Microstructure and growth mechanism of tungsten carbide coatings by atmospheric CVD

Huicong Zhang, Xiaodong Yu, Zhihua Nie, Chengwen Tan*, Fuchi Wang, Huaijian Cai, Ying Li, Fang Wang, Hongnian Cai

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

20 Citations (Scopus)

Abstract

A tungsten carbide coating was prepared by atmospheric chemical vapor deposition (CVD) with tungsten hexafluoride (WF6), hydrogen, and dimethyl ether (DME) as the reaction gases, under a dimethyl ether partial pressure (PDME) of 3.2–21.0 kPa and a temperature of 550–600 °C. The phase compositions of the coatings are W2C + W and W3C + W, and it is found that when PDME is low, the coating has a lamellar structure, but at a high PDME, the lamellar structure and fibrous tissue are simultaneously present in the scanning electron microscope (SEM) image. In the latter case, no delamination was found, which was visible at a low PDME. In addition, as the PDME increases, the deposition rate of the coating decreases, and ultimately, the coating cannot continue to grow. The growth model of the tungsten carbide coating based on the kinetics of the chemical vapor deposition of tungsten by the hydrogen reduction of tungsten hexafluoride was proposed, and the influences of PDME and temperature on the coatings were discussed and the orientation relationship between W and W2C in high resolution transmission electron microscopy (HRTEM) was analyzed.

Original languageEnglish
Pages (from-to)85-92
Number of pages8
JournalSurface and Coatings Technology
Volume344
DOIs
Publication statusPublished - 25 Jun 2018
Externally publishedYes

Keywords

  • Chemical vapor deposition (CVD)
  • Coating
  • Fibrous tissue
  • Lamellar structure
  • Phase composition
  • Tungsten carbide

Fingerprint

Dive into the research topics of 'Microstructure and growth mechanism of tungsten carbide coatings by atmospheric CVD'. Together they form a unique fingerprint.

Cite this