1. Brown corundum abrasive, tumadi esịnede Al2O3, nwere ọkara ike ike, nnukwu siri ike, nkọ ahụ na ọnụ ala dị ala, na kwesịrị ekwesị maka nhazi ọla na elu tensile ike.Ma microcrystalline corundum abrasive na corundum abrasive ojii bụ ihe nrụpụta ya.White corundum White...
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