Volume 38, Issue 4 (Journal of Advanced Materials-Winter 2020)                   jame 2020, 38(4): 75-85 | Back to browse issues page


XML Persian Abstract Print


Download citation:
BibTeX | RIS | EndNote | Medlars | ProCite | Reference Manager | RefWorks
Send citation to:

Shirvani M, Mashhadi M, Yosofi M. Synthesis of HfB2 Powders by Carbothermal Reduction. jame. 2020; 38 (4) :75-85
URL: http://jame.iut.ac.ir/article-1-1014-en.html
2. Department of Composite Materials Engineering, Malek Ashtar University of Technology, Tehran, Iran. , me_mashadi@yahoo.com
Abstract:   (3060 Views)
In this research, solid state carbothermal synthesis of HfB2 Nano powders was investigated. For this purpose, HfO2,H3BO3, carbon active or phenolic resin were used as raw materials for carbothermal reaction. After 2-4 hours of milling the raw materials by a planetary ball in an ethanol media, the mixture was heat dried and pressed in to disks under pressure of 20-30 bar. The disks were then placed in a graphite crucible and heat-treated at 1500–1600 °C for 1 hour under flowing Ar atmosphere. The powder product was analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and backscattered electron (BSE) imaging. The heat treatment temperature, amount of boric acid, milling and heat treatment time were recognized as four factors influencing synthesis and size of HfB2 powder particles. SEM images reported irregular morphologies with a particle size of about 2-4 µm for HfB2 powder. The best sample was obtained at a molar ratio of HfO2 : phenolic resin carbon: boric acid = 1:5:5 at 1600 °C after 1 hour of heat treatment. XRD results confirmed synthesis of pure HfB2 with a crystallite size of about 60 nm.
Full-Text [PDF 873 kb]   (465 Downloads)    
Type of Study: Research | Subject: Nanomaterials
Received: 2018/12/26 | Accepted: 2019/12/14 | Published: 2020/02/10

Add your comments about this article : Your username or Email:
CAPTCHA

Send email to the article author


Rights and permissions
Creative Commons License This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

© 2021 CC BY-NC 4.0 | Journal of Advanced Materials in Engineering (Esteghlal)

Designed & Developed by : Yektaweb