Abstract

Experimental studies of the effect of preliminary laser pulsed surface treatment on the mechanical properties of the diffusion welding joints of Fe–Ni alloy were carried out. The alloy surfaces was treated in an inert gas (Ar) environment by a scanning beam of nanosecond laser pulses with a wavelength of 355 nm, repetition rate of 100 Hz, and scanning speed of 1 mm/s. The laser spot was 220 μm; the energy density was 2 and 3 J/cm². The treated samples as well as the control untreated ones were placed in the same container and were diffusion bonded by hot isostatic pressing (HIP) at the temperatures of 1000 and 1160°С. The ultimate strength and elongation of weld joint materials were determined by tensile testing. It is shown that laser pulse treatment leads to improvement in both the ultimate strength and the relative elongation of the weld joints. The mechanical properties of the weld joints depend on the laser energy density. The weld joint properties can be increased by optimization of the laser treatment parameters. The best results were achieved at a laser energy density of 2 J/cm². The ultimate strength was increased by 12% and 29% for HIP temperatures of 1160 and 1000°С respectively. The elongation values also increased from 42% for untreated samples to 51% for samples treated at the energy density of 2 J/cm². Preliminary laser treatment of welded surfaces makes it possible to reduce the HIP temperature by 160°С and thereby reduce the power consumption during the HIP process.

中文翻译：

---

初步激光表面处理对Fe-Ni合金扩散焊接头力学性能的影响

摘要

进行了初步激光脉冲表面处理对 Fe-Ni 合金扩散焊接接头力学性能影响的实验研究。在惰性气体（Ar）环境中，通过波长为 355 nm、重复频率为 100 Hz、扫描速度为 1 mm/s 的纳秒激光脉冲扫描束对合金表面进行处理。激光光斑为 220 μm；能量密度为 2 和 3 J/cm ². 将处理过的样品和未处理的对照样品放在同一容器中，并在 1000 和 1160°C 的温度下通过热等静压 (HIP) 进行扩散粘合。焊接接头材料的极限强度和伸长率通过拉伸试验确定。结果表明，激光脉冲处理可提高焊接接头的极限强度和相对伸长率。焊接接头的机械性能取决于激光能量密度。可以通过优化激光处理参数来提高焊接接头性能。在 2 J/cm ²的激光能量密度下获得最佳结果. HIP 温度为 1160 和 1000°С时，极限强度分别增加了 12% 和 29%。伸长率值也从未处理样品的 42% 增加到以 2 J/cm ²能量密度处理的样品的 51% 。焊接表面的初步激光处理可以将 HIP 温度降低 160°С，从而降低 HIP 过程中的功耗。