经济型Cu-P-Cr耐候钢的显微组织及耐蚀性

Microstructure and corrosion resistance of Cu-P-Cr economic weathering steel

在0.01 mol/L的NaHSO3溶液中,测定Cu-P-Cr、Cu-P-Cr-Ni钢的极化曲线及周浸腐蚀质量损失,对其组织及耐蚀性进行研究。结果表明,Cu-P-Cr钢48 h、72 h耐蚀性略低于Cu-P-Cr-Ni钢,但随着周浸时间的加长,至96 h时,Cu-P-Cr钢质量损失率低于Cu-P-Cr-Ni钢;两种钢在72 h、96 h相对Q235钢的腐蚀速率分别为0.595、0.529和0.546、0.596。在经济型耐蚀钢中,细化原奥氏体晶粒可提高耐蚀性;通过控制连铸和连轧工艺,Cu、Cr、V和Mn协同形成复合相,抑制了单相Cu在钢的表面或晶界处富集。

Polarization curves and immersion corrosion mass loss of Cu-P-Cr and Cu-P-Cr-Ni steels were determined in 0.01 mol/L NaHSO3 solution. Microstructure and corrosion resistance of them were researched. The result shows that the corrosion resistance of Cu-P-Cr steel is lower than that of Cu-P-Cr-Ni steel under 48 h, 72 h, but as the time of cycle erosion increased to 96 h, the mass loss rate of Cu-P-Cr steel is less than that of Cu-P-Cr-Ni steel. Average mass loss rate of them is 0.595 and 0.529 respectivly at 72 h cycle erosion,0. 546 and 0.596 respectivly at 96 h. Refinement of anstenite grain size can improve corrosion resistance; synergistic effect of Cu, Cr, Mn and V can effectively restrain the single-phase Cu enrichment on surface or in grain boundaries.