Efficient thermal interface materials (TIMs) are urgently needed for heat dissipation of high-power density electronics. In this study, vinyl polydimethylsiloxane (PDMS) composites with the spatial alignment of carbon fibers (CFs) bridged by Al₂O₃ particles were fabricated by the flow field. The through-plane thermal conductivity (TPTC) of the composites with 24 vol% CFs and 47 vol% Al₂O₃ loading reached 38.0 W m⁻¹ K⁻¹. The oriented CFs bridged by Al₂O₃ acted as the efficient through-plane thermal conductive network. Furthermore, the effects of shape factor (b/a), spatial angle (γ) of CFs, and CF loading (V_f) on the TPTC were quantitatively discussed by steady-state finite element simulation combined with micro-computed tomography and machine learning. The positive contribution of the increased V_f to TPTC was in competition with the negative contribution of b/a and γ, both of which increased with the increase of V_f. Moreover, b/a exerted more negative effects than γ. The PDMS composites demonstrated excellent thermal stability (T_d = 407.5 °C, CTE = −55.3 × 10⁻⁶ K⁻¹), low compress modulus (1.71 MPa), and hardness (47 (Shore C)), which made them potential candidates for TIMs. This work offers a feasible method to prepare TIMs on large scale and refreshes the thermal conduction mechanism of TIMs by introducing the influencing factors (b/a and γ).

高功率密度电子产品的散热迫切需要高效的热界面材料 (TIM)。在这项研究中，通过流场制造了由Al ₂ O ₃颗粒桥接的碳纤维（CFs）空间排列的乙烯基聚二甲基硅氧烷（PDMS）复合材料。_{具有24 vol% CFs和47 vol% Al 2} O ₃负载的复合材料的平面热导率(TPTC)达到38.0 W m ^-1  K ^-1。_{由Al 2} O ₃桥接的定向CFs充当有效的平面导热网络。此外，形状因子 ( b/a )、空间角 ( γ) 的 CFs 和 TPTC 上的 CF 载荷 ( V _f ) 通过稳态有限元模拟结合微型计算机断层扫描和机器学习进行了定量讨论。V _f增加对 TPTC 的正贡献与b/a和γ的负贡献竞争，两者都随着V _f的增加而增加。此外，b/a比γ产生更多的负面影响。PDMS复合材料表现出优异的热稳定性（T _d  = 407.5 °C，CTE = -55.3 × 10 ^-6  K ^-1)、低压缩模量 (1.71 MPa) 和硬度 (47 (Shore C))，这使它们成为 TIM 的潜在候选者。这项工作为大规模制备TIMs提供了一种可行的方法，并通过引入影响因素（b/a和γ）刷新了TIMs的热传导机制。