Aluminum matrix composites increase the power density of the motor
Aluminum-based composites also reduce mass and inertia and improve the energy efficiency and responsiveness of motors in electric vehicles
According to Innovate UK’s “Make it Lighter with Less” research and development competition, engineers seeking to significantly improve motor efficiency and performance can benefit from the use of aluminum matrix composites (AMCs). The project was developed by AMC expert Alvant in cooperation with GE Aviation Group, YASA Automotive and the National Composites Center to achieve 40% rotor weight reduction on axial flux motors while increasing the rotor’s power to inertia ratio. In addition, the number of assembly line components is reduced, which can be repeated in a shorter assembly time.
As electrification increases, vehicle manufacturers are seeking to optimize motor efficiency maps, such as by increasing efficiency as a function of torque and speed, ultimately determining vehicle energy consumption. The industry faces the challenge of identifying ways to improve efficiency and performance while simplifying manufacturing and overall costs.
Alvant’s proprietary AMC accurately optimizes component strength – weight and stiffness – weight ratio where needed, even in a single continuous product. Alvant’s unique proprietary Advanced Hydroforming (ALPF) method can use one of the performance materials to selectively enhance the part area in a near net shape manufacturing process, or Alvant’s material can be applied as a discrete insert to the assembly, thus achieving cost effectiveness. A similar set of insertions is the solution.
By using AMC in the rotor design, Alvant can achieve further benefits. In axial flux motor applications for passenger cars, Alvant’s technology not only reduces weight; the lower quality and reduced strength of the assembly means engineers can eliminate the number of fixing bolts required, thus reducing bill of materials and Assembly time.
Alvant Commercial Director Richard Thompson said:
“With AMC, we are able to attack weight while maintaining the stiffness of the electric rotor, minimizing parasitic mass and increasing the power inertia ratio for improved efficiency and responsiveness. In addition, we can provide better resistance up to 300 °C. Thermal properties make AMC a more suitable material than polymer composites for applications such as motors, batteries, energy recovery systems, fans and flywheels.
In addition to manufacturing and in-service benefits, Alvant’s AMC is more sustainable thanks to the ability to separate fibers from aluminum during the end of life.
Richard Thompson added:
“Designers must increasingly incorporate lifetime costs into their design, which is a good area for AMC scores.”
While the Innovate UK / YASA program focuses on passenger car rotors, Alvant’s own research projects demonstrate the benefits of AMC in a variety of high-stress or high-temperature applications such as aerospace, automotive, defense, consumer goods and sports equipment.