He^+离子辐照Inconel 718合金表面形貌改变及机理研究

Surface Morphology Alteration and Mechanism Study of Inconel 718 Alloy Irradiated by He^+ Ions

研究了3种不同剂量He^+离子辐照后Inconel 718合金的形貌变化规律及其形成机理。结果表明,He^+离子辐照会在合金表面形成纳米多孔结构,其孔径会随辐照剂量的增加而增大。此外,He^+离子辐照还会破坏合金表面δ相并导致碳化物的持续溅射损耗,且这一现象会随着辐照剂量的增加而愈发严重。由于辐照过程中氦泡间微观应力■作用会引起毗邻材料断裂及氦泡合并长大,且辐照溅射作用又会导致氦泡上层薄膜的损耗甚至破裂,因而这也是He^+离子辐照Inconel 718合金表面纳米多孔结构的形成机制。

The rule and formation mechanism of surface morphology alteration in Inconel 718 alloy irradiated with three different doses were studied.The results indicate that He6+ions irradiation would produce nanopores in sample surfaces.The aperture of these nanopores increases with irradiation dose.Besides,He^+ion irradiation would break δ phases and lead to continuous sputtering of carbide in sample surface,and the increase of irradiation dose would aggravate these phenomena.The microstress δn between bubbles induces the fracture of adjacent material,and it also promotes the coalescence and growth of bubbles.Moreover,sputtering results in the rupture of bubbles.Therefore,the formation mechanism of nanopores in irradiated Inconel 718 alloy attributes to the combined effects of bubble growth and surface material sputtering.