Types of Alumina Explained: 7 Major Grades, Properties & Industrial Uses (2025 Guide)

Date: November-20-2025 Categories: News、Alumina Views: 34

Types of alumina overview showing main alumina grades and applications

If you work with ceramics, refractories, polishing or flame-retardant compounds, you already know that not all alumina is the same. There are many types of alumina. Each type has its own crystal phase, surface area, particle size and purity. Each type fits a different industry need.

This guide explains the most common types of alumina used in modern industry. It is written for engineers, buyers, and sourcing teams. It is also helpful for distributors who buy from a Manufacturer, Supplier or Factory in China and sell alumina in Wholesale packages to global customers.

Table of Contents

1. What Are the Main Types of Alumina?

Alumina is the oxide of aluminum, with the formula Al2O3. It can exist in different crystal phases and different structures. This is why there are many types of alumina. Each type shows different hardness, porosity, surface area and reactivity.

In industry, the most widely used types of alumina include:

  • Alpha alumina (α-Al2O3)
  • Calcined alumina
  • Tabular alumina
  • Activated alumina (γ-Al2O3)
  • Fused alumina (white fused and brown fused)
  • Alumina trihydrate (ATH)
  • High purity alumina (HPA)

When we talk about types of alumina, we usually refer to these seven key groups. The sections below explain each type, its main properties and typical uses.

Quick Facts About Alumina Types

  • Different crystal phases mean different performance.
  • Firing temperature changes the final alumina structure.
  • Porous alumina is good for catalysts and drying.
  • Dense alumina is ideal for refractories and wear parts.
  • Fine particles are used in polishing and precision ceramics.

2. Alpha Alumina (α-Al2O3)

Alpha alumina is the most stable crystal phase of alumina. It is very hard, dense and chemically inert. Many types of alumina are actually alpha alumina in different particle forms.

Key Properties of Alpha Alumina

  • Very high hardness and wear resistance
  • High melting point and good thermal stability
  • Low porosity in dense sintered form
  • Good electrical insulation

Common Applications

  • Technical ceramics and structural parts
  • Ball and lining media for mills
  • Abrasion resistant tiles and pipes
  • Electrical insulators and spark plug parts

When a Manufacturer, Supplier or Factory talks about alumina ceramics, they usually mean ceramics made mainly from alpha alumina powder. Buyers who compare different types of alumina for advanced ceramics often choose alpha alumina for its stability and durability.

3. Calcined Alumina

Calcined alumina is produced by firing aluminum hydroxide at high temperature. The firing process removes bound water and converts the material into stable alumina. It is one of the most important types of alumina in industry.

Calcined alumina powder – common type of alumina for ceramics and polishing

Key Properties of Calcined Alumina

  • Controlled particle size, often sub-micron to several microns
  • High whiteness and chemical purity
  • Good flow and packing behavior
  • Suitable for sintering and reaction with other oxides

Common Applications

  • Fine ceramics and spark plug bodies
  • Polishing powder and lapping compounds
  • Glazes and advanced refractories
  • Filler in special plastics and rubber

For more details, you can see the dedicated page on calcined alumina Manufacturer & Supplier – BanlanChem. That page goes deeper into calcination conditions, grades and polishing uses.

Many buyers who search for types of alumina end up choosing calcined alumina for polishing or high density ceramics. It is easy to source in Wholesale quantities from a reliable Factory.

4. Tabular Alumina

Tabular alumina is a special type of alpha alumina. It is made by sintering high purity alumina at very high temperature, close to the melting point of alumina. The result is large, well-developed “tabular” or plate-like crystals.

Tabular alumina crystals showing dense alumina type for refractories

Key Properties of Tabular Alumina

  • Very low porosity and very high density
  • High thermal shock resistance
  • Excellent corrosion and abrasion resistance
  • Stable at very high service temperatures

Common Applications

  • Refractory castables and bricks for steel and cement
  • Slag resistant linings and burner blocks
  • Refractory precast shapes

You can check BanlanChem’s tabular alumina product page for typical sizes and chemical analysis. For more background on uses and performance, you may also read the article tabular alumina supplier – applications and properties.

