J4节镍奥氏体不锈钢热轧钢带氧化皮显微结构分析

Microstructure Analysis of Oxide Scale of Nickel-efficient Austenitic Stainless Steel J4 Hot Rolled Strip

应用XRD、SEM技术对J4节镍奥氏体不锈钢热轧钢带氧化皮的显微结构进行了分析。结果表明:J4节镍奥氏体不锈钢热轧钢带氧化皮出现局部脱落现象,未脱落部分开裂,为疏松易脱落结构。氧化皮厚度分布不均,但总体较厚,最厚达到45μm。氧化皮主要由外层赤铁矿结构的Fe(Mn)_2O_3以及内层尖晶石结构的Fe(Cr,Mn,Si)_3O_4组成,而形成这种结构主要是由于Fe迁移速率较高,而Cr迁移速率较慢。

The microstructure of oxide scale of J4 nickel-efficient austenitic stainless hot rolled strip was analyzed by SEM and XRD. The results show that local shedding of the oxide scale qppears, the partof oxide scale which doesn＇t fall off crack. The oxide scale is loose and easy to fall off. The thickness distribution of oxide scale is uneven, the overall thickness is big and the biggest thickness is 45 μm.The oxide scale is mainly composed of the outer hematite structure of Fe （Mn）203 and the inner spinel structure of Fe （Cr, Mn, Si）304. The formation of the structure is mainly due to the high migration rate of Fe and the low migration rate of Cr.