Low Voltage Electrical Appliances, Various Cores, Shafts, Other Lathe Parts, Cold Forging Parts, Machined Parts.

1.Core functions and application scenarios

The cores, shaft parts, lathe machined parts, cold forgings and machined parts in low-voltage electrical appliances (such as circuit breakers, contactors and relays) jointly constitute the core of the electromagnetic system and the mechanical transmission system. Its functions include:

Electromagnetic conversion: The core (silicon steel sheet/amorphous alloy) guides the efficient transmission of magnetic flux, achieving the conversion of electrical energy to magnetic energy.

Mechanical transmission: Shaft parts (such as rotating shafts and camshafts) bear torque and vibration, ensuring precise and reliable operation.

Structural support: Cold forgings (such as terminals, spring plates) and machined parts (such as bases, covers) provide structural strength and assembly accuracy.

2. Material selection: Precise matching of performance and cost

Core material

Silicon steel sheet: Non-oriented/oriented silicon steel lamination, surface insulating coating (such as alumina) to suppress eddy current loss, suitable for power frequency/medium and high frequency scenarios.

Amorphous alloy: Ultra-low iron loss (70-80% lower than silicon steel), suitable for high-frequency transformers and inductors.

Nanocrystalline materials: high saturation magnetic induction intensity and low coercive force, used in precision relays and sensors.

Shaft material

Carbon steel/alloy steel (such as 45 steel, 40Cr) : High strength and wear resistance, suitable for rotating shafts and camshafts. Heat treatment (quenching + tempering) is required to enhance hardness and toughness.

Stainless steel (such as 304, 316) : Corrosion-resistant and heat-resistant, suitable for humid/corrosive environments.

Aluminum alloy: Lightweight and high thermal conductivity, suitable for scenarios with high heat dissipation requirements (such as relay housings).

Materials for cold forged/machined parts:

Copper alloys (such as brass and bronze) : They have excellent electrical conductivity and are suitable for terminals and contacts.

Engineering plastics (such as PBT, PA66) : Insulating, high-temperature resistant, suitable for bases and covers.

Composite materials (such as glass fiber reinforced plastics) : high strength, low density, suitable for structural components.

3. Processing technology: Precision forming and surface treatment

Core processing

Lamination process: Silicon steel sheets are punched and laser-cut into specific shapes, and then laminated and fixed by welding or riveting to ensure interlayer insulation and magnetic circuit continuity.

Surface treatment: Anodizing, galvanizing, PTFE coating to enhance corrosion resistance; Laser cladding enhances wear resistance.

Shaft processing

Turning/Milling: CNC machine tools achieve high-precision processing of outer circles, inner holes and end faces, with tolerances up to ±0.01mm and surface roughness below Ra0.8μm.

Grinding: Cylindrical grinding and internal hole grinding improve dimensional accuracy and surface quality.

Heat treatment: Quenching + tempering to enhance hardness and toughness, carburizing/nitriding to improve surface wear resistance.

Cold forging processing

Cold heading/hot forging: Cold heading is suitable for mass production of standard parts (such as terminals, spring plates), with high efficiency. Hot forging enhances the density of metals and is suitable for complex-shaped parts.

Surface treatment: Chromium/zinc plating for anti-corrosion, PTFE coating to reduce friction.

Machining of machined parts

CNC machining: Achieving high-precision processing of complex shapes, combined with online inspection to ensure dimensional consistency.

Surface treatment: Sandblasting/polishing improves surface quality, and anodizing enhances the weather resistance of aluminum alloy.

4. Quality Control: Full-process precision and performance verification

Dimensional accuracy: Outer diameter/inner diameter tolerance ±0.01-±0.05mm, length tolerance ±0.1mm, coaxiality/perpendicularity ≤0.02mm.

Surface quality: No cracks, burrs, scratches or other defects, and the uniformity of the anodic oxide film is ≤10%.

Magnetic property tests: core iron loss test (ASTM A343 standard), magnetic flux density (B-H curve).

Mechanical properties: Hardness testing (such as HRC/HV), tensile strength, shear strength, fatigue life testing.

Environmental adaptability: Corrosion resistance is verified through high/low temperature cycling tests and salt spray tests. Vibration testing simulates actual working conditions.

5. Design Optimization: An Innovative Path for Performance Enhancement

Structural optimization

Core: Interlaced laminations reduce magnetic resistance and optimize magnetic circuit paths; Adding heat dissipation fins or thermal conductive coatings can enhance thermal management efficiency.

Shaft parts: Design oil grooves or oil storage holes to improve lubrication; The surface strength is enhanced by rolling threads.

Cold forgings/machined parts: Design bimetallic structures (such as steel back + copper alloy) to balance strength and self-lubricating performance; Add oil holes or oil grooves to optimize the lubrication distribution.

Process optimization

Precision machining: High-precision machining is achieved by using CNC machine tools and grinders. Automated assembly (such as robot press-fitting) enhances efficiency and consistency.

Surface engineering: Advanced surface treatment technologies such as laser cladding and micro-arc oxidation are adopted to enhance wear resistance and corrosion resistance.

Environmental protection and lightweighting: Utilizing recycled materials (such as recycled silicon steel and recycled plastics) to reduce environmental impact; Topological optimization design is adopted to reduce material usage and achieve lightweight.

6. Customized considerations for special scenarios

High-temperature environment: Select heat-resistant alloys (such as Inconel 718) or ceramic coatings, and combine them with high-temperature lubricants (such as graphite-based grease).

Corrosive environment: Stainless steel, titanium alloy or PTFE coating is selected to enhance corrosion resistance. Design a sealed structure to prevent the intrusion of media.

High-precision scenarios: Sub-micron-level precision control is achieved by using optical measurement or laser interferometers. Apply error compensation technology to enhance assembly accuracy.

High-speed/heavy-load scenarios: Optimize material selection and heat treatment processes to enhance wear resistance and fatigue resistance. Design a forced lubrication system (such as oil pumps and oil circuits) to ensure adequate lubrication.