Characterization of anisotropic electrical conductivity of carbon fiber composite materials by a microwave probe pumping technique

Abstract

Characterization of anisotropic conductivity of thin carbon fiber/poly ether ether ketone (PEEK) composite was investigated by noncontact and nondestructive microwave probe pumping (MPP) technique. The microwave was pumped by a coaxial probe, and the pumped field intensity distribution was measured by a near-field scanning microwave microprobe (NSMM) and a thermography camera. From the measurement and simulation results, it was observed that intensity of the electromagnetic field was higher along the high conductive directions due to the larger eddy current along these directions. Additionally, electrical defect detection by pumping probe technique was investigated. It was observed that the field intensity drastically decreased around the electrical defect. We showed that through an anisotropic field distribution around the pumping probe, an electrical defect of a carbon fiber/PEEK composite can be detected by combination of MPP and NSMM techniques.

Radio-Frequency Conductivity Characteristics and Corresponding Mechanism of Graphene/Copper Multilayer Structures

“…Hanju Lee’s research suggests that in an RF field, the presence of defects within a material leads to significantly higher electric and magnetic field strengths near the defect compared to regions without defects, indicating an inhomogeneity of electric and magnetic fields. This inhomogeneity results in the accumulation of charges or dipoles, referred to as defect dipoles [ 39 ]. The impact of defective dipoles on the properties of various materials has been extensively investigated.…”

Boosting electromagnetic wave absorption of Ti 3AlC 2 by improving effective electrical conductivity

“…For n = 2, it can be seen from Figs. 3(a) and 3(b) that when electric field directions are horizontal and vertical, respectively, the current density distribution is entirely different, indicating that the electrical conductivity of the Ti 3 AlC 2 particles within two grains has a strong anisotropy [43]. For the cases where n are 100 and 200, the current density difference decreases, while the direction of the applied electric field is changed, i.e., the anisotropy of the electrical conductivity is reduced.…”

A Review of Microwave Thermography Nondestructive Testing and Evaluation

“…Furthermore, the subsequent thermal imaging is directly affected by rapid and uniform heating. British and Polish researchers have investigated waveguides as excitation modules [ 57 , 72 ]; French scholars have studied the pyramidal horn antenna as an excitation module [ 56 ]; South Korean scholars have studied the coaxial setup as excitation module [ 69 ]. However, the advantages and disadvantages of these microwave excitation modules are not thoroughly studied, which results in is it being difficult to achieve the optimal detection ability with MWT systems.…”

“…Lee et al proposed a microwave probe pumping technique to characterize the anisotropic electrical conductivity in carbon-fiber composite materials [ 69 ]. They used CST Microwave Studio to investigate the electromagnetic field distribution with different anisotropic conductivity.…”