Development of adherent diamond coatings on transition-metal substrates

在过渡金属表面沉积高附着力的金刚石薄膜是等离子体辅助化学气相沉积金刚石领域最具挑战性的研究课题之一。钢合金属于这类材料，如果可以在钢上实现金刚石沉积，则可以显著改善钢的表面性能。萨斯喀彻温大学等离子体物理实验室最近发现，向钢合金中加入少量Al（铝）大大促进了高密度、粘附性金刚石薄膜的沉积。据推测，Al的3d电子负责修改合金中的电子结构，并减轻对金刚石生长不利的石墨的催化形成。加拿大光源（CLS）提供的XAS（X射线吸收光谱）将用于检测钢合金中含铝和不含铝的电子结构的变化。该研究的直接目标是阐明过渡金属上金刚石生长的机制，并找到最佳沉积条件。开发钢合金金刚石涂层技术的好处主要是表面保护和改性（耐腐蚀和耐磨性，生物相容性，改善导热性等）。最广泛使用的工业金属。

Depositing highly adherent diamond thin films on transition metals has been one of the most challenging research subjects in the area of diamond synthesis based on plasma assisted chemical vapor deposition. Steel alloys belong to this category of materials and if diamond deposition on steels can be achieved, the surface properties of steels can be improved dramatically. In the Plasma Physics Laboratory, University of Saskatchewan, it has recently been found that adding a small amount of Al (aluminum) to steels alloys greatly facilitates deposition of high density, adherent diamond thin films. It is speculated that 3d electron of Al is responsible for modifying the electronic structure in the alloy and mitigating the catalytic formation of graphite which is detrimental to diamond growth. XAS (x-ray absorption spectroscopy) available at the Canadian Light Source (CLS) will be used to detect changes in electronic structures with and without Al in steel alloys. The immediate objective of the proposed research is to clarify the mechanism of diamond growth on transition metals and find optimum deposition conditions. The benefit of developing a technology for diamond coating on steel alloys is mainly in surface protection and modification (corrosion and wear resistance, biocompatibility, improved thermal conductivity, etc.) of the most widely used industrial metal.