快速凝固Mg-5Zn-1Y-0.6Zr合金腐蚀性能的研究

摘要

研究了快速凝固Mg-5Zn-1Y-0.6Zr合金在3.5%NaCl溶液中的腐蚀行为.利用金相显微镜、SEM观察了合金的微观组织和腐蚀形貌.结果表明,快速凝固使合金产生非晶相、晶粒细化及微观组织均匀,均对耐腐蚀性能提高起到作用.在室温下,腐蚀速率随时间先增大,随后逐渐减小.XRD分析表明腐蚀后的主要产物是Mg(OH)_2.通过极化曲线测试,表明合金耐蚀性能随冷却速率的提高而改善.%The effects of rapidly solidification on the microstructure and the corrosion behavior of Mg-5Zn-1Y-0.6Zr alloys in the 3.5% NaCl solution were investigated. The microstructure and the corrosion surface of the alloy were observed using OM and SEM. The results show that the amorphous phase occurred and alloy microstructures are refined and more uniformed by rapidly solidification,then the corrosion resistance of the alloy is improved. At room temperature, the corrosion rate increased firstly and then reduced with increase of time. The main corrosive product was mainly Mg(OH)_2 using XRD. Polarization curve test result shows the corrosion resistance is better as the cooling rate is higher.