高温扩散对0Cr18Ni10Ti热浸镀铝抗高温氧化性能的影响研究

Study on Effect of High Temperature Diffusion on Oxidation Resistance of 0Cr18Ni10Ti Hot Dipping Aluminum

采用熔剂法对0Cr18Ni10Ti热浸镀铝。通过高温热重分析仪对热浸镀铝试样、热浸镀铝经扩散退火处理后的试样及0Cr18Ni10Ti不锈钢试样900℃×24h短期氧化行为进行了研究,采用EDS、SEM对截面进行了能谱分析及形貌观察,利用XRD对表面进行了物相分析。研究结果表明,热浸镀铝经950℃×2 h高温扩散试样及不锈钢900℃×24 h氧化动力学曲线均符合抛物线规律,热浸镀铝经950℃×2 h高温扩散提高了0Cr18Ni10Ti不锈钢的抗高温氧化性,Fe Al金属间化合物具有较好的抗高温氧化性能。热浸镀铝未经950℃×2h高温扩散,试样表层富铝层较疏松。

0Cr18Ni10Ti stainless steel was coated by hot-dipping in a molten aluminum bath. The high temperature oxidation behaviors of hot-dipped aluminized steel,hot-dipped aluminized steel with diffusion at 950 ℃ for 2 h and0Cr18Ni10 Ti steel were tested at 900 ℃ for 24 h using thermo gravimetric analyzer. The morphology and element distribution of the cross-section samples were studied by EDS and SEM. The phase composition of the oxidation scales was characterized by XRD. The results of high temperature oxidation test show that oxidation kinetic of the hot-dipped aluminized steel after high temperature diffusion and 0Cr18Ni10 Ti steel basically accordes to parabolic rate laws at 900 ℃ for 2 h. The high temperature oxidation resistance of 0Cr18Ni10 Ti stainless steel is increased by hot dipping aluminum and diffusion at 950 ℃for 24 h. Fe Al layer which is formed on hot dipping aluminum after high temperature diffusion has good oxidation resistance.The Al layer which is formed on hot dipping aluminum without high temperature diffusion is loose.