高温高压快速制备高导热PcBN陶瓷

Rapid Preparation of High Thermal Conductivity PcBN Ceramics by High Temperature and High Pressure Method

高导热聚晶立方氮化硼(PcBN)是制备散热基板的理想陶瓷材料,但是常规烧结方法难以制备出高致密度的PcBN陶瓷。本文以Al-Si为结合剂,采用高温高压快速制备PcBN陶瓷复合材料,并研究不同Al-Si比例对PcBN陶瓷热导率的影响。研究发现,少量Si的加入有利于PcBN致密度的提高,随着Si含量的增加,立方氮化硼烧结体的热导率先增加后下降。Al-Si比例为7∶3时的PcBN的热导率最高,达到88.01 W/m·K,比纯Al结合剂的PcBN陶瓷提升了12.33%。

Polycrystalline cubic boron nitride(PcBN)with high thermal conductivity is an ideal ceramic material for heat dissipation substrate,but PcBN with high density is difficult to prepare by conventional sintering method.By using high temperature and high pressure sintering method,PcBN ceramic composites with Al-Si binder were rapidly prepared.The effect of the Al-Si ratio on thermal conductivity of PcBN ceramics was studied.It is found that the addition of a small amount of Si is beneficial to density increase of PcBN.While the thermal conductivity of PcBN will first increase and then decrease with the increase of Si content.The maximum thermal conductivity of PcBN ceramics is 88.01 W/m·K with Al-Si ratio of 7∶3,which is 12.33%higher than those of PcBN ceramics with pure Al bonder.