Effective Thermal/Mechanical Properties of Honeycomb Core Panels for Hot Structure Applications

Online Guided Wave-Based Debonding Detection in Honeycomb Sandwich Structures

“…= filtered guided wave signals from specimens without debonding in the frequency domain F d = filtered guided wave signals from specimens with debonding in the frequency domain f = frequency f c = central frequency f 1 = low cutoff frequency of the guided wave signal f 2 = high cutoff frequency of the guided wave signal Ht = Heaviside step function l ij = distance between the actuator #i and sensor #j P d = damage localization probability of arbitrary position x; y within the sensor network P ij = damage distribution probability estimated from the actuator-sensor pair #i; #j SDC ij = signal difference coefficient from the actuator-sensor pair #i; #j t = time V = amplitude of the excitation signal = scaling parameter ! 1 = lower limit of the narrowband excitation frequency ! 2 = upper limit of the narrowband excitation frequency I.…”

“…2 = upper limit of the narrowband excitation frequency I. Introduction D UE to attractive characteristics such as high strength/stiffnessto-weight ratios and effective acoustic insulation, honeycomb sandwich structures have been used extensively in marine, aerospace, and aeronautic industries [1,2]. However, an intensive load or repeating loading in the core tends to induce debonding along the skin-core interface, threatening the integrity and safety of the whole structure [3].…”

Ultrasonic Lamb wave‐based debonding monitoring of advanced honeycomb sandwich composite structures

“…Aramid honeycomb composite sandwich panel (AHCSP) is one of the advanced sandwich composite structures, in which thin composite/metallic face‐sheets (skins) are bonded with adhesive to a relatively thick and extremely lightweight aramid honeycomb core . The AHCSPs offers many referred advantages such as high strength‐to‐weight ratio, fire resistant (self‐extinguishing), corrosion resistant, thermally insulating, excellent dielectric properties, excellent creep and fatigue performance, good thermal stability, overexpanded cell configuration suitable for forming simple curves, and compatible with most adhesives . But due to improper handling, manufacturing defects, ageing, and repeated loadings, debondings often occur at the bonded interphase between the face‐sheet and core in these structures .…”

Wave Propagation in Aluminum Honeycomb Plate and Debonding Detection Using Scanning Laser Vibrometer

“…In comparison with isotropic aluminum materials, a notable advantage of aluminum sandwich plates is their high strength-to-weight ratio, which provides an efficient mechanism for resisting bending and buckling loads [ 1 , 2 ]. Because of its lightweight yet strong property, the honeycomb sandwich structure (HSS) is one of the most common sandwich structures used in marine, aerospace, and aeronautic industries [ 3 , 4 ]. Nevertheless, as a result of its inherent weakness in terms of adhesive bonding, both intensive and cyclic loads on HSSs can introduce debondings along the skin-core interfaces, substantially compromising its strength and stiffness [ 5 ].…”