Vacuum Resin Infusion Process: A Step-by-Step Guide

Carbon Light Pvt. Ltd.

The Vacuum Resin Infusion Process is a cutting-edge method in composite manufacturing that uses vacuum pressure to draw resin into a dry reinforcement material. It is widely used in industries where high-performance, lightweight, and durable materials are needed, such as aerospace, marine, automotive, and renewable energy.

In this blog, we’ll provide a comprehensive, step-by-step guide to the vacuum resin infusion process, including preparing the mold, applying the infusion mesh, and sealing the vacuum bag.

What is the Vacuum Resin Infusion Process?

The vacuum resin infusion process involves laying dry fibers (like carbon fiber or fiberglass) into a mold and then using vacuum pressure to draw liquid resin into the fibers. This process results in a strong, lightweight composite part with fewer voids and defects than traditional hand lay-up methods.

Beginning the Vacuum Infusion Process

The first step of the vacuum infusion process is preparing the mold and the dry fibers that will form the part’s structure. Here’s how this phase breaks down:

1. Mold Preparation

The mold acts as the shaping tool for the composite part, so it's critical that it is properly prepped before infusion.

• Cleaning the Mold: Remove any debris, dust, or contaminants from the mold surface. This helps ensure a smooth finish on the final part.
• Applying Release Agents: A release agent is applied to the mold to prevent the composite part from sticking to the mold surface after curing. This could be in the form of wax, film, or a specialized chemical agent.

Laying the Dry Reinforcement Fibers

Once the mold is prepared, the dry fiber reinforcement material is laid into the mold. This material could be fiberglass, carbon fiber, or another fiber depending on the strength and weight requirements of the part being produced.

• Cutting and Placing the Fibers: The fibers are cut to the shape of the mold and placed into the mold layer by layer. The fiber lay-up may include layers of woven fiber fabric, mats, or unidirectional fibers, depending on the design.
• Ensuring Fiber Placement: Proper alignment of the fibers is essential to ensure that the final part has the desired strength and stiffness. Wrinkles or misaligned fibers can lead to weak points.

Applying the Infusion Mesh

The infusion mesh plays a critical role in controlling how the resin flows through the fiber layers during the infusion process. It ensures that resin reaches every corner of the mold evenly.

3. Infusion Mesh Application

The infusion mesh is a porous layer placed on top of the dry fibers to aid in the resin’s flow across the entire surface.

• Placing the Mesh: The infusion mesh is cut to match the shape of the fiber lay-up and is placed evenly across the entire surface of the mold. The mesh helps direct the resin flow, ensuring complete saturation of the fibers during the infusion process.
• Smooth Application: Any folds or gaps in the mesh can result in uneven resin flow, leading to voids or weak spots in the final part.

Adding the Vacuum Bag to the Vacuum Infusion Process

The vacuum bag is a crucial component of the vacuum infusion process because it creates the airtight seal necessary for drawing resin into the fiber layers. Without it, the vacuum system would be ineffective.

4. Vacuum Bagging

After the infusion mesh is applied, the next step is to secure a vacuum bag over the mold to create an airtight environment.

• Sealing the Vacuum Bag: A vacuum bag made from plastic film is carefully placed over the entire mold, ensuring it completely covers the dry fibers and mesh. The edges of the bag are sealed tightly against the mold using vacuum sealant tape.
• Connecting the Vacuum Line: A vacuum port is installed in the vacuum bag, allowing a vacuum pump to be connected. The vacuum line will be responsible for drawing air out of the mold.
• Ensuring No Leaks: The vacuum bag must be airtight. Any leaks can prevent the vacuum from pulling the resin through the fibers, resulting in an incomplete infusion.

5. Resin Infusion

Mix the resin and feed it into the mold, allowing the vacuum pressure to pull it evenly through the fibers, ensuring full saturation.

6. Curing

Allow the resin to cure, either at room temperature or with added heat. Keep the vacuum running during curing to maintain pressure.

7. Demolding

Once cured, remove the vacuum bag and demold the part. Trim and finish as needed.

Contact Us

Want to learn more about the vacuum resin infusion process and how it can benefit your projects? Get in touch with our team:

• Website: www.carbon-light.com
• Email: [email protected]
• Follow us on LinkedIn: Carbon Light Pvt. Ltd.

Our team of experts is ready to assist with your composite manufacturing needs!