成形剂对碳化硼压坯密度和烧结密度的影响
来源期刊：中南大学学报(自然科学版)2002年第4期
论文作者：王零森 尹邦跃 方寅初
文章页码：377 - 379
关键词：关键词:碳化硼;压制;成形剂;烧结;活化剂
Key words：boron carbide; pressing; pressing additive; sintering; activator
摘 要：研究了葡萄糖、酚醛树脂、硬脂酸以及酚醛树脂加硬脂酸这4种成形剂的加入量和成形压力对碳化硼压坯密度的影响,探讨了碳化硼压坯密度和烧结密度的关系.研究结果表明:加入葡萄糖所得到的碳化硼压坯密度最高;碳化硼烧结密度随压坯密度的增加呈正比例增加;颗粒间接触面积增加有利于扩散,但当压坯密度为1.87 g/cm3时(对于粉末4),这种线性关系的斜率明显变小,说明压制压力不需过大;所选用的成形剂在烧结过程中分解成碳并残留在压坯中,这些新生态的碳对烧结起活化添加剂的作用.因此,加入这些成形剂既提高了碳化硼压坯密度,又导致其烧结密度增加.
Abstract: Taking glucose, phenolic resin, stearic acid and the mixture of phenolic resin and stearic acid as pressing additives, the influence of these additives and the compaction pressure on the green density of boron carbide are studied.The experiments indicate that the glucose is much better than the others, and the green density obtained using glucose is the highest. The sintered densities have a direct proportion to green densities, because this is a single phase solid system sintering process, and the higher, the green density, the bigger the contact area of the particles, which is beneficial to the diffusion in sintering process. When the green density is greater than 1.87 g/cm3, the sintered density increases slowly with the increases of green density, though the linear relationship remains. It means that high pressure is not of benefit to increase sintered density.
