Plasma rare earth nitriding of nanocrystallized surface layer of 3J33B steel at 350 and 410℃ for different time was studied. The microstructure observation and X-ray diffraction(XRD) analysis show that the nitriding layer consists of compound layer (γ′-Fe4N) and diffusion layer (α-Fe). Lanthanum content profiles in nanocrystallized surface layer were measured using glow discharge spectometry(GDS). The results show that lanthanum can diffuse into the surface layer of the steel to a large depth. Based on the experimental results mentioned above, the diffusion coefficients and activation energy of lanthanum in γ′ phase are calculated to be 1.03×10 -15 cm2/s (350℃), 1.75×10 -15 cm2/s (410℃) and 31.313kJ/mol, respectively.
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机译:High-precision analysis on annual variations of heavy metals, lead isotopes and rare earth elements in mangrove tree rings by inductively coupled plasma mass spectrometry