Inconel 718高温合金耐腐蚀表面层制备

Manufacturing of Anti-Corrosive Surface Layer of Inconel 718 Superalloy

微锻是一种通过微锻头对基体表面进行机械冲击,从而实现表面强化的工艺。针对深海海底条件下高温合金腐蚀失效的问题,提出一种基于微锻机械冲击作用的表面层制备工艺,实现Inconel 718高温合金防腐表面层的制备。实验结果表明,通过微锻制备的Inconel 718防腐表面层致密性好、孔隙较少且具有更小的晶粒尺寸,防腐性能相比基体至少提升了一个数量级;随着表面层厚度的增加和激光后处理的引入,微锻表面层的防腐性能呈现上升趋势。并解释了表面层增强Inconel 718高温合金耐腐蚀性能的机理是优异的阻隔效应和晶界的减少。相比传统防腐涂层,微锻表面层可以有效防止涂层脱落,因此有着更好的结合强度和稳定性。该工艺方案为采用微锻技术提升深海海底油气开采设备服役寿命提供了理论基础。

Microforging is a process that involves mechanical impact on the surface of a substrate using microforging heads to achieve surface strengthening.In response to the issue of corrosion failure of superalloys under deep-sea seabed conditions,a surface layer preparation technique based on the action of microforging mechanical impact is proposed to fabricate an anti-corrosive surface layer for Inconel 718 superalloy.Experimental results demonstrate that the Inconel 718 anti-corrosive surface layer prepared by microforging exhibits good density,fewer pores,and smaller grain size compared to the substrate,with the anti-corrosion performance being at least one order of magnitude higher than that of the substrate.With the increase of surface layer thickness and the introduction of laser post-treatment,the anti-corrosion performance of the microforged surface layer shows an increasing trend.The mechanism behind the enhancement of c anticorrosion performance of Inconel 718 superalloy by the surface layer is attributed to the excellent barrier effect and reduction of grain boundaries.Compared to the traditional anti-corrosive coatings,the microforged surface layer effectively prevents coating detachment,thus exhibiting better bonding strength and stability.A theoretical basis is provided for enhancing the service life of deep-sea oil and gas extraction equipment using microforging technology.