Sourcing Permanent Magnets from China: A Trade-Fair Guide for Engineering and Procurement Teams

2026-10-20

A trade-fair meeting can identify a promising magnet supplier. It cannot establish that the supplier can repeatedly deliver the magnetic, dimensional and assembly performance your product requires. For overseas engineering, sourcing and quality teams, the useful outcome is not a bag of samples: it is a shortlist of suppliers willing to connect a defined requirement to a documented manufacturing route, a repeatable validation method and traceable production records.

This guide focuses on permanent-magnet materials, finished magnets and assemblies. Soft-magnetic cores, inductors and transformers may appear at the same events, but they are not interchangeable sourcing categories. Permanent magnets require resistance to demagnetization; soft-magnetic materials serve different magnetic functions and require different evaluation methods. [1]

Choose the fair around the sourcing question

CWIEME Shanghai — June 23–25, 2027, Shanghai World Expo Exhibition & Convention Center, Shanghai. The organizer lists magnetic materials alongside motor components, manufacturing systems, quality inspection and testing within its coil, motor and transformer manufacturing coverage. It is a relevant setting for comparing how a magnet or magnetic assembly fits into a wider electromechanical production chain. Before arranging meetings, establish whether each exhibitor supplies permanent magnets, soft-magnetic materials, equipment or integration services. The event’s breadth does not mean every exhibitor manufactures magnets. [2]

The 25th Shenzhen small-motor and magnetic-materials exhibition — June 30–July 2, 2027, Shenzhen World Exhibition & Convention Center, Bao’an. The organizer’s Chinese title is “第25届深圳国际小电机及电机工业、磁性材料展览会.” Its published scope expressly includes permanent-magnet materials, soft-magnetic materials, magnetizing equipment, magnetic-material products, and production and inspection equipment. That combination makes it relevant to buyers examining the connection between magnet manufacture, finishing and motor-component integration. A booth offering several material categories still needs to demonstrate the specific route required for your part. [3] [4]

electronica Shanghai — April 14–16, 2027, Shanghai New International Expo Centre, Shanghai. The local organizer uses “electronica Shanghai”; Messe München also lists the event as “electronica China 2027.” Its scope includes sensors, test and measurement, passive components and power supplies. Treat it as an adjacent application and component-sourcing event, not a dedicated permanent-magnet production fair. For a magnetic sensing project, for example, it can help frame discussions about the magnet, sensor and mechanical interface. Check the individual exhibitor’s offering before booking a meeting. [5] [6]

These are organizer-published dates and venues; reconfirm them before committing travel. Shanghai World Expo Exhibition & Convention Center and Shanghai New International Expo Centre are different venues. No statement here implies that Nibboh attends or exhibits at any event.

Bring an application brief, not only a grade name

A magnet grade is one input to a design, not a complete purchasing specification. Material magnetic properties and the behavior of an individual magnet are different: the latter also depends on its geometry and size. Temperature and the magnetic circuit influence the operating point and the risk of irreversible loss. A room-temperature catalogue comparison cannot resolve those questions on its own. [7] [8]

Bring a controlled drawing and a short application brief. Define the magnet’s interfaces, dimensional datums, magnetization direction, polarity convention and required delivered state: magnetized, unmagnetized or assembled. For a multipole component, identify the pole pattern and its angular relationship to a mechanical datum. Include the operating temperature range and relevant process exposure, such as adhesive curing or a downstream heating operation.

Explain the environment and the failure you need to prevent. A sensor magnet may need a specified field component across an air-gap range. A holding assembly may need force at a defined gap and target geometry. A motor component needs an engineering review of its magnetic circuit and demagnetizing conditions. Those are different acceptance problems; asking each supplier simply for its “strongest magnet” obscures them.

Where the design is not frozen, request a manufacturability response that separates proposed changes from confirmed requirements. Do not let a supplier’s preferred stock size, coating or magnetization pattern silently become the approved specification.

Establish who performs each manufacturing step

Ask a prospective supplier to walk through the actual process for the proposed part. Identify the legal entity and production site behind the quotation, then distinguish material production from machining, coating, magnetization, assembly and final inspection. A trading or coordinating business can be useful, but its responsibilities and access to production evidence must be explicit.

For a proposed sintered magnet, ask how the route moves from material preparation and forming through sintering or heat treatment, finishing and inspection, as applicable. For a bonded magnet, ask about the powder and binder system, forming method, tooling and subsequent operations. Sintered and bonded routes are not simply alternative labels for the same component: their processing, achievable geometry and magnetic characteristics differ. Alnico also has established casting and sintering routes. [1] [8]

Request a part-specific process flow identifying in-house and outsourced operations. If coating is subcontracted, for example, ask who approves the processor, who releases the lot and how a failed coating batch is linked back to the magnet lot. If the supplier buys finished blanks, determine which material records it receives and whether those records remain linked after cutting or grinding.

At the fair, a useful follow-up request is one anonymized production example connecting a drawing revision, process flow, batch identity and inspection report. Equipment photographs and a broad product catalogue are not substitutes for that connection.

Validate material, finished magnet and assembly separately

Build the validation plan around three distinct questions: whether the material has the required magnetic properties, whether the finished magnet meets its defined output, and whether the assembly works in the intended application.

