Synthesis of Ultrafine Particles of Nanosize Reinforced Composites

本项目研究了燃烧合成和湿法化学合成制备纳米级原位增强复合材料超细合金颗粒的方法。重点将放在Ti/TiB2复合材料的生产上，尽管所采用的工艺适用于广泛的金属间化合物。燃烧合成的方法是将Na与TiCl4和BCI3反应生成Ti/TiB2合金。将建造一个流动反应器，以模拟生产规模系统中的过程，但也允许对颗粒形成进行详细调查，生长和冷却过程。测量将通过探针取样和光散射技术的结合来进行。湿化学方法将是使用金属有机前体和中间体的低温液相技术。反胶束和聚合物稳定剂将用于控制纳米晶体的合成、尺寸和稳定性。通过上述两种工艺所产生的纳米级颗粒的固结所获得的材料的微观结构稳定性和力学性能也将被研究。​在合成这些合金的过程中，人们期望一种新型材料具有高强度、高弹性模量、高韧性和冲击性能、对温度变化或热冲击的低敏感性。表面耐久性高，对缺陷的敏感性低。

This project investigates the combustion synthesis and wet-chemical synthesis methods for producing ultrafine alloy particles in the form of nanosize reinforced in situ composites. Emphasis will be given to the production of Ti/TiB2 composites, although the processes employed are applicable to a wide range of intermetallics. The methodology for combustion synthesis involves reacting Na with TiCl4 and BCI3 to produce a Ti/TiB2 alloy. A flow reactor will be constructed which simulate the processes that would occur in a production-scale system, but also allow for a detailed investigation of the particle formation, growth and cooling processes. Measurements will be performed by a combination of probe sampling and light scattering techniques. The wet-chemical approach will be a low- temperature, solution-phase technique using metalorganic precursors and intermediates. Inverse micelles and polymeric stabilizers will be used to control the syntheses, sizes, and stabilities of the nanocrystals. The microstructural stability and mechanical properties of the materials obtained by consolidation of the nanosize particles produced by the two processes outlined above will be also studied. In synthesizing these alloys a new class of materials is expected that will exhibit high strength, high elastic modulus, high toughness and impact properties, low sensitivity to temperature chance or thermal shock, high surface durability and low sensitivity to flaws.