高强度耐大气腐蚀钢中稀土提高耐蚀机理研究

Mechanism of Atmospheric Corrosion Resistance of RE in High Tension Weathering Steel

采用SEM、XRD、电化学阻抗和干湿周浸实验法,研究稀土对高强耐候钢耐大气腐蚀性的影响。稀土净化钢液,变质夹杂,改善了点蚀和晶间腐蚀。钢中固溶稀土提高钢基体的耐蚀性并促进稳定致密锈层的形成。稀土微合金化作用提高高强耐候钢的耐大气腐蚀性能。

The influence of rare earths on the atmospheric corrosion resistance of high tension weathering steels was studied by SEM, XRD, dry - wet immersion test and electrochemical impendence methods. The addition of RE in steel has effect of purify molten steel and metamorphose inclusions, which result in the improvement of pointed and grain- boundary corrosion. The results also indicate that the RE dissolved in steel can increase the corrosion resistance of matrix and promote the formation of the steady and compact rust layer. Thus the micro alloying of RE leads to raising the atmospheric corrosion resistance in high tension weathering steels.