科研之友
微信
新浪微博
Facebook
分享链接
摘要
To improve the final density of ceramic parts via indirect selective laser sintering (SLS), cold/hot isostatic pressing (CIP/HIP) technologies were introduced into the process. The proposed approach in the present study combined spray drying with mechanical mixing by which we prepared a kind of compound powder consisting of polyvinyl alcohol (PVA, 1.5 wt%), epoxy resin E06 (8 wt%), and alumina so as to get a good fluidity for SLS. At the first step, SLS parts reached the highest relative density of about 32 % when the laser energy density was 0.094 J/mm(2), which facilitated the next operation and improvement of final density. Then, a soft polymer canning was prepared for CIP around the surface of SLS alumina ceramic parts using pre-vulcanized natural rubber latex RTV-2, gelation and film. Following that, we experimented on different CIP maximum pressure which had different effects on densification of SLS alumina parts, the whole process in CIP was divided into three stages of I, II, and III. Based on thermal gravity curve of epoxy resin E06, ignoring the impacts of the only 1.5 wt% PVA on degreasing, green bodies were degreased and furnace-sintered. Finally, the relative density of alumina parts reached 95.94 % after HIP process. Field emission scanning electron microscopy was used to analyze the densification evolvement in each stage of process and the fracture mechanism. The study showed a positive and practical approach to manufacture ceramic matrix and ceramic components with complex shape by indirect SLS technology.
- 出版日期2013-8
- 单位华中科技大学
