Effect of Sintering Pressure on Microstructure and Properties of Al⁃0.6Si Composite Materials

doi:10.12422/j.issn.1672-6952.2026.05.009

Abstract

Abstract:

Spark plasma sintering is a rapid, low⁃temperature, high⁃density sintering technique that facilitates the fabrication of dense compacts while mitigating excessive grain growth and insufficient densification. This study systematically investigated the effects of sintering pressure on the microstructure and thermophysical properties of Al⁃0.6Si composites prepared by spark plasma sintering. The results show that sintering pressure strongly influences the properties of high⁃silicon aluminum composites. At a sintering pressure of 40 MPa, the Al⁃0.6Si composite exhibits the densest microstructure and the smallest average silicon⁃phase size. Its thermal conductivity is 130.35 W/(m·K), thermal expansion coefficient is 8.51×10⁻⁶ K⁻¹, Vickers hardness is 329.2 HV, density is 2.394 3 g/cm³, and relative density reaches 96.93%. These results demonstrate that optimizing the sintering pressure is an effective route to preparing high⁃performance composites for electronic packaging and provides process guidance for their fabrication.

Key words: Electronic packaging materials, Al?0.6Si, Sintering pressure, Spark plasma sintering, Thermal?physical properties

摘要：

放电等离子烧结是一种快速、低温的烧结工艺，可制备高密度烧结体，解决晶粒尺寸过大、密度偏低的问题。系统探讨了通过放电等离子烧结工艺制备Al⁃0.6Si复合材料时烧结压力对复合材料微观结构及热物理性能的影响。结果表明，烧结压力对高硅铝复合材料的物理性能起至关重要的作用；当放电等离子烧结压力为40 MPa时，Al⁃0.6Si复合材料具有最致密的微观结构，且Si相的平均尺寸最小；该材料的热导率为130.35 W/（m·K），热膨胀系数为8.51×10-6 K-1，维氏硬度为329.2 HV，密度为2.394 3 g/cm3，相对密度达到96.93%。由此可知，基于理论依据和工艺指导，优化烧结压力可制备出适用于电子封装领域的高性能复合材料。

关键词: 电子封装材料, Al?0.6Si, 烧结压力, 放电等离子烧结, 热物理性能

CLC Number:

TF821

Li LI, Xingjun Gao, Zilong DENG, Jianqi XU, Bo LI. Effect of Sintering Pressure on Microstructure and Properties of Al⁃0.6Si Composite Materials[J]. Journal of Liaoning Petrochemical University, 2026, 46(5): 61-67.

李利, 高兴军, 邓子龙, 徐建琪, 李博. 烧结压力对Al⁃0.6Si复合材料组织及性能的影响[J]. 辽宁石油化工大学学报, 2026, 46(5): 61-67.

Figures/Tables 7

Fig.1 Morphology and particle size distribution of Al and Si powders

Fig.2 Microstructure of Al?0.6Si prepared under different sintering pressures

Fig.3 Microstructure of Al?0.6Si prepared under different sintering pressures after SPS treatment

Fig.4 Average silicon phase size of Al?0.6Si prepared under different sintering pressures

Fig.5 TEM images of the Al?Si interface inside Al?0.6Si prepared under different sintering pressures

Fig.6 The effect of sintering pressure on the thermal conductivity and thermal expansion coefficient of Al?0.6Si

Fig.7 The effect of sintering pressure on the relative density, density, and hardness of Al?0.6Si

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