Title: Crash Performance of Epoxy-Polyamide Hybrid Composites

Authors: Diana G. Heflin, Alex Reichanadter, Jan-Anders E. Mansson

DOI: 10.33599/nasampe/c.22.0179

Abstract: Epoxy-matrix composites are widely used in high-performance applications where their relatively high specific strength and stiffness is advantageous, but often less performant in impact applications. Thermoplastic materials, such as polyamide, can be added to the epoxy-matrix composites to improve energy absorption by different deformation and crack deviation mechanisms. Introduction of neat thermoplastics into epoxy-based composites may reduce part strength and stiffness particularly when occupying extensive volume fractions of the higher performance epoxy composites, so using fiber-reinforced thermoplastics can improve part toughness without sacrificing strength and stiffness. In this study, hybrid composites were made from epoxy/carbon fiber and polyamide/carbon fiber plates. The bond strength at the epoxy-polyamide interface was altered via a change in processing temperature during the compression molding process. Because no additional materials or processing steps were introduced, this method of improving adhesion is viable for existing manufacturing processes that cannot support increases in cost or cycle time. This study examined the effect of the epoxy-polyamide interfacial bond strength and part/impact orientation on the low-velocity impact performance of hybrid composites. Dent depth and absorbed energy were recorded for impact samples, and performance was compared to quasi-static indentation testing undertaken on the same material. Impact damage area was assessed non-destructively using X-Ray microscopy, and a projected damage area was calculated. A stronger epoxy-polyamide interfacial bond was shown to improve the energy absorption and reduce impact damage. Further, part orientation had a notable effect on crash performance, and should be carefully selected based on the desired application.

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Conference: CAMX 2022

Publication Date: 2022/10/17

SKU: TP22-0000000179

Pages: 13

Price: $26.00