| 摘要 |
<p>The invention concerns melted alumina-zirconia grains corresponding to the following chemical composition, expressed in mass %: ZiO2 + HfO2 10.60 %; Al2O3 38 to 90 %; SiO2 < 0.8 %; impurities < 1.2 %, characterised in that they have a slightly reduced state such that the grains contain less than 100 ppm of carbon and have: a) a porosity, defined by the number of pores with size greater than 20 νm, not more than 6 for grains number F24 (European Federation of the Manufacturers of Abrasive Products F standard), 2 for grains number F60 and 1 for grains number F100; and b) a tenacity, such as defined in the description, of at least 2.5 Mpa.m1/2 after calcination at 900 °C for 4 hours. The invention is useful for making abrasive tools and refractory parts.</p> |
