1. Densification of SiO2–cBN composites by using Ni nanoparticle and SiO2 nanolayer coated cBN powder
- Author
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Zhang, Jianfeng, Tu, Rong, and Goto, Takashi
- Subjects
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SILICON oxide , *NANOPARTICLES , *METAL coating , *METAL powders , *BORON nitride , *SINTERING , *PHASE transitions , *METAL hardness - Abstract
Abstract: Cubic boron nitride (cBN) powder was coated with Ni nanoparticle and SiO2 nanolayer (abbreviated as cBN/Ni and cBN/SiO2, respectively) by rotary chemical vapor deposition (RCVD), and compacted with SiO2 powder by spark plasma sintering at 1473–1973K for 0.6ks. The effects of Ni and SiO2 coatings on the densification, phase transformation of cBN and hardness of SiO2–cBN composites were compared. The phase transformation of cBN to hBN was identified at 1973K in SiO2–cBN/SiO2 composites, 300K higher than that in SiO2–cBN/Ni composites, indicating that SiO2 retarded the transformation of cBN. The relative density of SiO2–cBN/SiO2 with 50vol% cBN sintered at 1873K was 99% with a hardness of 14.5GPa. [Copyright &y& Elsevier]
- Published
- 2012
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