China
Africa
Explore chapters and articles related to this topic
Crucible Materials
Published in Nagaiyar Krishnamurthy, Metal–Crucible Interactions, 2023
Refractory materials may be broadly grouped into siliceous, aluminous, aluminosilicates, magnesite, dolomite or chrome ore and inevitably, the miscellaneous category of special refractories. Refractories are used in two basic forms: (i) pre-shaped objects (bricks and shapes) and (ii) unformed compositions or monolithics.
Heat Transfer Applications
Published in Theodore Louis, Behan Kelly, Introduction to Optimization for Environmental and Chemical Engineers, 2018
Industrial thermal insulation usually consists of materials of low thermal conductivity combined in a way to achieve a higher overall resistance to heat flow. Webster4 defines insulation as, “to separate or cover with a non-conducting material in order to prevent the passage or leakage of…heat…etc.” Insulation is defined in Perry’s1 in the following manner: “Materials or combinations of materials which have air or gas-filled pockets or void spaces that retard the transfer of heat with reasonable effectiveness are thermal insulators. Such materials may be particulate and/or fibrous, with or without binders, or may be assembled, such as multiple heat-reflecting surfaces that incorporate air or gas-filled void spaces.” Refractory materials also serve the chemical process industries. In addition to withstanding heat, refractory also provides resistance to corrosion, erosion, abrasion, and/or deformation.
Introduction and General Overview
Published in A. Schacht Charles, Refractory Linings, 2017
Refractory structures exhibit similar structural behavior as the block type or stone structures. However, refractory structures are exposed to a more complicated load environment: thermal expansion loading. The refractory lining is typically exposed to high temperatures resulting in complicated stress/strain environments within the lining structure, and the refractory material properties tend to vary as a function of temperatures. High temperatures have a profound influence on the refractory material properties. At high temperatures, refractory materials no longer remain totally elastic. Instantaneous plastic and time-dependent creep straining takes place. As a result, the structural investigation often requires the use of computerized structural analysis methods that can deal simultaneously with these complex material and structural behaviors.
A novel dense Al2O3-Ti2O3 slag synthesized while ferro-titanium alloy making
Published in Journal of Asian Ceramic Societies, 2022
Qingyao Zheng, Yong Li, Chenhong Ma, Xiaofang Wu, Hezhen Li, Jialin Sun
The paper proposes a new process to produce ferro-titanium alloy, which can produce ferro-titanium alloy and at the same time obtain a slag material with high added value. The material has broad application prospects for the following reasons. (1) It exhibits the corundum-like high-temperature properties and, therefore, can be used as a refractory material. (2) Dispersing Ti2O3 among corundum grains can increase their toughness to produce an ideal abrasive material [13]. (3) The presence of titanium compounds can be controlled through process optimization. While the reaction Ti2O3 + O2 + Al2O3 → Al2O3 + Al2TiO5 occurs in an oxidizing atmosphere, the TiC/TiN/TiCN corundum-based composite material is formed in a reducing atmosphere [14]. (4) The Al2O3–Ti2O3 composite is easy to obtain and environmentally friendly; furthermore, it increases the utilization rate of natural resources.
Property analysis of thermal insulating materials made from Ghanaian anthill clay deposits
Published in Cogent Engineering, 2020
Industrial furnaces have been the backbone of metallurgical companies for ages. Metallurgical industries use these furnaces in their day-to-day processing of various metals. The furnaces use supplied heat energy from external sources to transform metallic ores into various useful products at elevated temperatures. However, efficiencies of these furnaces are not at their maximum. This deficiency is mostly attributed to energy leakages from the furnaces. Several researchers are looking at ways of improving the efficiencies of the various parts that make up these furnaces (Bonilla-Campos et al., 2019; Royo et al., 2018; Sadik et al., 2014; Wang et al., 2019). One of such parts is the refractory. A refractory must be able to withstand sudden changes in temperatures, conserve heat and must have low coefficient of thermal expansion. It should also be able to withstand the action of abrasive or corrosive solids, liquids or gases at high temperatures (Akinwekomi et al., 2012). Refractories are therefore used to provide linings for high-temperature furnaces, ovens, reactors and ladles to prevent escape of heat to the surrounding environment (Ajala & Badarulzaman, 2016; Gupta, 2016). Numerous materials have been used in the fabrication of the refractory materials (Sadik et al., 2014). However, all of these materials are still not able to completely trap the supplied heat within the furnace system (Ajala & Badarulzaman, 2016; Hadała et al., 2017; Sardeshpande et al., 2010).