人造金刚石合成中黑色低磁金刚石的研究

 通过对合成金刚石的原材料和合成产物——石墨、Ni₇₀Mn₂₅Co₅触媒、普通人造金刚石、黑色人造金刚石、NiMnCoC熔体的磁化率测试，以及对黑色人造金刚石和普通人造金刚石破碎断面扫描电镜的对比分析，认为黑色人造金刚石形成低磁性的原因是由于合成过程中温度偏高、压力偏低，生长的金刚石质量差、裂纹多。晶体内夹杂了很多石墨与触媒包裹体，同时金刚石表面与金刚石晶体内的触媒包裹体之间形成贯穿性的裂纹。在金刚石化学提纯处理过程中，金刚石晶体内的铁磁性触媒包裹体杂质被通过裂纹进入的酸除去。因而在检测金刚石磁性时，黑色金刚石的磁性很小，呈弱磁性。

Study on the Synthesized Black Low-Magnetism Diamond

Based on the testing of the magnetic susceptibility of the raw materials and the final products:graphite,Ni_(70)Mn_(25)Co_5,general diamond,black diamond and melting NiMnCoC in the synthesis of diamond and the analyzing of the fracture surface of black diamond and general diamond by the Scanning Electron Microscope,it is found that the magnetism of the synthetic diamond is caused by(NiMnCoC) inclusions.There are many inclusions in the fracture surface of general diamond,but there are no inclusions in the fracture surface of black diamond,merely many cavities existed.The low magnetism existing in black diamond is from the poor quality and more-cracked diamond caused by higher temperature and lower pressure in the synthesis of diamond.A lot of cracks exit between diamond surface and inclusion.Because the magnetic catalyst inclusions are removed by acids through the cracks during the process of chemical treatment,the black diamond has low magnetism.