Weibull statistical analysis of flexure breaking performance for alumina ceramic disks sintered by solar radiation heating

Densified alumina ceramic disk specimens were prepared through sintering co mpacted alumina powders by concentrated solar beam in inert Ar gas atmosphe re and their flexure breaking behaviour was evaluated by the ring-on-ring j ig test under application of equibiaxial stress. Slope m of Weibull plot fo r MOR (modulus of rupture) values of these specimens was comparable to that of the reference alumina disk specimens prepared by sintering in an electr ic furnace under comparable conditions (1600 degrees C for 30 min) whereas mean MOR level of the former was slightly lower than that of the latter. Th us, the failure mechanism of the specimens sintered by solar radiation heat ing and that of the specimens sintered in the electric furnace were conclud ed to be practically indistinguishable. This evidence guarantees that alumi na ceramic sintered bodies, with quality comparable to those obtained throu gh traditional sintering process, can be prepared by solar heating in spite of quite fast rate of heating and cooling realised in the solar furnace. ( C) 2000 Elsevier Science Ltd and Techna S.r.l. All rights reserved.