What is Fused Magnesia? A Comprehensive Guide

September 26, 2023

Welcome to our comprehensive guide on fused magnesia! In this article, we will delve into the intricacies of fused magnesia, exploring its properties, applications, and benefits. Whether you're a professional in the industry or simply curious about this fascinating material, we've got you covered. Let's begin!


Understanding Fused Magnesia

Fused magnesia, also known as electrofused magnesia, is a high-purity refractory material with exceptional properties. It is produced by melting natural magnesite in an electric arc furnace, resulting in a dense and highly crystalline structure. The intense heat and controlled conditions of the fusion process ensure the removal of impurities, yielding a product of remarkable purity.

Fused magnesia


Properties and Characteristics

Chemical Composition: Fused magnesia primarily consists of magnesium oxide (MgO) and exhibits a minimum MgO content of 98%. The absence of impurities enhances its performance and makes it ideal for various applications.


Crystalline Structure: The fusion process grants fused magnesia a unique crystal structure, typically cubic or octahedral in shape. This structure contributes to its exceptional strength, thermal stability, and resistance to corrosion.


High Melting Point: Fused magnesia boasts an impressive melting point of approximately 2800°C (5072°F). This high melting point allows it to withstand extreme temperatures, making it suitable for demanding industrial environments.


Density and Hardness: With a density of around 3.5 g/cm³, fused magnesia possesses excellent compactness and durability. Its hardness rating of 8 on the Mohs scale further highlights its resistance to abrasion and wear.


Refractoriness: Fused magnesia exhibits outstanding refractory properties, enabling it to withstand extreme heat and harsh conditions without significant deformation. It retains its shape and integrity even in the presence of molten metals and corrosive materials.


Applications of Fused Magnesia

The exceptional properties of fused magnesia make it indispensable in various industries. Let's explore some of its primary applications:


1. Steel Industry

Fused magnesia plays a crucial role in the steel industry, where it is used for:


Basic Refractory Materials: Fused magnesia forms the foundation of basic refractory materials, which are essential for lining steel furnaces, converters, and ladles. Its high refractoriness, corrosion resistance, and thermal shock resistance make it ideal for such demanding applications.


Slag Conditioner: Fused magnesia acts as a slag conditioner, promoting the removal of impurities and enhancing the quality of steel production.


2. Cement and Construction Industry

In the cement and construction industry, fused magnesia finds applications in:


High-Temperature Insulation: Fused magnesia-based insulation materials are used to line kilns, furnaces, and other high-temperature equipment. Its excellent thermal conductivity and resistance to thermal shock help conserve energy and maintain optimal operating conditions.


Refractory Bricks and Castables: Fused magnesia is a key component in the production of refractory bricks and castables, which are used to construct durable and heat-resistant structures in the construction industry.


3. Other Applications

Apart from the steel, cement, and construction industries, fused magnesia is utilized in various other applications, including:


Foundry Industry: Fused magnesia serves as a refractory material in foundry applications, ensuring the integrity of molds and cores during metal casting.


Glass Production: Fused magnesia's high melting point and resistance to thermal shock make it suitable for glass production, particularly in the manufacture of crucibles, refractory linings, and glass furnace construction.


Ceramics and Porcelain: Fused magnesia is employed in the production of ceramics and porcelain, contributing to their strength, durability, and heat resistance.


Advantages of Fused Magnesia

Exceptional Purity: Fused magnesia's high degree of purity enhances its performance and reliability in various applications.


High Temperature Resistance: Its ability to withstand extreme temperatures without deformation or loss of properties makes it an ideal choice for industries operating in demanding thermal conditions.


Chemical Stability: Fused magnesia exhibits excellent resistance to chemical attack, ensuring longevity and durability in corrosive environments.


Thermal Insulation: The low thermal conductivity of fused magnesia aids in effective insulation, reducing energy consumption and optimizing operational efficiency.


Long Service Life: Fused magnesia's exceptional durability and resistance to wear ensure a prolonged service life, resulting in reduced maintenance and replacement costs.



In conclusion, fused magnesia is a remarkable material with a wide range of applications across diverse industries. Its exceptional properties, including high-temperature resistance, chemical stability, and longevity, make it a preferred choice for critical processes. Whether in the steel industry, construction sector, or other specialized applications, fused magnesia continues to play an integral role in enhancing efficiency and performance. We are a fused magnesia supplier. If you are interested in our products, please contact us now!

Contact Us

+86 189 5430 6666

+86 189 5430 6666

Building B, Kerry Centre Enterprise Square, No.125 Qingnian Street, Shenhe District, Liaoning Province, China.

Copyright © Liaoning Mingshi Refractory Co., Ltd. All Rights Reserved | Sitemap | Technical Support: Reanod