Heavy-ion irradiation has been widely used to simulate neutrons-irradiation induced damage effects, due to its higher damage rate and lower activation of the post-irradiation manipulation. The high-energy ion beam is capable of producing a thickness of dozens of microns damaged region in steel, making it possible to evaluate the macroscopic mechanical properties of the irradiated specimens. In the present paper, a method to quantify the constitutive relationships of high-energy heavy-ion irradiated steels is proposed. Ni²²⁺ ions with a kinetic energy of 357.86 MeV provided by a cyclotron were used to produce a quasi-homogeneous atomic displacement damaged layer (about 25 μm in thickness) in specimens of 316 L stainless steel. The temperature of the specimens were kept at about −50 °C during ion irradiation. Two damage levels of 0.16 and 0.33 displacement per atom (dpa) were approached. Small punch test of the unirradiated and irradiated ϕ3 mm disk samples was carried out to obtain the load-deflection curves. A series of finite element simulation of SPT of the laminated irradiated samples, in combination with sequential programming algorithm, was performed to characterize the constitutive relationships of the irradiation damaged layer of the samples. Finite element simulations with obtained constitutive relationships show agreement with the experimental results. Nanoindentation tests were carried out to verify the identified constitutive relationships. The nanoindentation results show an irradiation induced hardening in good agreement with that from the obtained constitutive relationships.

重离子辐照由于其更高的损伤率和辐照后操纵的较低活化，已被广泛用于模拟中子辐照引起的损伤效应。高能离子束能够在钢中产生数十微米厚的损坏区域，从而可以评估被辐照样品的宏观机械性能。本文提出了一种量化高能重离子辐照钢本构关系的方法。镍²²⁺由回旋加速器提供的动能为357.86 MeV的离子用于在316 L不锈钢样品中产生准均质的原子位移破坏层（厚度约25μm）。在离子辐射期间，样品的温度保持在约-50℃。接近两个损伤水平，每个原子位移0.16和0.33（dpa）。对未辐照和辐照的小打孔测试ϕ进行3mm的盘样品以获得载荷-挠曲曲线。结合顺序编程算法，对层压辐照样品的SPT进行了一系列有限元模拟，以表征样品辐照损伤层的本构关系。具有获得的本构关系的有限元模拟表明与实验结果一致。进行了纳米压痕测试以验证所识别的本构关系。纳米压痕结果表明辐射诱导的硬化与从获得的本构关系得到的一致。