Hua Whakataki: 1, Ko Junda chrome corundum ko te paura alumina hei rauemi mata matua, urutau ki te waikura chromium, te whakarewahia e te oumu arc teitei. 2, he mawhero te tae, he pakeke me te corundum ma he rite, he teitei ake te uaua ki te corundum ma. Ko nga abrasives i hangaia he ahua...
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