Abstract This study investigated the feasibility of diamond crystal synthesis under high-pressure high temperature (HPHT) using the Ni-Mn-C system with 1–5 wt% of Mg at 4.5 GPa, 1250 ± 50 °C, for 180 s. The objective of using magnesium as a dopant was to evaluate its impact on crystal growing mechanisms and on the defects so as to employ the diamonds in cutting tools, once the synthetic parameter values are smaller than those found in the literature. The crystal morphology depicted a transformation from octahedral to cube-octahedral shape as Mg was weight increased. According with the results from Raman spectroscopy, full width at half maximum (FWHM), residual stress, X-ray diffraction (XRD), the high Mg crystals presented a solubility limit during the diamonds synthesis, with druses at 4 and 5 wt% of Mg and a noticeable displacement peak in XRD and Raman spectra.

中文翻译：

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Ni-Mn-C 系统中 HPHT 金刚石结晶：添加镁的影响

摘要 本研究调查了在高压高温 (HPHT) 下使用 Ni-Mn-C 系统在 4.5 GPa、1250 ± 50 °C、180 s、1-5 wt% Mg 下合成金刚石晶体的可行性。使用镁作为掺杂剂的目的是评估其对晶体生长机制和缺陷的影响，以便在合成参数值小于文献中发现的值时将金刚石用于切削工具。晶体形态描述了随着镁的重量增加，从八面体形状到立方八面体形状的转变。根据拉曼光谱、半峰全宽 (FWHM)、残余应力、X 射线衍射 (XRD) 的结果，高镁晶体在金刚石合成过程中呈现出溶解度极限，