Material characterization. IEC 60404-5 describes measurement of permanent-magnet material properties, including magnetic flux density, magnetic polarization, field strength, demagnetization curves and recoil lines. Ask which method is used, which specimen represents the supplied lot, and at what temperature it is measured. Where relevant, review remanence, intrinsic coercivity and the curve shape under the application’s temperature conditions—not only a nominal maximum energy product. The standard’s measurement scope does not by itself establish your product’s acceptance limits. [9]

Finished-magnet verification. Agree the appropriate output measurement and fixture. A Helmholtz-coil measurement can characterize magnetic moment; a Hall probe measures a field component at a location. The latter depends strongly on probe position, distance and orientation. Two suppliers quoting a surface field value without the same setup have not necessarily supplied comparable data. Neither result alone replaces the required material characterization. [7]

For a field measurement, put the reference surfaces, active sensing position, measurement axis and temperature into the test instruction. For magnetic moment, specify the orientation and applicable fixture or coil setup. Correlate the supplier’s and buyer’s methods using identified samples, rather than arguing over readings after the first shipment arrives.

Assembly validation. Test the function after the magnet is combined with the relevant housing, adhesive, target or sensor. Define the actual air gap and interfaces. Where service or assembly exposure could change performance, measure before and after that exposure and specify whether acceptance is evaluated at temperature or after recovery. Magnetic stability and mechanical integrity both matter; a satisfactory material report does not establish adhesive retention or correct pole orientation in an assembly. [8]

If an external laboratory is needed, identify it and confirm the relevant method is within its demonstrated competence and, where required, its accreditation scope. ISO/IEC 17025 concerns testing and calibration laboratory competence; a general certificate should not be read as proof of every proposed magnetic or environmental test. [10]

Specify the coating and its acceptance conditions

For NdFeB, corrosion protection needs to be considered against the operating environment. Surface preparation and control of the coating process matter, not just the coating’s commercial name. [8]

Define the approved coating system, applicable thickness requirements, finished dimensions and relevant adhesion or coverage criteria. Identify the surfaces used for bonding or mechanical contact. Ask how edge damage, chips and coating defects are judged, and how parts are protected during handling. Where adhesive bonding is involved, validate the actual coated surface and preparation process used in production.

Do not turn a salt-spray duration into an assumed service-life warranty. ISO 9227 states that its methods are not intended to predict long-term corrosion resistance or rank different materials against each other. It also leaves product-specific exposure periods and interpretation to the relevant product specifications. Agree the method, applicable edition and amendments, specimen condition, exposure and pass/fail criteria before testing. [11]

Make lot traceability usable after the parts are separated

Ask the supplier to demonstrate a traceability exercise on a real, anonymized lot. Start from a finished-carton label and work back to the production records. Then reverse the exercise: if a material or coating batch is suspect, can the supplier identify every affected shipment?

For your project, agree which links must be retained. Depending on the route, these may include the source material batch, forming or thermal-processing batch, machining lot, coating batch, magnetization operation, inspection results and assembly lot. This is a project requirement to define with the supplier, not an assumption that every supplier already maintains the same records.

Pay attention to split and merged lots, rework and mixed shipments. A certificate that says only “pass” is less useful than a report identifying the part number, drawing revision, lot, test method, results and release decision. Agree how carton and inner-pack labels preserve that relationship when goods are repacked or fed into your production line.

Retain identified samples when they will support later investigation, but do not let a “golden sample” replace controlled specifications. The sample, drawing and measurement procedure must remain consistent.

Approve production conditions, not just attractive samples

Before ordering qualification parts, record whether they will use the intended production site, tooling, material source, subcontractors and process sequence. A sample made by a different route can demonstrate a concept without demonstrating production readiness.

Use the qualification results to decide what evidence is still missing. Dimensional reports, magnetic results and environmental checks should identify the samples tested and their manufacturing history. Request data across relevant production lots and process variation where the risk warrants it. Do not accept a process-capability number without understanding the measurement system, data population and whether the process was stable.

Define the response to a failure before shipment release: containment, investigation, disposition and approval of corrective action. Where a customer requires a formal production-part approval package, agree its content explicitly. An automotive-related exhibition category is not evidence of automotive qualification.

Put changes and supply dependencies into the agreement

Require notification and approval rules for changes that could affect the component. Discuss material source or formulation, forming and thermal processing, production site, coating processor, tooling, magnetization fixture, adhesive, inspection method and packaging. Define which changes require documents, new samples, requalification or written buyer approval. “Equivalent material” should trigger an engineering assessment, not an undocumented substitution.

Separate the quoted production interval from tooling, qualification, externally performed tests and transport. Ask the supplier to identify dependencies rather than compressing them into one optimistic delivery figure. Agree how raw-material price adjustments, tooling ownership, minimum order quantities, order changes and nonconforming goods will be handled for the specific project.

For cross-border supply, assign responsibility for classification, any applicable export or import permissions, transport acceptance and shipment documentation. Verify requirements for the actual product, destination, end use and shipment timing. Do not assume that one magnet material, assembly or prior shipment establishes the treatment of another. Packaging approval should also address chipping, polarity mix-ups, magnetic interaction and preservation of lot identity.

Leave the fair with evidence owners and a release gate

End each serious supplier meeting with a defined next step: who will provide the process flow, who will answer the engineering questions, which samples will be made, and which test method both sides will use. Record unresolved gaps separately from confirmed facts.

A practical release sequence is to confirm the requirement, verify the manufacturing route, qualify representative parts, and approve the production and change-control arrangements before routine supply. Advance a supplier because the evidence closes your project’s risks—not because the booth was impressive or the first sample produced a high gauss reading.

References