Among all types of alumina, tabular alumina is one of the best choices for high-performance refractories. Refractory producers prefer stable supply from a professional Manufacturer and Supplier to keep quality consistent.

5. Activated Alumina (γ-Al2O3)

Activated alumina has a very high surface area and a porous structure. It is usually based on gamma phase alumina. It is different from dense alpha alumina and from tabular alumina. This type is used more for surface reactions, adsorption and drying.

Activated alumina beads – high surface area alumina type for adsorption

Key Properties of Activated Alumina

  • High specific surface area
  • Porous structure with many active sites
  • Good crush strength in formed beads
  • High water adsorption capacity

Common Applications

  • Desiccant for air and gas drying
  • Catalyst and catalyst carrier in petrochemicals
  • Fluoride removal from water
  • Refining and adsorption processes

When selecting among types of alumina for catalyst or adsorbent use, activated alumina is often the first choice. Many plants buy it in Wholesale quantities as beads or shaped bodies from a specialized Factory and Supplier.

6. Fused Alumina (White and Brown)

Fused alumina is made in an electric arc furnace. Alumina or bauxite is melted, then cooled and crushed. Two major types of alumina fall in this group: white fused alumina and brown fused alumina.

White fused alumina grit – high purity alumina type for abrasives and refractories

White Fused Alumina

  • High purity, usually from calcined alumina
  • Very hard and sharp
  • High whiteness, low impurities

Typical uses:

  • Bonded and coated abrasives
  • Blasting media for stainless steel and glass
  • Refractory castables and bricks

You can see more details on BanlanChem’s white fused alumina product page. It is designed for both abrasive and refractory customers who need stable quality from a reliable Manufacturer and Wholesale Supplier.

Brown Fused Alumina

  • Made from bauxite, contains some TiO2 and other oxides
  • Very tough and strong
  • Deep brown color

Typical uses:

  • Heavy-duty grinding wheels
  • Anti-skid surfaces
  • High wear resistant linings

For abrasive users, these types of alumina are often the most cost-effective choice. Many plants work directly with a Factory in China for stable Wholesale supply.

7. Alumina Trihydrate (ATH)

Alumina trihydrate (ATH) is aluminum hydroxide, often written as Al(OH)3. Strictly speaking, it is not the same as calcined alumina. But in real business, many buyers see ATH as one of the practical types of alumina because it is made from the same bauxite chain and used in similar industries.

Key Properties of ATH

  • Decomposes and releases water at high temperature
  • Acts as a flame retardant and smoke suppressor
  • High whiteness and low oil absorption in special grades
  • Non-toxic, halogen-free additive

Common Applications

  • Flame retardant filler in cables and wires
  • Filler in plastics, rubber and thermoset resins
  • Solid surface materials and artificial marble
  • Paper and coating industries

For filler uses, BanlanChem offers high whiteness aluminum hydroxide for filler. It is a good option for customers who need a consistent Manufacturer and Supplier for ATH-type products.

8. High Purity Alumina (HPA)

High purity alumina (HPA) is usually 99.9% Al2O3 or higher. Many types of alumina described above have high purity. But HPA is a special category used in advanced technologies.

Key Properties of HPA

  • Very low Na2O and other impurities
  • Excellent insulation and dielectric strength
  • Control over particle size, from nano to micron
  • High optical and surface quality in some grades

Common Applications

  • Sapphire substrates and LED components
  • Battery separators and ceramic fillers
  • Advanced electronic ceramics
  • Special polishing and CMP slurries

When buyers compare types of alumina for high-tech use, they look not only at phase but also at ultra-low impurities. In this segment, working with a trusted Manufacturer and Factory is critical for stable performance.

