锥台嵌挤SiC陶瓷预应力影响因素研究

Study on factors influencing prestress distribution in truncated-cone-interlocked SiC ceramics

  • 摘要: 钢环约束和预应力围压能够显著改善陶瓷材料的抗侵彻性能,但现有预应力技术因复杂性或低效性难以在工程中广泛应用。基于锥台嵌挤的简易方法,通过锥面配合契紧的方式对锥台形碳化硅(SiC)陶瓷施加径向预应力,以陶瓷下压深度以及压入力大小等指标控制预应力水平。采用试验、数值模拟与理论分析相结合的方法,研究盈差、钢环壁厚及材料强度等因素对SiC陶瓷和钢约束环中预应力分布规律的影响。结果表明,锥台状SiC陶瓷压入钢环过程中,陶瓷预应力大小随盈差的增加近似呈线性增加,当应力超过约束钢环本身的屈服强度时,陶瓷预应力并未出现衰减,而是保持了相对稳定的预应力水平,基于此,可以适当放宽钢环和陶瓷靶的加工误差容许值,降低工件的加工成本;钢环强度越高,能够为陶瓷提供的预应力潜力越大,钢环的材料利用率也会提高;当盈差保持不变时,尽管增加钢环壁厚可以有效提高陶瓷预应力水平,结构中的抗侵彻薄弱环节也随之增多;基于试验验证的数值模型能较为准确的反映陶瓷和钢环的预应力分布规律,理论公式可以较为准确的预测弹性阶段钢环对陶瓷施加的预应力,为实际工程应用提供有益参考。

     

    Abstract: Steel ring confinement and prestress can significantly enhance the penetration resistance of ceramic materials. However, existing prestress techniques face limited engineering application due to their complexity and inefficiency. This study introduced a simplified truncated-cone-interlocking method that applies radial prestress to silicon carbide (SiC) ceramics through conical surface engagement. Prestress levels were controlled by ceramic insertion depth and pressing force. Integrated experimental, numerical simulations, and theoretical analysis approaches were employed to investigate the effects of interference fit, steel ring wall thickness, and material strength on prestress distribution in SiC ceramics and steel rings. Results showed that ceramic prestress increased nearly linearly with interference fit. Prestress remained stable even when stress exceeded the yield strength of steel rings. This allows relaxed machining tolerances for steel rings and ceramic targets, reducing production costs. Higher steel ring strength increases prestress potential and material utilization efficiency. When interference fit is constant, thicker steel ring walls raise ceramic prestress but introduce more weak points in penetration resistance. A validated numerical model accurately reflects prestress distribution in ceramics and steel rings. A theoretical formula precisely predicts prestress in the elastic stage, providing valuable guidance for engineering applications.

     

/

返回文章
返回