In order to study the influences of mechanical properties on deformation of silicon nitride ceramic penetrator at high temperature, this paper modeled the penetrator which served as calcium carbide reclaiming by using SolidWorks software, coupled and simulated it in Workbench module of Ansys software to analyze the deformation condition of silicon nitride material under different mechanical properties. The results show that the maximum deformation variable of silicon nitride ceramic penetrator at 25 ℃ is 3.12 mm, and the change rate is 0.7%. With the increase of temperature, the deformation of silicon ceramic nitride penetrator decreases. At 1 800 ℃, the maximum deformation is 2.95 mm, and the change rate is 0.6%. The numerical simulation results show that it is feasible to use silicon nitride ceramics as penetrator, which can complete the reclaiming operation of calcium carbide furnace.