The Application Of LFT Thermoplastic Composite Material Molds in Automotive Lightweighting
Apr 20, 2026
With the tightening of global environmental regulations and the increasing demand for the range of new energy vehicles, automotive lightweighting has become a core direction for industrial upgrading. Long fiber reinforced thermoplastic composites (LFT) have become a core material for lightweighting due to their advantages of low density, high specific strength, and recyclability. As a key forming equipment, LFT thermoplastic composite molds directly determine the precision, performance, and cost of components, and are crucial for the implementation of lightweighting. This article, in combination with the characteristics of LFT materials and the demands of automotive production, explores the application points, core scenarios, and development trends of their molds.
I. Compatibility of Core Characteristics of LFT Thermoplastic Composites and Molds
LFT materials are composed of 6-25mm reinforcing fibers (glass fibers, carbon fibers, etc.) and thermoplastic resins (PP, PA, etc.), combining the high strength of fibers with the easy processability of resins. Their density is only 1/4 to 1/3 that of steel, and their specific strength is 30% to 50% higher than that of ordinary short fiber plastic parts. Under equivalent strength, they can reduce weight by 15% to 25%, and they are also impact-resistant and dimensionally stable, meeting the demand of "reducing weight without reducing strength".
LFT molds are mostly made of high-strength steel and are equipped with precise cooling and hot runner systems, which can accurately control molding parameters, preserve the integrity of fibers, and meet the demands of rapid mass production. Compared with traditional metal molds, LFT molds have shorter molding cycles, higher flexibility, lower wear and tear, and can be customized to fit the complex configurations of automotive parts, serving as a core bridge connecting LFT materials with lightweight applications.
II. Core Application Scenarios of LFT Thermoplastic Composite Molds in Automotive Lightweighting
The core application logic of LFT molds is "plastic instead of steel", focusing on body structures, chassis, interiors, and core components of new energy vehicles. Through customized molding, weight reduction and performance improvement can be achieved. The specific scenarios are as follows:
1. Automotive body structural parts
Body structural parts are the core of lightweighting. LFT molds can replace various structural parts by precisely controlling the distribution of fibers. For example, the front longitudinal beam and sill beam, compared with steel parts, can reduce weight by 30% to 40% and increase impact resistance by more than 20%, and can be integrally molded to reduce welding processes. Some body structural parts of BMW i series are formed by LFT molds, ensuring weight reduction and rigidity.
Covering parts such as door inner panels and engine hoods, after being formed by LFT molds, have significantly reduced weight and excellent sound insulation and heat insulation properties, and are suitable for complex curved surface designs. Among them, the door inner panel can reduce weight by more than 28% compared with steel parts, improving the driving and riding experience.
2. Automotive chassis components
Chassis components have extremely high requirements for strength and wear resistance. LFT molds can be used in the production of chassis guards, suspension brackets, battery pack brackets, etc. Chassis guards can reduce weight by 55% compared with steel parts and have better corrosion resistance; the integration of suspension brackets can reduce the number of parts and improve stability.
New energy vehicle battery pack brackets, as core safety components, can achieve a balance between lightweight and high strength through LFT mold forming, reducing weight by more than 30% compared to steel parts, and providing insulation and impact resistance. Some models adopt LFT-D in-line compression molding molds, ensuring the full impregnation of fibers and resins by regulating temperature and pressure to guarantee safety.
3. Automotive interior components
Interior components are numerous and account for a high proportion of the total weight. LFT molds can achieve lightweight production of dashboard frames, seat frames, etc., by optimizing the mold cavity and surface treatment. Dashboard frames can be reduced in weight by 15% to 20% compared to traditional plastic parts, with increased rigidity, and can be integrally formed to reduce assembly; seat frames combine LFT and CFRTP processes to balance weight reduction and support safety.
In addition, LFT mold-formed interior parts are recyclable, and the scraps can be reused, reducing costs and conforming to the green development trend.
4. Special components for new energy vehicles
New energy vehicles have a more urgent need for lightweighting. LFT molds develop customized solutions for battery pack shells, motor shells, etc. Battery pack shells produced by combining microcellular foaming technology with LFT molds can be reduced in weight by 22% and have a 25% increase in impact strength; motor shells can take advantage of the insulation properties of composite materials to simplify insulation structures and reduce complexity.
III. Core advantages of LFT thermoplastic composite material molds in automotive lightweighting applications
1. Facilitating extreme weight reduction while maintaining performance and environmental friendliness
LFT molds can fully leverage the lightweighting advantages of materials, retain fiber integrity, achieve "weight reduction without strength reduction", and the LFT material and mold forming scraps can be recycled, conforming to the green and sustainable development trend of the automotive industry and meeting the requirements of the European ELV legislation.
2. Improving production efficiency and reducing manufacturing costs
LFT molds can be integrally formed to reduce welding and assembly processes, with short molding cycles (LFT-D molds only take 30-60 seconds), suitable for mass production. They have low losses, simple maintenance, and the cost of LFT materials is lower than that of carbon fiber materials, significantly reducing the overall cost of parts.
3. Strong adaptability and meeting customized demands
LFT molds can be custom-designed based on the structure and performance of components, adapting to the needs of different parts such as the body and chassis. They can form complex curved surface coverings and high-strength load-bearing parts, and can be adapted to different types of LFT materials, flexibly adjusting fiber content and resin formulas.
4. Synergistic optimization, promoting the upgrading of lightweighting technology
LFT molds, materials, and forming processes work together, using CAD/CAM and intelligent sensing technologies to improve molding accuracy and consistency; combined with CFRTP materials to form complementary solutions, balancing structural performance and molding efficiency, promoting the upgrading of lightweighting technology.
IV. Problems and solutions in the application of LFT thermoplastic composite material molds in automotive lightweighting
1. Existing main problems
Currently, there are four major bottlenecks in the application of LFT molds: first, insufficient mold precision in China, with uneven temperature and pressure control leading to unstable product performance; second, reliance on imported high-performance mold materials, increasing manufacturing costs; third, difficulty in forming complex-shaped components, prone to defects; fourth, insufficient collaborative optimization of molds and forming processes, affecting lightweighting effects and efficiency.
2. Solution paths
To address the above problems, breakthroughs need to be made in four aspects: first, develop advanced design and manufacturing technologies to optimize mold structure and cooling systems; second, increase research and development of high-performance mold materials to replace imports and reduce costs; third, establish matching models for molds, materials, and processes to improve the quality of complex component forming; fourth, strengthen industry-university-research collaboration to develop customized solutions and accelerate technology implementation.
V. Development trends of LFT thermoplastic composite material molds in automotive lightweighting
In the future, LFT molds will present five major trends:
The first is intelligent upgrading, integrating sensor and control systems to achieve real-time parameter regulation.
Second, modularization and adjustability are emphasized to enhance universality and reduce input costs.
Third, it integrates with new processes such as 3D printing and LFT-D to expand application scenarios.
Fourth, green development, using environmentally friendly materials and processes, and promoting recycling.
The fifth is to accelerate domestic substitution, break foreign monopolies and reduce the cost of lightweighting.