9. How to Choose the Right Type of Alumina

Choosing between different types of alumina can be confusing. A simple way is to start from your end use and work backward.

Step-By-Step Selection Tips

  • Define your application – refractory, ceramic, filler, polishing, adsorbent, etc.
  • Set key properties – hardness, density, porosity, surface area, purity.
  • Check operating temperature – room temperature, 200°C, 1,000°C or higher.
  • Consider process – pressing, casting, extrusion, molding, coating.
  • Compare cost vs. performance – some alumina types are premium grades.
  • Talk to the Manufacturer or Supplier – ask for data sheets and samples.

For example, if you need a dense refractory, tabular alumina is usually better than activated alumina. If you need a desiccant, activated alumina is better than dense alpha alumina. This is why understanding the main types of alumina can save you both time and cost.

10. Grades, Particle Size and Purity Levels

Even within the same type, there are many alumina grades. A good Manufacturer, Supplier or Factory will offer a clear grade list with typical data.

What Usually Changes Between Grades?

  • Particle size (D50) – from very fine to coarse
  • Surface area – especially for activated alumina
  • Na2O and other impurities
  • Loss on ignition (LOI)
  • Bulk density and tap density

When you compare types of alumina and their grades, ask your Supplier for a technical data sheet. Then match the numbers with your own formula targets.

11. Why Work with a Professional Alumina Manufacturer & Supplier

BanlanChem alumina manufacturer and supplier factory in China – wholesale alumina products

For many users, alumina is a core raw material. Stable supply and quality are more important than a small price change. This is why it is wise to work with a professional alumina Manufacturer, Supplier and Factory.

What a Good Alumina Supplier Should Offer

  • Clear product lines for different types of alumina
  • Stable quality and repeatable batches
  • Technical support for grade selection
  • Flexible packaging and Wholesale options
  • Fast response on documents, COA and MSDS

BanlanChem focuses on aluminum hydroxide and alumina series products. The company works as a dedicated Manufacturer, Supplier and Wholesale Factory in China. Many customers source different types of alumina from one partner to simplify their supply chain.

12. FAQ About Types of Alumina

Q1. How many main types of alumina are used in industry?

In practice, most plants work with seven key types of alumina: alpha alumina, calcined alumina, tabular alumina, activated alumina, fused alumina (white and brown), alumina trihydrate (ATH), and high purity alumina (HPA). Other special forms are usually sub-types inside these groups.

Q2. Which type of alumina is best for refractories?

For high-grade refractories, tabular alumina and white fused alumina are very common. They offer high density, low porosity and good thermal shock resistance. Some formulations also include calcined alumina as a fine matrix.

Q3. Which type of alumina should I choose for flame retardant filler?

For flame retardant and smoke suppression, alumina trihydrate (ATH) is the standard choice. It releases water when heated and helps to slow down fire. BanlanChem’s high whiteness aluminum hydroxide filler is designed for this kind of application.

Q4. Which type of alumina is used as a desiccant and catalyst support?

Activated alumina is used for both gas drying and as a catalyst carrier. Its porous structure and high surface area make it very effective. Among all types of alumina, it has one of the highest surface areas.

Q5. Can one plant use more than one type of alumina?

Yes. Many factories use several types of alumina at the same time. For example, a refractory plant may use tabular alumina for coarse fractions, calcined alumina for the fine fraction, and white fused alumina for special high wear parts. A cable compound plant may use ATH as filler and alpha alumina in some special masterbatches.

Q6. How can I start working with BanlanChem for alumina supply?

You can visit https://banlanchem.com and send your inquiry with target application, annual volume and required types of alumina. The team can suggest suitable grades, supply samples, and quote Wholesale prices from the Factory.

By building a clear content structure around the main types of alumina, and linking to detailed product pages and articles, your website can give real value to users and help Google better understand your expertise as a professional alumina Manufacturer, Supplier, Factory and Wholesale partner.

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