The UV durability of carbon fiber composites has been a concern. In this work, irradiation on fiber-reinforced polymer (CFRP) materials was performed using an artificial accelerated aging chamber to investigate the effect exposure composites. caused some macromolecular chains surface resin break, resulting in loss small molecules and mass. After 80 days exposure, significant decline macroscopic mechanical properties occurred longitudinal direction, with largest decrease 23% compressive...

Abstract Short fiber reinforced polymers (SFRP) based on unidirectionally arrayed chopped strands (UACS) offer exceptional formability and great mechanical properties. To ensure its stability safety in applications, it is crucial to enhance the impact performance of UACS laminates. This study investigated low‐velocity (LVI) responses damage evolution laminates with different slit sizes continuous carbon polymer (CFRP) under various energies (4, 7, 11 J). The curves force energy were recorded...

Impact damage in carbon fiber reinforced polymer (CFRP) laminates threatens the safety of their structures, making it necessary to perform non-destructive testing (NDT) avoid catastrophic accidents. In this paper, TOF-based fuzzy C-means (FCM) clustering method was proposed for tomographic evaluation impact damages CFRP laminates. Ultrasound water immersion experiments were conducted obtain time-of-flight (TOF) features with different energies. To limitations common FCM methods such as...

To develop liner materials with improved toughness, this study combines molecular dynamics simulations and experimental testing to investigate the effect of different mass ratios (10/0, 7/3, 6/4, 4/6, 3/7, 0/10) high-density polyethylene (HDPE)/polyamide 6 (PA6) on their fracture toughness composites. The was quantitatively assessed using J-integral method, while material’s behavior in terms crack propagation during tensile deformation examined at level. results reveal that as HDPE ratio...

Short-fiber-reinforced polymers (SFRPs) based on unidirectionally arrayed chopped strands (UACSs) have excellent formability and outstanding mechanical response. The low-velocity impact response, such as the delamination, damage tolerance energy absorption of UACS composites, are essential to guarantee stability safety composite components in service. current study investigates response continuous carbon-fiber-reinforced polymer (CFRP) laminates with vertical slits under drop-weight various...

This paper derives simple and explicit formulas for computing the parameters of Thevenin's equivalent circuit model a discharging battery. The general has n pairs parallel resistors capacitors ( nth-order model). main idea behind new method is to transform problem solving system high-order polynomial equations into one several linear single-variable equation, via some change variables. computation can be implemented with MATLAB code less than half-page long. Experimental computational...

Progressive damage models based on continuum mechanics are used in combination with cohesive elements to explore the effect of three different failure criteria including Chang-Chang, Hashin and Puck criteria, structural response mechanisms composite laminates subjected low-velocity impact. Three evolution laws equivalent strain for intralaminar models, delamination is simulated by bilinear model quadratic criteria. A new numerical optimization method combining analytical approximation Golden...

In this present paper, a novel method was proposed to extract the equi-biaxial residual stress, yield strength and strain hardening exponent of metal materials from load-displacement curve by continuous spherical indentation test. A representative independent on introduced establish relationship between material properties parameters dimensional analysis. The dimensionless function at different penetration depths were determined through analyzing results obtained finite element (FE)...

P91 steel is a typical used in the manufacture of boilers ultra-supercritical power plants and heat exchangers nuclear plants. For long-term serviced pressurized structures, main failure mode welded joint failure, especially affected zone (HAZ) failure. Repair welding technique an effective method for repairing such local defects. However, thermal shock composed high temperature stress repair process will pose critical loading condition existing defects near source which cannot be detected...

An ammonium polyphosphate (APP) surface-modified by silane coupling agent was used as flame retardant in high-impact polystyrene (HIPS). A series of HIPS nanocomposites containing different mass fractions APP (k-APP) (3-aminopropyl triethoxysilane, KH 550) and carboxylic-functionalized MWCNTs (COOH⁻MWCNTs) were prepared the melt blending method. composite only also a reference material. Scanning electron microscopy (SEM) employed to investigate dispersion fillers into matrix, it found...

Metal parts formed by laser additive manufacturing methods usually have large surface roughness, which affects the corrosion resistance of parts. This study reported reason for and mechanism roughness 316L stainless steel samples manufactured selective melting (SLM) at different build angles. Through study, top (average is 15.3 μm) due to molten channel structure on surface. The side 19.1 incomplete fused particles adhering electrochemical experiments, influence angle polishing treatment...

This paper characterizes laser-generated guided waves in a metal-lined composite-overwrapped pressure vessel (COPV) to assess typical damage, including interfacial debonding and low-velocity impact damage. First, an eigenfrequency approach that avoids additional coding is utilized theoretically analyze the dispersion characteristics of COPV. The theoretical results show significantly alters curves, wavenumber L(0, 1) mode sensitive Experimental verifications were conducted based on full...

Based on the statistical analysis from a great deal of failure cases, generally, causes buried pipeline can be classified into four factors, namely, third-party damage, erosion–corrosion design and construction error, incorrect operation. The factors influencing are complicated, varied fuzzy. Especially, influence damage character fuzziness, which difficult to express with accurate mathematic models. In this paper, gas first analyzed by fault tree method. Then, likelihood consequence, two...

There is limited research on the fracture toughness of carbon-fiber-reinforced polymer (CFRP) materials under accelerated UV aging conditions. In this study, primary focus was investigating influence varying durations ultraviolet (UV) irradiation at different temperatures Mode I, II, and mixed-mode CFRP laminates. The results indicate that with increasing duration, material’s I increases, while II significantly decreases. exhibits an initial increase followed by a subsequent decrease....

Abstract Although lightweight fiber‐reinforced polymer (FRP) composites are widely used in various engineering fields due to their high specific strength and modulus, the mutual exclusion of toughness is one bottlenecks field FRP design because inherent brittleness fiber themselves. In this research, discontinuous structures with vertical bi‐angled slits introduced into thin‐ply carbon prepreg. The fracture energy delamination degree center layer could be controlled by adjusting structural...