1. Detailed explanation of carbon fiber vacuum forming process

Core concept: A composite material forming process that utilizes vacuum negative pressure as the sole or primary pressing force

Seal the carbon fiber reinforced material (dry cloth+resin, or prepreg) stacked on the mold with a vacuum bag

Vacuuming creates an environment below atmospheric pressure (usually ≥ -0.08 MPa), utilizing atmospheric pressure (approximately 0.1 MPa)

Uniformly compact and lay the layer, while combining heating (oven, blanket, or ambient temperature) to make the resin flow, infiltrate the fibers, and cure

2. Characteristics of Vacuum Forming Process

The investment in equipment (vacuum pump, oven) is much lower than that of hot press cans

The cost of molds (often wooden molds, composite molds) is significantly lower than that of high-pressure high-precision metal molds used for hot press cans

Single source of pressure: relying solely on atmospheric pressure (about 0.1 MPa) as compaction pressure, with limited pressure

Relatively uniform pressure: Atmospheric pressure acts on the vacuum bag from all directions, providing better uniform compaction effect (better than contact molding)

Excellent exhaust capability: Continuous vacuum effectively removes air, moisture, and volatile substances, reducing porosity (not as effective as hot press cans)

3. Carbon fiber vacuum forming process

Material Preparation – Lay up – Sealing – Demolding and Post treatment

4. Advantages and disadvantages of carbon fiber vacuum forming process

advantage

Simple equipment and low site requirements: vacuum pumps and ovens (or hot blankets) can meet most of the needs

Excellent adaptability to complex shapes: extremely strong adaptability to curved surfaces, grooves, and large-sized structures

Good surface quality (mold surface): The mold surface can achieve a high degree of smoothness

Effective reduction of porosity: continuous vacuum exhaust, significantly better than open mold contact molding

Relatively easy to operate and learn: the technical threshold is lower than that of the hot press tank

Disadvantages

Mechanical properties are limited: the maximum compaction pressure is only 0.1 MPa, resulting in low fiber volume content (50-55%), high porosity (1-3%+), and significantly lower mechanical properties (especially interlayer strength and compressive strength) compared to hot press products

Resin flow control challenge (wet method): prone to uneven infiltration (poor/rich resin), resin flow, and other issues that affect performance and appearance consistency

Curing temperature and time limitations: limited by oven size, power, or resin system

Reliability of vacuum bag system: There is always a risk of seal failure, which may result in batch scrap

Relatively low production efficiency: layer laying (especially wet methods), packaging time, and curing time may be longer

Double sided quality difference: The vacuum bag surface (non stick surface) is usually rougher and requires additional processing

Volatile matter treatment (wet method): Some resins (such as polyester/vinyl ester) may produce irritating odors or small amounts of VOCs during the curing process

5. Application fields of carbon fiber vacuum forming process; Future Development Trends

Application field

Automobiles: body coverings (hood, spoiler), interior parts, non load bearing structural components, prototype car parts

Ships and oceans: hull, deck components, hatch covers, deflectors, kayaks, paddles

Wind power generation: small and medium-sized wind turbine blades, nacelle covers, fairings

Sports and leisure: bicycle frame (entry-level/mid-range), helmet, surfboard, snowboard, fishing rod, rowing boat (some non main load-bearing components)

Industrial equipment: machine protective covers, panels, brackets, pipelines, tank liners, fixtures and jigs

Architecture and Art: Architectural Decorative Panels, Sculptures, Models, Exhibits

Consumer electronics: drone body (consumer grade), audio enclosure, high-end electronic device enclosure

Aerospace (secondary load-bearing components/interior): fairings, interior panels, ducts, secondary brackets

Future Development Trends

Prepreg optimization: Develop high-performance, low viscosity, and high flowability prepreg (VO Vacuum Only) specifically optimized for vacuum bag processes

Efficiency and Automation

Automated laying application: exploring the application of automatic cutting machines and simple laying equipment in vacuum forming, especially suitable for flat or single curvature components

Rapid curing resin system: Shorten curing cycle and improve production efficiency

Modular/Integrated Equipment: Developing Compact and Easy to Operate Vacuum Heating Integrated Systems

Dry fiber infusion replaces wet method: improves infiltration uniformity and reduces VOCs emissions (although strictly speaking this is a RTM variant, it is often combined with vacuum)

Application expansion: Continuously replacing traditional materials and more expensive processes in the fields of small batch customization and large-scale non main load-bearing structures

Summary

Its core lies in using atmospheric pressure (about 0.1 MPa) to uniformly compact and lay layers through a vacuum negative pressure system, combined with heating (oven/hot blanket/room temperature) to complete resin curing and fiber infiltration