Mainrich International

High-Performance Magnets.
Factory Direct.

Zhongshan-based manufacturer. 30+ years. Serving automotive, electronics, and industrial manufacturers worldwide.

Why Mainrich

Quality Guaranteed

  • • IATF 16949 & ISO certified
  • • 100% inspection before shipping
  • • Full traceability on every order
  • • Consistent specs, batch to batch

Factory Direct

  • • Own manufacturing in Zhongshan
  • • No middleman markup
  • • Custom grades and shapes
  • • Prototype to mass production

Reliable Partner

  • • Same-day quote response
  • • Clear, honest communication
  • • On-time delivery track record
  • • Technical support included

What We Supply

Neodymium (NdFeB)

N35 to N55 grades. Sintered and bonded. Custom shapes and coatings.

Samarium Cobalt (SmCo)

High-temp applications. Corrosion resistant. Aerospace and defense grade.

Ferrite

Cost-effective. Isotropic and anisotropic. High volume production.

Magnetic Assemblies

Motor magnets. Sensor assemblies. Custom designs to your spec.

Where We Are

Zhongshan

Headquarters & Manufacturing

London

European Office

Macao

Operations

Zhongshan

NdFeB & Assemblies Factory

Dongguan

Ferrite & Bonded Magnets

Ningbo

SmCo & High-Temp Grades

Our Journey

30+ years of building the supply chain infrastructure that automotive, robotics, and electronics OEMs depend on.

1994

Founded in Hong Kong

Connie Cheang establishes Mainrich International as a trading company, sourcing permanent magnets for electronics manufacturers across Asia.

2001

First Factory Partnership

Enters exclusive partnership with NdFeB sintering facility in Zhongshan, Guangdong. Begins offering custom grades and shapes direct from production.

2005

First Automotive OEM Contract

Wins first direct supply contract with a Japanese automotive Tier-1 for DC motor arc magnets. Annual volume: 500,000 pieces. Triggers investment in 100% inspection capability.

2010

ISO 9001 & Factory Acquisition

Achieves ISO 9001 certification. Acquires controlling stake in Zhongshan factory — transitions from trading model to vertically integrated manufacturer.

2015

IATF 16949 Certification

Passes IATF 16949 automotive quality audit on first attempt. Opens doors to European and American automotive OEMs. Client base grows to 50+ active accounts across 30 countries.

2018

London Office Opens

Establishes European sales office in London to provide local-timezone support for growing UK and EU customer base. Adds Dongguan and Ningbo factory partnerships.

2023

Radial Multipole Launch

Invests in purpose-built radial multipole magnetization equipment. Begins supplying sintered NdFeB radial rings for humanoid robotics and high-speed BLDC motors.

2025

GBD Technology & Export Compliance

Adopts Grain Boundary Diffusion (GBD) technology — reducing heavy rare earth usage by up to 50%. Builds dedicated export compliance team after China's April 2025 rare earth controls take effect. Develops new low-HREE magnet formulations that comply with updated regulations while maintaining performance specs. Runs MOFCOM licensing in parallel with production so shipments never wait.

Inside Our Factories

Four manufacturing facilities across Southern China, each specializing in different magnet technologies and production processes.

Zhongshan NdFeB manufacturing facility

Zhongshan — NdFeB & Assemblies

Our primary facility for sintered neodymium magnets and custom magnetic assemblies. Houses the full production chain from powder processing to finished parts.

Capabilities

  • • Sintering & pressing
  • • CNC grinding (±0.02mm)
  • • Multi-pole magnetization
  • • NiCuNi / Epoxy coating

Equipment

  • • 12 CNC surface grinders
  • • 4 wire-cut EDM machines
  • • Programmable magnetizer
  • • CMM inspection station
Dongguan ferrite and bonded magnet production line

Dongguan — Ferrite & Bonded Magnets

High-volume production of ferrite and bonded NdFeB magnets. Optimized for cost-effective mass production with automated pressing lines.

Capabilities

  • • Wet & dry pressing
  • • Injection molding
  • • Isotropic & anisotropic
  • • Multi-cavity tooling

Capacity

  • • 200 tons/month ferrite
  • • 50 tons/month bonded
  • • 8 pressing lines
  • • 24/7 operation
Ningbo SmCo melting workshop

Ningbo — SmCo & High-Temperature Grades

Specializes in Samarium Cobalt and high-temperature NdFeB grades for aerospace, defense, and energy applications where thermal stability is critical.

Capabilities

  • • SmCo sintering
  • • High-temp NdFeB (200°C+)
  • • Salt spray testing
  • • BH curve measurement

Certifications

  • • ISO 9001:2015
  • • ISO 14001
  • • IEC 60068 testing
  • • Full lot traceability
Quality control and shipping operations

Quality Control & Logistics

Centralized QC across all facilities with standardized inspection protocols. Every batch is tested before shipping — dimensional, magnetic, coating adhesion, and visual.

QC Equipment

  • • Helmholtz coil systems
  • • Gaussmeters (DC & AC)
  • • Coordinate Measuring Machine
  • • X-ray fluorescence analyzer

Standards

  • • IATF 16949 automotive
  • • PPAP documentation
  • • 100% incoming inspection
  • • CPK tracking per lot

4

Manufacturing Sites

35+

CNC Machines

300+

Production Staff

500t

Annual Capacity

Let's Talk

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