Nkọwa nkenke:

A na-eji alumina pụrụ iche mee seramiiki seramiiki dị ka ihe bụ isi, agwakọta ya na ọtụtụ obere ụwa gbanwere ihe, ma tinye ya na nnukwu okpomọkụ. Ọ nwere nnukwu ekweghị ekwe na nkọcha onwe ya. Yousheng na-adabere pụrụ iche echiche nke-egweri na-agbakwunye pụrụ iche chemical ka seramiiki abrasive na e ji mara nke oyi ọnwụ. Ihe eji eme seramiiki nwere ike idowe ume na-adịgide adịgide, nke mere na ngwaọrụ abrasive emere nwere ike iru ndụ ogologo ndụ. Abrasive nwere ngwa ngwa sara mbara nke ukwuu, nke enwere ike iji mee ihe maka ịkpụ na ịghacha n'okpuru nrụgide dị elu, na maka ịmịcha ihe dị iche iche dị iche iche, gụnyere gri egweri, ịmị egweri, ịkụcha crankshaft na ndị ọzọ.