Sourcing Silicon Nitride Powder from China

Silicon nitride powder pays 4%

Read from the UK Trade Tariff on 6 November 2026, heading 2850 covers hydrides, nitrides, azides, silicides and borides, excluding compounds which are also carbides. Silicon nitride powder falls within the other hydrides and nitrides line, 2850 00 20 90. The table shows specification variants sharing this commodity code.

Goods from China carry 4% duty, with no anti-dumping or countervailing duty recorded. The suspension on this line names other substances and does not cover silicon nitride. The tariff attaches import and export waste controls. Waste shipment controls apply only when the material is waste; for waste powder from China, confirm the applicable requirement with your customs broker before shipment.

Confirm the composition and powder form through finding your commodity code. Finished ceramic parts need classification by their form. For related products within the wider heading, see boron nitride powder.

Specify crystal phase, oxygen and particle size

State the required alpha and beta phase composition, purity, oxygen, carbon, free silicon and metal impurity limits. Agree particle size distribution, specific surface area and the test methods. Ask the supplier to distinguish untreated powder from material containing sintering additives or binders.

Approve a sample in your own ceramic process before accepting production stock. Specify sealed packing, batch identification and a certificate of analysis for each lot. Compare the supplied powder with the approved sample using the same preparation and measurement methods.

For Great Britain, confirm applicable UK REACH registration responsibilities, any proposed only-representative coverage, safety data sheet obligations and classification and labelling requirements with HSE before supply. Confirm the route for the actual powder formulation.

Worked duty example

Illustrative example, not a quote: Illustrative order: 2 tonnes of silicon nitride powder under 2850 00 20 90, invoiced at £50,000 free on board, with £2,000 of freight and insurance to the UK. The customs value is £52,000. Duty at 4% is £2,080. Import VAT at 20% is charged on the customs value plus duty, £54,080, so it is £10,816. Import taxes total £12,896; a VAT-registered importer can usually reclaim the VAT, so the lasting cost is the £2,080 of duty. The import duty and VAT guide explains each step.

Inspection checklist

Identity: match the order, container labels and batch certificate; check whether additives or binders have been included.

Composition: independently sample the lot and compare crystal phase, oxygen, free silicon and agreed impurities with the specification.

Particle behaviour: check particle size distribution and agglomeration against the approved sample; record the preparation method.

Packing and documents: inspect seals, moisture damage and batch traceability; check the English safety data sheet where required and the UK REACH arrangement.

What goes wrong

A powder can match the headline purity yet fail your process because its phase composition, oxygen content or particle distribution differs from the sample. Agglomerates and inconsistent sample preparation can also produce misleading particle size comparisons.

Damaged seals, mixed batches and undocumented additives make incoming checks harder. Keep suspect lots separate until testing resolves the discrepancy. Agree sampling and acceptance methods before dispatch using the quality inspection guide.

Cambridge China Bridge sources these products for UK businesses, checking the factory and the documents before shipment. See factory verification. For repeat volumes, see container programmes.