Silicon and tungsten carbide from China
Carbides from China, including black and green silicon carbide grain and powder, tungsten carbide powder, boron carbide and calcium carbide, pay 4% UK duty on all seven lines, with no anti-dumping duty. Abrasive grain is bought on grit size, tungsten carbide on carbon and particle size, and calcium carbide is dangerous when wet. Cambridge China Bridge sources carbides.
Silicon carbide grain, tungsten carbide powder, boron and calcium carbide from China pay 4% UK duty. Grit sizing, carbon checks, UN 1402 and an example.
4% duty
Read from the UK Trade Tariff on 26 September 2026, carbides whether or not chemically defined, heading 2849, carried 4% on goods from China on all seven lines: calcium carbide (2849 10 00 00), silicon carbide (2849 20 00 00), boron carbide (2849 90 10 00), tungsten carbide (2849 90 30 00), tantalum and other carbides. No line had an anti-dumping measure or a suspension.
Cemented carbide inserts, tips and rods sintered with a binder are tool parts of heading 8209, abrasive grain bonded into wheels is in our grinding and cutting wheels guide, and coated abrasives are in the sandpaper guide. Tungsten metal powder is in our tungsten products guide.
| Goods | Commodity code | Duty | Anti-dumping duty on China |
|---|---|---|---|
| Calcium carbide | 2849 10 00 00 | 4% | None |
| Silicon carbide | 2849 20 00 00 | 4% | None |
| Boron carbide | 2849 90 10 00 | 4% | None |
| Tungsten carbide | 2849 90 30 00 | 4% | None |
| Other carbides | 2849 90 90 00 | 4% | None |
Safety and REACH
Calcium carbide releases flammable acetylene with water and ships as UN 1402, a class 4.3 dangerous-when-wet substance, in sealed steel drums. Fine silicon carbide and tungsten carbide powders need dust controls, and the safety data sheet must be in English.
Importing one tonne or more a year of a substance needs a UK REACH registration or an only representative, so check the position for each carbide before the first order.
Specifying carbides
Silicon carbide is sold as black grade for grinding and refractories, green grade for harder, purer uses, and metallurgical grade for steelmaking; specify silicon carbide content, free carbon, free silicon, iron and the grit or particle size. Tungsten carbide powder is specified by total and free carbon, oxygen, particle size and impurities, because those set the properties of the cemented carbide made from it.
Worked duty example
Take a hypothetical order of 25 tonnes of black silicon carbide abrasive grain, entered under 2849 20 00 00: £30,000 free on board plus £2,500 of freight and insurance gives a customs value of £32,500. The 4% duty on silicon carbide comes to £1,300, and import VAT is 20% of £33,800, which is £6,760. If you are VAT-registered you normally reclaim the £6,760, leaving £1,300 as the real cost at the border. Step by step: UK import duty and VAT.
Inspection checklist
Grit size: check abrasive grain size distribution by sieving against the F grit designation of ISO 8486-1 on samples from several bags, since oversize grains scratch and undersize grains cut slowly.
Chemistry: test silicon carbide content, free carbon and free silicon by chemical analysis, and for tungsten carbide total and free carbon and oxygen against the certificate.
Particle size and packing: measure tungsten carbide powder particle size by the Fisher sub-sieve method of ASTM B330 or laser diffraction as agreed, check bags or drums are sealed and dry, and check calcium carbide drums for UN 1402 marking and dents.
What goes wrong
Carbides fail on purity and sizing. Silicon carbide comes in with more free carbon or iron than stated, grit bags contain oversize grains that scratch the work, green grade is swapped for black, tungsten carbide powder varies in carbon so the sintered parts are brittle or porous, and calcium carbide drums leak and let in moisture.
Test the first lot in a UK laboratory, sieve-test grain from several bags, and agree packing and dangerous goods handling in the contract. See our quality inspection guide.
Cambridge China Bridge sources silicon carbide, tungsten carbide and other carbides for abrasive, refractory and hard-metal producers, usually by the full container. See container programmes.
Frequently asked questions
What is the UK import duty on silicon carbide from China?
Read from the UK Trade Tariff on 26 September 2026, silicon carbide (2849 20 00 00) carried 4% from China, with no anti-dumping duty.
Are carbide inserts the same code?
No. Sintered cemented carbide inserts and tips are tool parts of heading 8209.
Is calcium carbide dangerous goods?
Yes. It ships as UN 1402, class 4.3, because it releases acetylene with water.
How do I check abrasive grit size?
Sieve samples against the F grit designation in ISO 8486-1.