Abstract: A process for marking a surface of a refractory ceramic part, known as the “surface to be marked.” The part has a microstructure of grains including more than 50% by mass of ZrO2, bound by a silicate binder phase, and a total porosity of less than 5% by volume. The process involves irradiation of the surface with a laser beam. The beam is emitted by a laser device set to comply with relationship: a.V2+b.F2+c.VF+d.V+e.F+f<0, in which: a=104.D+2×106, b=0.5×106.D?150×106, c=0.5×106.D?300×106, d=5×103.D?2.5×106, e=?5×103.D+2.0×106, and f=?5×109.D+1.8×1012. V is expressed in mm/second, D is expressed in mm and F is expressed in kHz.

Abstract: A method for testing the internal structure of a refractory part, has the following steps: a) by a transmission antenna, sending at least one electromagnetic wave, termed a “pulse”, into the refractory part to be tested; b) by a reception antenna, receiving the pulse after reflection thereof by a reflecting zone of the refractory part; c) analyzing the time offset between the two preceding steps in order to deduce the position, in the refractory part, of the reflecting zone, the pulse having a duration less than or equal to 0.5 nanoseconds.

Abstract: A method for testing the internal structure of a refractory part, has the following steps: a) by a transmission antenna, sending at least one electromagnetic wave, termed a “pulse”, into the refractory part to be tested; b) by a reception antenna, receiving the pulse after reflection thereof by a reflecting zone of the refractory part; c) analyzing the time offset between the two preceding steps in order to deduce the position, in the refractory part, of the reflecting zone, the pulse having a duration less than or equal to 0.5 nanoseconds.