Coating Process of iron siliside on iron for oxidation resistance

铁上硅化铁的抗氧化涂层工艺

• 批准号: 10555256
• 负责人: SUZUKI Ryosuke
• 金额: $ 5.89万
• 依托单位: KYOTO UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B).
• 财政年份: 1998
• 资助国家: 日本
• 起止时间: 1998 至 2000
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-10555256/
• 关键词: iron silicide; oxidation resistance; molten salt; surface treatment; high temperature oxidation; steel sheet; concentration gradience; silicon; 耐酸化性被膜; オゾン酸化; 高温X線回折

A process to coat Fe_3Si-SiO_2 composite film on the mild steel was developed for corrosion and oxidation resistance. Using the molten salt, the iron silicide was deposited on the iron sheet, and its surface was then oxidized by ozone gas at the low temperature.The molten salt consisting of KCl-NaCl-NaF-Si-SiO_2-Na_2SiF_6 was chosen because of the minimized evaporation and oxidation, and stability in air. Electroless coating on the pure iron and on the mild steel formed the smooth Fe_3Si layer over 100μm thick within 1 hour. The molten salt was trapped at the interface between silicide layer and the substrate when the growth was so rapid. No defect was fund when the iron-silicon alloy was supplied as the substrate. These findings showed that such a rapid supply of silicon ions from pure silicon to the molten salt caused the defects. The coating mechanism consisted of disproportional reaction and diffusion. Considering the growth mechanism, the α-(iron, silicon) alloy was successfully coated on iron and the layer did not contain any defects, when the aluminum-silicon liquid alloy was used instead of pure silicon. Subsequently the molten salt was replaced to the conventional salt containing pure silicon. The layer had the concentration gradient in the layer and no defects at the interface. The healthy coating was achieved by alloying silicon to control activity, or by reducing silicon ion concentration in the salt.Similarly, the silicide layer for oxidation resistance was formed on the refractory metals such as molybdenum, niobium and nickel. A new finding was that ozone gas blowing could form Cr_2O_3 layer by producing the molten CrO_3.

研究了一种在低碳钢表面制备Fe 3SiSiO 2复合膜的工艺。采用熔盐法在铁板上沉积硅化铁，然后在低温下用臭氧气体对其表面进行氧化，选择KCl-NaCl-NaF-Si-SiO_2-Na_2SiF_6组成的熔盐，其蒸发和氧化最小，在空气中稳定。在纯铁和低碳钢表面化学镀1h内可形成100μm厚的平整的Fe_3Si层。当硅化物层生长过快时，熔盐被捕获在硅化物层与衬底的界面处。以铁硅合金为基体，无缺陷。这些发现表明，硅离子从纯硅到熔融盐的快速供应导致了缺陷。包覆机理包括不均衡反应和扩散。从生长机理上考虑，用铝硅合金液代替纯硅，在铁基体上成功地制备了α-（铁，硅）合金涂层，且涂层无缺陷。随后将熔融盐替换为含有纯硅的常规盐。该层在层内具有浓度梯度，在界面处没有缺陷。健康的涂层是通过合金化硅来控制活性，或通过降低盐中的硅离子浓度来实现的。类似地，在难熔金属如钼、铌和镍上形成抗氧化的硅化物层。新的发现是臭氧吹扫可以通过产生熔融CrO_3而形成Cr_2O_3层。

项目成果

R.O.Suzuki: "Electroless Coating of Fe_3Si on Steels in the Moleten Salt"Proc.of 6th Intern.Conf.on Molten Slags, Fluxes and Salts. 22_360.1-16 (2000)

R.O.Suzuki：“铁盐中钢上 Fe_3Si 的化学镀”Proc.of 6th Intern.Conf.on Molten Slags, Fluxes and Salts。

R.O.Suzuki: "Electroless Coating of Fe_3Si on Steel in the Molten Salt"steel research. 71. 130-137 (2000)

R.O.Suzuki：“钢上熔盐中 Fe_3Si 的化学镀层”钢研究。

R.O.Suzuki: "Growth of Fe_3Si Layer Deposited from the Molten Salt"steel research. 71. 138-143 (2000)

R.O.Suzuki：“从熔盐沉积的 Fe_3Si 层的生长”钢研究。

R.O.Suzuki: "MoSi_2 Coating on Molybdenum Using Molten Salt"J.Alloys and Compounds. 306. 285-291 (2000)

R.O.Suzuki：“使用熔盐在钼上进行 MoSi_2 涂层”J.合金和化合物。

R.O.Suzuki: "Electroless Coating of Fe_3Si on Steels in the Moleten Salt"Proc.of 6th Intern.Conf.on Molten Slags,Fluxes and Salts. 180.1-180.16 (2000)

R.O.Suzuki：“铁盐中钢上 Fe_3Si 的化学镀”Proc.of 6th Intern.Conf.on Molten Slags, Fluxes and Salts。