加热温度对10CrNiCuSi钢氧化铁皮的影响

为改善10CrNiCuSi船板钢表面质量粗糙的问题,采用电阻炉开展了1100~1300 ℃高温氧化试验,利用弯曲试验评价了氧化铁皮的剥离性,并研究了不同温度下氧化铁皮的演变规律。结果表明,随着加热温度的升高,氧化速率增大,氧化层厚度明显增加。氧化铁皮主要由Fe₂O₃、Fe₃O₄、FeO和内氧化层组成,而内氧化层主要由FeNiCu、Fe₂SiO₄和FeO相组成。加热过程中Fe₂SiO₄/FeO共晶液相的产生对氧化铁皮的剥离性具有重要影响。在1100 ℃和1150 ℃条件下,内氧化层中的Fe₂SiO₄呈现颗粒状或块状弥散分布,氧化铁皮与基体之间界面平直,氧化铁皮易于剥离;在1200、1250和1300 ℃条件下,Fe₂SiO₄-FeO或Fe₂SiO₄发生熔化形成液相渗入基体和氧化铁皮中,造成界面粗糙,而锚状FeNiCu相与基体及氧化铁皮具有较好的结合力,两者的协同作用造成氧化铁皮难于剥离。因此在1100 ~1150 ℃条件下去除氧化铁皮较为合适。

Effect of heating temperature on oxide scale of 10CrNiCuSi steel

In order to improve the surface roughness of 10CrNiCuSi shipbuilding steel, the oxidation experiment at 1100-1300 ℃ under air condition was carried out in a resistance furnace. The exfoliation of the oxide scales was evaluated by bend tests. And the evolution of oxide scales at different temperature was studied. The results show that the oxidation rate and thickness of oxide layer increase with the increase of heating temperature. The scale of the tested steel is mainly composed of Fe₂O₃, Fe₃O₄, FeO and internal oxide layer, and the internal oxide layer consists of FeNiCu, Fe₂SiO₄ and FeO phases. The liquid eutectic Fe₂SiO₄/FeO products have a significant influence on the exfoliation of the oxide scales. At the conditions of 1100 ℃ and 1150 ℃, the Fe₂SiO₄ phases presented with granular or massive shape are dispersed in the internal FeO phases. The interface between the scale and the matrix is relatively straight and the scale is easily exfoliated. At the conditions of 1200, 1250 and 1300 ℃, the eutectic product of Fe₂SiO₄-FeO presents an anchor-like morphology, which is pinned to the interface of oxide scale and substrate resulting in rough bonding interface, and the anchor-like FeNiCu phases have a good bonding properties with substrate and the scale. The synergistic effects cause the oxide scale hard to exfoliate. Therefore, it is more appropriate to remove the oxide scales at 1100-1150 ℃.