Fiber reinforced SiC ceramic helical spring for high elasticity and large deformation at high temperature

Ceramic spring devices play a significant role in mechanical systems, developing advanced ceramic helical spring with combination of high toughness and good elasticity still remains challenging. Herein, C/SiC composite helical springs with good elastic response to temperatures were fabricated by chemical vapor infiltration method. The C/SiC springs with rectangular and circular coil structures show high densities of 2.04 ± 0.162 and 1.96 ± 0.132 g/cm³, respectively. In contrast, C/SiC spring with circular coil structure can achieve high toughness of 0.92 ± 0.004 N/mm and low energy loss of 9.13 × 10⁻³ J at room temperature, while also exhibit an ideal spring constant of 0.35 N/mm and low energy loss of 7.82 × 10⁻² J at 1000°C, which are highly comparable with those reported traditional ceramic springs. Furthermore, through finite element simulations, the stress distribution shows that both springs generate residual stresses at different temperatures after several cycles. The more uniform stress distribution and small irreversible deformation can be responsible for the superior elasticity of C/SiC spring with circular coil structure. The proposed strategy holds promising potential for developing C/SiC composite helical spring for future elastic devices used in complex and extreme service environments.