Expanded-glass spheres are also known as glass microspheres and glass bubbles. They are used for lightweight fillers in various industries, such as automotive, construction, and aerospace. These spheres consist of glass heated and expanded in a fire, creating a lightweight, low-density product.

This article explores the advantages and characteristics of expanded glass globes. It also discusses the various types of spheres and their application.

Expanded Glass Spheres

Expanded glass is made by heating glass and expanding it in a kiln. This produces a low-density, lightweight product with many unique characteristics. Some of the most important properties of expanded spheres include

  • They Are Lightweight: Because they have a lower density than traditional fillers like sand or Clay, expanded glass spheres weigh less.

  • High Weight-to-Strength Ratio: Despite their low weight, expanded glass balls are very strong.

  • High Thermal Conductivity: Expanded glass balls have a very low thermal resistance, which makes them excellent insulators.

  • Resistant to Acids and Alkalis: Expanded glasses spheres have chemical resistance to many acids and most alkalis.

  • No Toxic: Expanded glass spheres are not toxic and do not pose any health risks.

Expanded Glass Spheres

There are many types of expanded spheres, each having its own advantages and specific properties. Some of the most common types are:

  • Solid Spherical: The solid expanded sphere is the most common type of glass sphere. It can be used in many applications, such as fillers or coatings.

  • Spheres Hollow: Expanded glass hollow spheres provide greater insulation and lower density than solid expanded spheres.

  • Coated Spheres: The expanded glass spheres that are coated have a thin layer of resin. This provides an additional barrier against moisture as well as improved adhesion.

  • Conductive Balls: Conductive expanded-glass spheres come with a thin film of conductive materials, making them perfect for electronic use.

Expanded Glass Spheres – Advantages

Expanded glass balls have unique properties that make them superior to other filler materials. Among the many advantages are:

  • Lightweight: Because of their low density, expanded glass spheres are much lighter than filler materials with a higher density. This reduces the weight of final products, which has a major impact on the aerospace and auto industries.

  • High Strength-to-Weight Ratio: Despite the low density of expanded glass, they offer a very high strength-to-weight ratio. They are, therefore, a better alternative than traditional fillers like Clay or sand.

  • Insulation: Expanded glass spheres have a very low thermal resistance, making them effective insulators. This property makes the spheres useful in insulation applications, such as building materials or automobile parts.

  • Chemical Inertness: Expanded glass spheres are chemically non-reactive and resistant to most acids and alkalis. This makes them suitable for harsh environments.

  • Safe Alternative: Expanded glasses spheres do not pose health risks and are a non-toxic alternative.

Expanded Glass Spheres

Expanded-glass spheres have a wide variety of uses and applications.

Construction: Expanded glass spheres can be used as lightweight fillers in various construction materials, such as concrete and mortar.

Automotive: Expanded glasses spheres can be used as a filler in automotive components such as dashboards.

Coatings: Expanded Glass Spheres reduce the weight of coatings like paints and stains and improve their properties.

Composites: Expanded glasses spheres can be used in composites such as fiberglass to improve strength and reduce weight.


Expanded glass balls offer many advantages over conventional fillers, including low density, high weight-to-strength ratio, insulation properties, and chemical resistance. This unique combination of properties makes them ideal for various industries and applications.