Guignard Jérémy, Prakasam Mythili, Largeteau Alain
UMR 5026, ICMCB, CNRS, Universite Bordeaux, F-33600 Pessac, France.
Materials (Basel). 2022 Mar 16;15(6):2198. doi: 10.3390/ma15062198.
Nowadays, synthetic diamonds are easy to fabricate industrially, and a wide range of methods were developed during the last century. Among them, the high-pressure-high-temperature (HP-HT) process is the most used to prepare diamond compacts for cutting or drilling applications. However, these diamond compacts contain binder, limiting their mechanical and optical properties and their substantial uses. Binderless diamond compacts were synthesized more recently, and important developments were made to optimize the P-T conditions of sintering. Resulting sintered compacts had mechanical and optical properties at least equivalent to that of natural single crystal and higher than that of binder-containing sintered compacts, offering a huge potential market. However, pressure-temperature (P-T) conditions to sinter such bodies remain too high for an industrial transfer, making this the next challenge to be accomplished. This review gives an overview of natural diamond formation and the main experimental techniques that are used to synthesize and/or sinter diamond powders and compact objects. The focus of this review is the HP-HT process, especially for the synthesis and sintering of binderless diamonds. P-T conditions of the formation and exceptional properties of such objects are discussed and compared with classic binder-diamonds objects and with natural single-crystal diamonds. Finally, the question of an industrial transfer is asked and outlooks related to this are proposed.
如今，合成钻石在工业上易于制造，并且在上个世纪开发了多种方法。其中，高温高压（HP-HT）工艺是最常用于制备用于切割或钻探应用的金刚石复合体的方法。然而，这些金刚石复合体含有粘结剂，限制了它们的机械和光学性能以及它们的大量应用。无粘结剂金刚石复合体是最近合成的，并且在优化烧结的压力-温度条件方面取得了重要进展。所得烧结复合体的机械和光学性能至少与天然单晶相当，并且高于含粘结剂的烧结复合体，具有巨大的潜在市场。然而，烧结此类物体的压力-温度（P-T）条件对于工业转化而言仍然过高，这成为下一个有待攻克的挑战。本综述概述了天然金刚石的形成以及用于合成和/或烧结金刚石粉末及致密物体的主要实验技术。本综述的重点是高温高压工艺，特别是无粘结剂金刚石的合成和烧结。讨论了此类物体形成的压力-温度条件及其优异性能，并与经典的含粘结剂金刚石物体和天然单晶金刚石进行了比较。最后，提出了工业转化的问题并给出了与之相关的展望。
