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Yuhua Fused Cast
The History of Electrofused Bricks
Time：
Sep 19,2026
Electrofused bricks are also known as Fused refractory materials The core manufacturing process involves melting the raw materials at high arc temperatures and then casting them to induce crystallization, which distinguishes this product from conventional sintered refractory bricks. AZS zirconia-alumina fused cast brick It is the most mainstream type of glass used in glass kilns, and its development history is closely intertwined with the evolution and upgrading of the glass industry.
I. Foreign Origins (Early 20th Century to Post–World War II: The Technological Founding Period)
- 1904 Austrian scientists successfully melted high-purity corundum using an electric arc furnace, marking the technological starting point for electrically melted refractories; in its early days, this process was primarily employed in the abrasive materials sector.
- 1926 : Developed by G.S. Fulcher in the United States Electrofused mullite and attempted to incorporate zirconia into mullite, thereby initiating research on zirconia‑containing electrofused materials and laying the groundwork for AZS bricks.
- 1939 T.E. Field found that zirconia‑added fused cast bricks exhibit significantly superior resistance to glass melt erosion compared with electrofused mullite, concluding that they are well suited for glass tank furnaces and thereby establishing the application direction for AZS refractories.
- 1940–1950s : France SEPR Cip , achieved by U.S. company Corhart Industrial mass production of AZS zirconia-alumina bricks , long-term monopoly of the global high-end glass furnace refractory market; concurrently, the Soviet Union initiated fundamental research on the Al₂O₃–ZrO₂–SiO₂ ternary system, thereby refining the theoretical framework of the AZS phase diagram.
- 1960–1980s Europe and the United States have continued to iterate, successively introducing AZS refractories with varying zirconia contents—33#, 36#, and 41#—while also developing electrofused α‑β alumina and high‑zirconia electrofused bricks for use in float glass furnaces. At this time, high‑end electrofused bricks were largely reliant on imports from Europe and the United States.
Core breakthrough at this stage: from pure electrofused corundum/mullite to… AZS zirconia-alumina It has become a key material for glass furnace hearth linings, significantly extending the service life of the furnace.
II. The Development History of China’s Electrofused Bricks
1. The Initial Stage (1950–1970s: Imitation and Pilot-Scale Trials)
Following the founding of the People’s Republic of China, in order to support the flat‑glass industry, domestic research and development of electric‑fused refractories was initiated. Shenyang Refractory Materials Factory It was one of the earliest domestic entities to develop electrofused refractories, primarily replicating Soviet technology. Production was limited in scale and variety, with only small quantities of electrofused corundum and simple electrofused mullite available. AZS zirconia‑alumina refractories are virtually impossible to produce stably on an independent basis, and all large glass furnaces rely entirely on imported Cipre bricks from France. 。
2. The Stage of Breakthroughs in Introduction (1980s: Pushing for Domestic Production)
With the advent of reform and opening-up, the large-scale deployment of float glass production spurred the domestication of electric‑furnace refractory bricks.
- In the 1980s, China introduced foreign technologies for electric‑furnace smelting, casting, and annealing; Liaoning, Henan (Shennai’s Zhengzhou branch, later known as Zhengzhou Zhenzhong), and Shandong established electric‑furnace refractory brick production lines; concurrently, the Sanmenxia Electric‑Furnace Corundum Plant was built to support Baosteel’s projects.
- Successfully achieve Domestication of Ordinary AZS Fused Zirconia–Alumina Bricks , breaking foreign monopolies, yet significant gaps remain in high-end 41# AZS and high-zirconia bricks.
3. Rapid Expansion Phase (1990–2010: Capacity Surge and Domestic Substitution)
Domestic float glass production has expanded rapidly, driving demand for electrofused refractory bricks. Industrial clusters have emerged in Henan and Shandong provinces, with numerous electrofused brick manufacturers coming online; product grades have gradually evolved from 33# AZS. Standard AZS has completely replaced imports and has begun to be exported. 。
Henan has become one of China’s key production hubs for electrofused refractory bricks, with YuHua Electrofused, Zhenzhong, and numerous other electrofused refractory manufacturers emerging during this period.
4. The High-End and Green-Upgrading Phase (2010 to Present)
- Demand for traditional float glass has slowed, while photovoltaic glass, cover glass, and electronic glass are gaining traction, driving… High-zirconia fused cast brick, high-purity α-β alumina fused cast material and the development of high-end products;
- Environmental protection and energy‑consumption controls are tightening, leading to the phase‑out of low‑capacity electric arc furnaces and industry consolidation.
- Leading domestic companies are steadily closing the performance gap with SEPR in high-end AZS and high-zirconia bricks, and the global production hub for fused‑cast refractories is shifting to China, making China… The world’s largest producer and exporter of electrofused bricks ；
- Industry focus: shifting from mere capacity expansion to controlling microstructure, minimizing bubbles, and reducing glass leaching, thereby meeting the stringent requirements of photovoltaic and display glass for resistance to refractory contamination.
III. Brief Historical Summary of the Industry
- 1900s: The birth of electrofused corundum (the origin of abrasives)
- 1926–1950: Mullite → AZS zirconia‑alumina; invention and industrialization, with Europe and the United States holding a monopoly.
- 1950–1980: China was just getting started, producing only small quantities of low-end products, with all high-end goods imported.
- 1980–2000: AZS Achieves Domestic Production Breakthrough
- 2000–2010: Explosive growth in production capacity and widespread adoption of domestic substitution
- 2010 to present: Continuous upgrades of high-end electrofused materials for photovoltaic and electronic glass applications.
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