Introduction Manufacturing Process of Motor Iron Core

Have you ever wondered how the heart of an electric motor, the iron core, is made? The manufacturing motor iron core process is crucial for determining the efficiency, performance, and durability of electric motors.

From prototyping to stamping, stacking to winding, and beyond, our advanced manufacturing processes deliver iron cores custom to your precise specifications. In this blog post, we dive deep into the heart of motor iron core technology.

What Is The Electric Motor Core?

Electric motor cores make them vital for the functioning of motors, generators, and transformers. Motor iron cores, comprising stator cores and rotor cores, are essential elements in electrical machines. Motor stator iron cores remain stationary, housing the coil windings, while motor rotor iron cores rotate within the stator. These cores serve as the foundation for creating magnetic fields and facilitating the conversion of electrical energy into mechanical work.

manufacturing motor iron core

Manufacturing Processes for Motor Iron Cores

The core is an important part of the motor, and the manufacturing process of the core has a great influence on the performance of the motor. The core manufacturing process includes design and prototype, stamping and core pressing, stacking assembly and bonding, etc.

Design and Prototyping

Our electric motor lamination stack manufacturing begins with the design and prototyping phase. The engineer’s design depends on the materials used and the engineering technical requirements like the core’s shape, size, and specifications. 

Motor design needs to take into consideration that some space is required for the magnets and that the magnetic field path needs to be optimized. Prototyping allows for testing such as torque curve, rpm per volt, resistance, and impedance before mass production.

Core Stamping and Lamination

Our punching technology of motor iron core uses highly efficiency, highly precise compound die and multi-station progressive die to fabricate.

Our compound die stamping process uses automation feed equipment to deliver the silicon steel sheet to the large press machine, aligning it perfectly with the die. The machine exerts controlled pressure to stamp out each layer of laminations. After the laminate stamping fininshed, our automation machine will laminations the output of the die.

Progressive die stamping uses automatic stamping on high-speed punch. The punching process is that after the lamination steel strip comes out of the coil, it is leveled by the leveling machine. Then automatically fed by the automatic feeding device, and the strip enters the mold.

This process can continuously complete the punching sheet of blanking, forming, finishing, edge cutting, automatic lamination of iron core, blanking with twisted lamination, and blanking with rotary lamination, until the finished products of iron core parts are transported out of the die.

industry electric motor core manufacture capacities

Assembly and Bonding

Our compound stamping laminations need to stack and bond to form the electric motor core. Technicians use rivets, splints, and glue to hold the stacked laminations pieces together. In addition, we use a material with glue for self-bonding.


To prevent short circuits between laminations and windings, we employ injection molding and epoxy powder coating technology for motor lamination stacks insulation.

Quality Control

We have ISO9001:2008 international quality certification. These certifications reflect our strict quality control. Quality control measures include:

Material Inspection

We use silicon steel inspection instruments to inspect the silicon steel sheet used in manufacturing and record the test results.

Motor Manufacturing Process Inspection

Our advanced quality control arsenal includes cutting-edge tools such as Coordinate Measuring Machines (CMM) and Projector Detectors. Ensuring each component within the required dimensions and tolerances to complete.

quality control

Assembly Inspection

Ensures that all components to correctly assembled, and checks for any defects, such as cracks or irregularities in the laminations.

Materials Used in Motor Iron Cores

Motor iron cores use select soft magnetic materials to meet the demands of their applications. We commonly use core materials including electrical steel (silicon steel) with a thickness of 0.1 – 1 mm, 25μm amorphous alloys, nickel alloys, and cobalt alloys. The choice of material impacts the core’s performance, magnetic properties, and efficiency, making it a critical decision in the manufacturing process.

Get High-quality Motor Iron Core From Motorneo

We offer a wide range of motor iron cores, including those for industrial motors, elevator traction motors, servo motors, high vlotage motors, linear motors, switched reluctance motors, and more. Our expertise extends to custom design services, ensuring that you get precisely what your application demands.


As an important part of the motor, the motor core has an extremely important impact on the performance and life of the motor. Appropriate core design and material use can improve the conversion efficiency of electrical energy, improve the stability of the motor, reduce noise generation and magnetic field oscillation of the motor, and achieve more efficient and reliable mechanical energy conversion capabilities.


Why is core lamination important in manufacturing motor iron cores?

The primary purpose of laminating the core involves reducing energy losses within the core, particularly eddy current losses. When the core is constructed of a solid, continuous piece of iron or steel, eddy currents can circulate within it, leading to significant energy dissipation in the form of heat.

By laminating the core into thin, insulated layers, each separated by an insulating material, the circulation of eddy currents is minimized, resulting in significantly lower core losses.

Additionally, core lamination reduces the undesirable humming or noise associated with magnetic flux variation in motors and transformers, making the machinery quieter and more suitable for various applications.

How do materials impact the performance of motor iron cores?

Materials play a pivotal role in determining the performance of motor iron cores in electrical machines. The choice of core material significantly impacts core losses, magnetic properties, and overall efficiency. Common materials used include electrical steel (silicon steel), nickel alloys, and cobalt alloys.

Silicon steel, known for its low core loss characteristics, is favored for applications requiring high efficiency, such as electric motors.

Nickel and cobalt alloys offer improved magnetic properties and higher saturation induction levels, making them suitable for applications where higher magnetic flux densities are required, such as in transformers and high-performance generators.

What is the primary purpose of motor iron cores in electrical machines?

In electric motors, the stator iron core surrounds the rotor and creates a rotating magnetic field when current flows through its windings. This interaction between the stator and rotor forces the rotor to turn, producing mechanical work—powering everything from industrial machinery to household appliances.

In generators and transformers, motor iron cores play a vital role in inducing electrical voltage and regulating voltage levels, ensuring efficient energy transfer and distribution. Essentially, motor iron cores underpin the functionality and efficiency of a wide range of electrical machines.

What are the applications of the motor core?

The motor core is a crucial part of various types of electric motors, and its applications are diverse, as electric motors are used in a wide range of industries and technologies. There are some common applications of motor cores such as industrial motors(conveyor belts, pumps, compressors, fans), electric vehicles (EVs), hybrid vehicles, wind/fire power generators, diesel generators, rail transportation motors, high voltage motors, and elevator traction motors, etc.

Try to contact us for high-quality motor cores in China.