Products & Materials


We maintain a rich variety of materials and are armed with state-of-the-art manufacturing and inspection systems – all to produce the best possible products that meet the ever-diverse, sophisticated needs of the customer.

Cast iron materials

“Iron” may sound simple, but it actually comes in a variety of types – each with its own strength and viscosity – according to constituents used and their compositions. At Koyama, we handle over ten different kinds of cast iron materials, out of which we choose the optimal one and choose the manufacturing process best suited to produce exactly the needed product. The same approach applies to product inspection; we employ the inspection method most suitable for the properties of the target iron material.

Light metal (aluminum) alloy materials

Depending on substances added, such as silicon, magnesium and cooper, aluminum alloy cast metal materials vary widely in terms of moldability, corrosion resistance, weldability and so on. So, applicable products and suitable production processes differ according to the types of aluminum alloy materials. Koyama’s long-standing research into materials and rich, on-site manufacturing experience are incorporated in the production of high-performance parts and components based on AC2A, AC4A, AC4B and AC4C alloy materials.