410不锈钢在550℃流动的铅铋共晶合金中的腐蚀行为

Corrosion Behavior of Stainless Steel 410 in Flowing Lead-Bismuth Eutectic Alloy at 550 ℃

为了研究马氏体410不锈钢在不同流速的高温液态铅铋共晶合金中的腐蚀行为,本工作对410不锈钢在相对流速为0 m/s、1.70 m/s、2.31 m/s、2.98 m/s的550℃液态铅铋共晶合金中进行600 h试验后的腐蚀现象进行研究,并对不同流速腐蚀试验后的腐蚀试样的表面和截面分别进行XRD、SEM、EDS检测。结果发现:随着相对流速的增大,腐蚀样品表面的氧化层越来越致密,氧化层的厚度也不断增厚。这是由于传质速率的增大加快了氧化层的生成速率;腐蚀样品表面的氧化层主要分为外氧化层和内氧化层,外氧化层主要由Fe3O4以及部分渗入的Pb-Bi组成,内氧化层主要为尖晶石结构的(Fe,Cr)3O4;在腐蚀过程中同时发生晶间腐蚀和氧化腐蚀现象。

In order to study the corrosion behavior of martensitic stainless steel 410 in lead-bismuth eutectic alloy(LBE)at high temperature with different relative velocities,the article investigated the corrosion phenomena of stainless steel 410 in lead-bismuth eutectic alloy at 550℃for 600 h with relative velocities of 0 m/s,1.70 m/s,2.31 m/s and 2.98 m/s.X-ray diffraction(XRD),scanning electron microscopes(SEM)and energy dispersive spectrometry(EDS)were carried out on the surface and cross-section of corrosive samples with different relative velocities.The results indicate that the oxide layer becomes denser and thicker on the surface of corrosion samples with the increase of relative flow rate,due to the increase of mass transfer rate accelerates the formation rate of oxide layer.The oxide layer on the surface of corrosion samples can be divi-ded into outer oxide layer and inner oxide layer.The outer oxide layer is mainly composed of Fe 3O 4 and partially infiltrated Pb-Bi and the inner oxide layer is mainly spinel(Fe,Cr)3O 4.Intergranular-corrosion and oxidation-corrosion occurred simultaneously during the corrosion process.