Kwon Young Jin, Casati Riccardo, Coduri Mauro, Vedani Maurizio, Lee Chong Soo
Graduate Institute of Ferrous Technology (GIFT), Pohang University of Science and Technology (POSTECH), Pohang 790-784, Korea.
Technical Research Laboratories, POSCO, Pohang 790-785, Korea.
Materials (Basel). 2019 Jul 25;12(15):2360. doi: 10.3390/ma12152360.
A study was performed to investigate the hydrogen embrittlement behavior of 18-Ni 300 maraging steel produced by selective laser melting and subjected to different heat treatment strategies. Hydrogen was pre-charged into the tensile samples by an electro-chemical method at the constant current density of 1 A m and 50 A m for 48 h at room temperature. Charged and uncharged specimens were subjected to tensile tests and the hydrogen concentration was eventually analysed using quadrupole mass spectroscopy. After tensile tests, uncharged maraging samples showed fracture surfaces with dimples. Conversely, in H-charged alloys, quasi-cleavage mode fractures occurred. A lower concentration of trapped hydrogen atoms and higher elongation at fracture were measured in the H-charged samples that were subjected to solution treatment prior to hydrogen charging, compared to the as-built counterparts. Isothermal aging treatment performed at 460 °C for 8 h before hydrogen charging increased the concentration of trapped hydrogen, giving rise to higher hydrogen embrittlement susceptibility.
进行了一项研究，以调查通过选择性激光熔化生产并经过不同热处理策略的18-Ni 300马氏体时效钢的氢脆行为。在室温下，通过电化学方法以1 A/m和50 A/m的恒定电流密度将氢预充入拉伸样品中48小时。对充氢和未充氢的试样进行拉伸试验，最终使用四极质谱分析氢浓度。拉伸试验后，未充氢的马氏体时效样品的断口呈现出韧窝。相反，在充氢合金中，发生了准解理模式断裂。与原始状态的样品相比，在充氢前经过固溶处理的充氢样品中，捕获的氢原子浓度较低，断裂伸长率较高。在充氢前于460°C等温时效处理8小时会增加捕获的氢浓度，从而导致更高的氢脆敏感性。
