What are HexMC materials?

When you need components that are both strong and lightweight, traditional materials often force you into frustrating compromises. Steel gives you strength but adds weight that impacts efficiency. Aluminium reduces mass but might not deliver the durability you need.

HexMC materials offer a compelling alternative. These moulded composites combine the best properties of advanced fibres and resins. HexMC represents a significant advancement in composite manufacturing, particularly for industries where weight reduction directly impacts performance and efficiency.

As manufacturers across the automotive, rail and aerospace sectors push for lighter, stronger components, understanding HexMC technology is essential for engineers and procurement specialists. This article explores what makes HexMC materials unique, from the manufacturing process to their impressive performance characteristics. You’ll discover how these materials are made, why they outperform traditional alternatives in specific applications, and where they’re making the most significant impact across different industries.

 

Understanding the basics of HexMC

HexMC, or hexagonal moulded composite, is a type of sheet moulding compound (SMC) that uses precisely cut hexagonal chips rather than the random fibres found in conventional SMC materials. Each chip contains carbon fibres embedded in a thermosetting resin matrix, usually epoxy or vinyl ester. The pieces flow and interlock during the compression moulding process, creating a structure that delivers consistent mechanical properties in all directions.

Where standard SMC uses continuous random fibre strands, HexMC chips create more predictable flow patterns during moulding. It means you can achieve better fibre distribution in complex geometries, reduce resin-rich areas that could become weak points, and maintain more consistent wall thicknesses throughout your component.

The technology emerged from the automotive industry’s need for materials that could match the performance of metal while supporting aggressive lightweighting targets. Major material suppliers developed HexMC systems in the early 2000s, responding to demands for composite solutions that could be processed using existing compression moulding equipment.

 

How HexMC materials are made

Manufacturing HexMC components requires precise control throughout the compression moulding process. But the fundamental steps will be familiar if you’ve worked with conventional composites. The process begins with careful preparation of the HexMC chips, which must be stored at controlled temperatures to maintain their handling characteristics. The moulding team needs to calculate the exact charge weight based on part volume and the required fibre content, typically aiming for 50%-60% fibre volume in the finished component.

The mould loading pattern can significantly impact the quality of the final parts. Unlike SMC, HexMC chips should be distributed more evenly to ensure good coverage while accounting for material flow during compression. The initial charge usually covers 40%-60% of the mould surface area, allowing space for the material to flow and fill any complex features.

Temperature control is critical. The moulds typically operate between 140°C-160°C for epoxy-based resin, with precise heating ensuring it cures properly without degrading.

Compression then transforms the individual chips into a consolidated structure. The hexagonal chips flow and interlock, with the resin carrying the fibres into every detail of the mould cavity. Cycle times generally range from three to ten minutes, depending on part thickness, which is considerably faster than autoclave processing of prepreg carbon fibre.

 

Key benefits of HexMC materials

The weight reduction achieved with HexMC materials can transform your product’s performance. Components typically weigh 30%-50% less than steel equivalents yet maintain comparable strength. This strength-to-weight ratio surpasses aluminium and matches many aerospace-grade materials, yet HexMC processes at lower costs for medium to high production volumes.

HexMC also opens up more design possibilities when compared to traditional metal forming. You can mould complex three-dimensional shapes in a single operation, integrating features like ribs, bosses and mounting points, without secondary assembly. Variable wall thicknesses are achievable within the same component, optimising material use and structural performance. The moulded surface emerges from the tool with excellent quality, often eliminating painting or coating requirements.

HexMC components also offer a high degree of dimensional stability. Low coefficients of thermal expansion mean your parts maintain their shape across temperature ranges, which is crucial for structural applications. The material’s inherent damping properties also reduce noise and vibration, while its resistance to fatigue ensures long service life.

From a sustainability perspective, HexMC materials support a circular economy. The thermosetting matrix can be chemically recycled to recover valuable carbon fibres, and the lightweight properties reduce emissions throughout the product lifecycle. Manufacturing generates minimal waste compared to metal stamping, as off-cuts can usually be reprocessed into lower-grade applications.

 

Applications across industries

The automotive sector drives much of HexMC’s current development. Battery enclosures for electric vehicles benefit from HexMC’s combination of structural strength, electrical insulation and thermal management properties. You’ll also find HexMC in seat structures, where the material’s high strength allows thin sections that maximise passenger space, load floors that support cargo while minimising vehicle weight, and suspension components that can withstand constant loading.

Each application leverages different aspects of HexMC’s capabilities. Sometimes, it’s the weight saving that matters most. Other times, it’s the ability to integrate multiple functions into a single moulded part.

For rail applications, HexMC materials meeting EN 45545 fire standards are replacing metal and traditional composites in interior panels, seat shells and equipment housings. The material’s vibration-damping characteristics reduce noise transmission, improving passenger comfort.

Industrial equipment manufacturers use HexMC for protective covers that resist impact and chemical exposure, structural frames that maintain precision under load, and wear-resistant conveyor components.

And the aerospace sector is increasingly specifying  HexMC for non-critical structures like interior panels and cargo hold linings.

 

How can Talisman Group help?

HexMC materials offer a sophisticated solution to the perpetual engineering challenge of achieving maximum performance with minimum weight. They deliver components that meet the demanding requirements of modern manufacturing.

From EV battery enclosures to rail interiors, HexMC enables designs that wouldn’t be practical with traditional materials. As industries continue pushing for sustainable lightweighting solutions, HexMC technology will likely play an increasingly important role.

At Talisman Group, our compression moulding expertise and technical knowledge mean we’re here to help you explore HexMC’s potential for your applications. Whether you’re looking to convert your existing metal components or develop new lightweight solutions from scratch, our engineering team can guide you through material selection, design and production planning.

Get in touch today to discuss how we can help transform your products’ performance.