械研磨 表面自纳米化 耐蚀性 表面粗糙度 Q235钢 

分 类 号：TG113.2[金属学及工艺—物理冶金]