Self-resistance electric heating of shaped CFRP laminates: temperature distribution optimization and validation

Abstract

The Self-Resistance Electrical (SRE) heating method to cure carbon fiber reinforced polymer (CFRP) part possesses the advantages of rapid and volumetric heating, low energy consumption, and low asset investment. But the current SRE heating methods are difficult to uniformly cure the shaped CFRP parts due to the non-uniformly distributed Joule heat power in the parts with a varying cross-sectional area. In this paper, an optimized multi-zone SRE heating method is proposed, in which the uniform heating and curing process of the shaped CFRP part is firstly achieved. By optimizing the orientation of the rectangular zones, the local overheating caused by the voltage gradient and current diffusion between different zones is notably suppressed. Combined with the electro-thermal numerical analysis, the influence of the positional offset of electrodes in two adjacent zones on the temperature uniformity is investigated. Based on this, an automated zoning algorithm and the prioritizing method of the zone orientation are established. The proposed method is numerically and experimentally validated with the typical shaped CFRP parts, and the results are compared with that of the existing SRE heating method. The proposed method realizes that the maximum in-plane temperature difference of shaped CFRP parts is reduced by more than 80%. This method significantly improves the temperature uniformity of shaped CFRP parts during the multi-zone SRE heating process, which provides a potential solution for high-quality and efficient curing of CFRP parts.

Effect of carbon nanotubes on thermoset curing and mechanical properties of carbon fiber reinforced epoxy resin laminates fabricated by self‐resistance electric heating

“…However, the CFRP laminates have a strong anisotropic electrical behavior due to inherently high through‐thickness electrical resistivity 23 . As a result, considering the ambient heat dissipation conditions, a large temperature gradient can be generated through thickness during the SRE heating process 24 . Further, some works reported that the SRE‐cured CFRP samples had poorer mechanical performance than those cured by oven heating 25–28 .…”

“…23 As a result, considering the ambient heat dissipation conditions, a large temperature gradient can be generated through thickness during the SRE heating process. 24 Further, some works reported that the SRE-cured CFRP samples had poorer mechanical performance than those cured by oven heating. [25][26][27][28] Thus, it is necessary to find solutions for the SRE heating to uniform the internal Joule heat field and improve the mechanical performance of the SREcured CFRP-laminated components.…”

Characterization of the tensile behavior of continuous carbon fiber reinforced polyamide 6 under self‐resistance electrical heating

“…Self‐resistance electric (SRE) heating, as a novel heating method, efficiently resolves the inadequacies of oven heating by applying the decided electric current to conductive materials to generate joule heat, the materials achieve the desired temperature. This heating process consumes less energy and heats quickly, [ 22 ] which is significantly compatible with the demands of quickly manufacturing. At present, some researchers tried to adopt SRE heating technique to form CFRP composites laminate.…”

Fabrication of continuous carbon fiber reinforced polypropylene composites by injection compression molding with self‐resistance electric heating

“…Self‐resistance electric (SRE) heating, using carbon fiber itself as the inner heat source, provides an alternative solution to the problem of large energy consumption during the fabrication of carbon fiber reinforced plastics (CFRP). [ 28 ] Zhang et al [ 29 ] developed a novel layered SRE curing method to cure thick CFRP laminate, which possessed the superior ability to reduce the through‐thickness temperature difference by 88.46% and save 80.18% of the energy compared with the counterpart of the oven curing process. Wang et al [ 30 ] manufactured carbon fiber reinforced polyamide 6 (CF/PA 6) composites by film stacking technique with SRE heating.…”