Chemical synthesis of WC–Co from water-soluble precursors: The effect of carbon and cobalt additions to WC synthesis

• Published in: International journal of refractory metals & hard materials Vol. 56; pp. 69 - 75
• Main Authors: Kanerva, Ulla, Karhu, Marjaana, Lagerbom, Juha, Kronlöf, Anna, Honkanen, Mari, Turunen, Erja, Laitinen, Tarja
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.04.2016
• Subjects: Carbon; Carbon content; Cemented carbides; Cobalt; Nano-sized WC–Co synthesis; Precursors; Solid phases; Spray drying; Synthesis (chemistry); Tungsten carbide; Water soluble precursors; Spray drying; Water soluble precursors; Nano-sized WC–Co synthesis
• ISSN: 0263-4368; 2213-3917
• DOI: 10.1016/j.ijrmhm.2015.11.014

The chemical synthesis of WC–Co from water-soluble precursors and the effect of carbon content and cobalt addition were studied. Ammonium metatungstate AMT as tungsten source, glycine as a carbon source and cobalt acetate Co(C2H3O2)2 as a cobalt source was dissolved in water and spray-dried, and thermal synthesis in Ar atmosphere was performed. In order to understand the effects of carbon content and cobalt addition on synthesis steps, and the chemical and phase structure, thermogravimetry (TGA) with Differential Scanning Calorimetry (DCS) and mass spectrometry was used together with X-ray diffractometry and chemical analysis. The results reveal that carbon content mainly affected reduction temperatures and cobalt addition to reaction route and solid state synthesis temperature. This presented manufacturing route with water-soluble raw materials was a potential way of preparing nanostructural WC–Co composition with the correct phase structure and chemical composition. •Homogenous and nanostructural WC-Co was prepared with grain size varied from 50nm to 200nm.•Carbon content affects the reduction temperature of tungsten oxide to metallic tungsten.•Cobalt addition promotes the solid state synthesis of tungsten and carbon to WC.