%0 Journal Article
%T Effect of Silicon Addition on High-Temperature Solid Particle Erosion-Wear Behaviour of Mullite-SiC Composite Refractories Prepared by Nitriding Reactive
%A Xiaochao Li
%A Shusen Chen
%A Zhaohui Huang
%A Minghao Fang
%A Yan¡¯gai Liu
%A Xiaowen Wu
%A Juntong Huang
%A Baolin Liu
%J Advances in Materials Science and Engineering
%D 2014
%I Hindawi Publishing Corporation
%R 10.1155/2014/943542
%X Solid particle erosion-wear experiments on as-prepared mullite-SiC composite refractories by nitriding reactive sintering were performed at elevated temperatures, using sharp black SiC abrasive particles at an impact speed of 50£¿m/s and the impact angle of 90¡ã in the air atmosphere. The effects of silicon powder addition and erosion temperature on the erosion-wear resistance of mullite-SiC composite refractories were studied. The test results reveal that Si powders caused nitriding reaction to form ¦Â-sialon whiskers in the matrix of mullite-SiC composite refractories. The erosion-wear resistance of mullite-SiC composite refractories was improved with the increase of silicon powder addition and erosion temperature, and the minimum volume erosion rate was under the condition of 12% silicon added and a temperature of 1400¡ãC. The major erosion-wear mechanisms of mullite-SiC composite refractories were brittle erosion at the erosion temperature from room temperature to 1000¡ãC and then plastic deformation from 1200¡ãC to 1400¡ãC. 1. Introduction With the development of technology of circulating fluidized bed boiler, garbage incineration boiler, and coke dry quench there is a growing demand for high-temperature erosion-wear-resistant materials with better performances whereas the conventional wear-resistant materials cannot fully meet these requirements anymore. For instance, the refractory linings materials for circulating fluidized bed boiler are commonly eroded between 850¡ãC and 1100¡ãC by the coal powders, high-melting mineral impurity particles, and limestone grits for desulfurizing; their services can be severely shortened by such high-temperature erosion-wear [1, 2]. At present, the commonly used wear-resistant refractories mainly include the traditional mullite-SiC [3], SiC bricks, and Si3N4/sialon bonded SiC [4]. The traditional mullite-SiC bricks cannot meet the serve in high temperature due to their low erosion-wear resistance. SiC bricks and Si3N4/sialon bonded SiC bricks cannot be used on a large scale because of their high cost. Therefore, it is essential to devise a new sort of promising candidate erosion resistant material with high performance, low cost, and long service life. ¦Â-sialon is a kind of solid solutions with the formula Si6¨CzAlzOzN8¨Cz ( ) where Si4+ and N3£¿ are partially replaced by Al3+ and O2£¿, respectively. Such replacements without changing the crystal structure only increase the crystal unit sizes [5, 6]. Sialon-based materials are regarded as a promising candidate for erosion resistant materials, because of their excellent
%U http://www.hindawi.com/journals/amse/2014/943542/