Preparation of multi-phase composite of tungsten carbide, tungsten boride and carbon by arc plasma melting: characterization of melt-cast product. Issue 1 (January 2016)

• Record Type: Journal Article
• Authors: Dash, T.; Nayak, B.B.
• Is Part Of: Ceramics international. Volume 42:Issue 1:Part A(2016)
• Page Start: 445
• Page End: 459
• Publication Date: 2016-01
• Subjects: Arc plasma -- Tungsten carbide -- Boron carbide -- Tungsten boride; Ceramics -- Periodicals; Céramique industrielle -- Périodiques; Ceramics; Periodicals; Electronic journals; 666
• DOI: 10.1016/j.ceramint.2015.08.129
• Languages: English
• ISSNs: 0272-8842

Abstract

Abstract: Arc plasma melting of WC+B4 C followed by an in situ furnace cooling produced a multi-phase composite consisting of tungsten carbide, tungsten boride and carbon. The melt-cast product was prepared in six different compositions by varying the boron carbide content (within 1–15 wt%) at the charge stage. XRD, SAED and XPS characterizations of the product showed the major phases to constitute of W2 B, WB, W2 B5 (WB2 ), WC, W2 C and C. Carbon was found to exist in three different forms, such as graphite, diamond / DLC and nanocrystalline diamond (C–C sp 3 coordination). FESEM, TEM and BET studies revealed the surface morphology, microstructure and non-porous nature of the composites respectively. From micro Raman spectra it was evident that W2 C and all tungsten boride phases were non-Raman active with 514 nm radiation (Ar + laser). Preliminary mechanical characterization of the polished composite samples (in solid forms) showed the hardness to increase with increase in B4 C content (range: 1–10 wt%). An extraordinary hardness of 3835±80 VHN with corresponding Young's modulus of 695±33 GPa was observed for the typical composition of WC+10 wt% B4 C. However, the hardness showed decreased value for 15 wt% B4 C added sample.