The resistance to ablation of a ceramic nozzle made of a 50 vol% Carbon fiber-50 vol% ZrB2 composite was evaluated in a high velocity oxy-fuel torch (HVOF) in conditions simulating typical exhaust engine flows. The composite was prepared by hot pressing a mixture of ZrB2 powders and C chopped fibers and characterized in terms of microstructural features, strength and toughness. Then, the sintered pellet was machined by electro-discharge machining to obtain a ceramic throat. The throat was assembled to convergent and divergent graphite parts to compose a segmented nozzle and tested in HVOF torch under a heat flux of 2.5 MW/m2 and flame temperature of 2730 K. Fluid dynamic simulations enabled to rebuild the heat field temperatures of the jet flow and of the solid nozzle. The throat well survived 30 s undergoing little oxidation of the frontal zone without dimension or shape variation. No appreciable ablation of the throat was measured.
Design, fabrication and high velocity oxy-fuel torch tests of a Cf-ZrB2- fiber nozzle to evaluate its potential in rocket motors / Sciti, D.; Zoli, L.; Silvestroni, L.; Cecere, Anselmo; DI MARTINO, GIUSEPPE DANIELE; Savino, Raffaele. - In: MATERIALS & DESIGN. - ISSN 1873-4197. - 109:5 November 2016(2016), pp. 709-717. [10.1016/j.matdes.2016.07.090]
Design, fabrication and high velocity oxy-fuel torch tests of a Cf-ZrB2- fiber nozzle to evaluate its potential in rocket motors
CECERE, ANSELMO;DI MARTINO, GIUSEPPE DANIELE;SAVINO, RAFFAELE
2016
Abstract
The resistance to ablation of a ceramic nozzle made of a 50 vol% Carbon fiber-50 vol% ZrB2 composite was evaluated in a high velocity oxy-fuel torch (HVOF) in conditions simulating typical exhaust engine flows. The composite was prepared by hot pressing a mixture of ZrB2 powders and C chopped fibers and characterized in terms of microstructural features, strength and toughness. Then, the sintered pellet was machined by electro-discharge machining to obtain a ceramic throat. The throat was assembled to convergent and divergent graphite parts to compose a segmented nozzle and tested in HVOF torch under a heat flux of 2.5 MW/m2 and flame temperature of 2730 K. Fluid dynamic simulations enabled to rebuild the heat field temperatures of the jet flow and of the solid nozzle. The throat well survived 30 s undergoing little oxidation of the frontal zone without dimension or shape variation. No appreciable ablation of the throat was measured.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
