composites_qa.csv

Question,Option_A,Option_B,Option_C,Option_D,Answer,Domain,Difficulty,Type,Task,Source
"Rank the following fiber orientations in their ability to achieve both optimum stiffness and strength, with respect to the direction of loading and the micromechanical modeling of short fiber-reinforced composites:1. 90°; 2. 0°; 3. 45°, 4. 30°",1>2>3>4,2 > 4 > 3 > 1,2>4>1>3,3>2>1>4,B,Materials,Easy,Basic Knowledge,Composite Materials Q&A,
Which micromechanical model is most appropriate for analyzing the tensile behavior of composites with randomly oriented short fibers?​,Rule of mixtures,Shear-lag model,Mori-Tanaka model,Halpin-Tsai model,C,Materials,Medium,Basic Knowledge,Composite Materials Q&A,
Rank the following fiber architectures in terms of their effectiveness in enhancing the out-of-plane mechanical properties of composites: 1. Unidirectional fabrics; 2. 2D woven fabrics; 3. 3D braided fabrics,3 > 2 > 1,3>1>2,2>1>3,1>2>3,A,Materials,Easy,Basic Knowledge,Composite Materials Q&A,
What is the primary function of a sizing agent applied to carbon fibers?​,Enhance electrical conductivity,Improve fiber alignment during processing,Promote fiber-matrix adhesion,Reduce fiber cost​ and improve fiber size,C,Materials,Easy,Basic Knowledge,Composite Materials Q&A,
"In the micromechanical modeling of unidirectional ceramic matrix composites, what primary role does the shear-lag model serve?",Predicting fiber pull-out length after catastrophic failure,Describing stress transfer from matrix to fibers through interfacial shear stress,Calculating the chemical degradation of the fiber-matrix interface,Modeling the thermal expansion mismatch between fiber and matrix,B,Materials,Easy,Basic Knowledge,Composite Materials Q&A,
What is the primary purpose of using the Weibull distribution to model fiber strength in composite materials?,To determine the elastic modulus variation of fibers under load,To model the chemical degradation kinetics of fiber surfaces,To statistically describe the variability in fiber strength due to microstructural flaws,To simulate thermal expansion mismatch between fiber and matrix,C,Materials,Medium,Basic Knowledge,Composite Materials Q&A,
Which of the following mechanisms primarily contributes to the formation of a transcrystalline interphase in carbon fiber-reinforced thermoplastic composites?​,Mechanical interlocking,Electrostatic attraction,Heterogeneous nucleation at the fiber surface,Van der Waals interactions​,C,Materials,Medium,Basic Knowledge,Composite Materials Q&A,
Rank the following interfacial bonding mechanisms in order of increasing bond strength in fiber-reinforced composites. 1. Van der Waals forces; 2. Hydrogen bonding; 3. Covalent bonding,1<2<3,2<3<1,2<1<3,3<2<1,A,Materials,Easy,Basic Knowledge,Composite Materials Q&A,
What is the primary effect of moisture absorption on the interfacial shear strength of carbon fiber/epoxy composites?​,"Increase, due to plasticization of the matrix","Decrease, due to hydrolysis at the interface",No significant change,"Increase, due to swelling-induced compressive stresses",B,Materials,Hard,Basic Knowledge,Composite Materials Q&A,
"During hygrothermal exposure, water molecules can hydrolyze polar bonds within the resin near the fiber surface. What chemical mechanism largely contributes to fiber-matrix debonding following long-term moisture exposure?",Acid-catalyzed crosslink densification,Hydrolysis of interfacial functional groups,Oxidation of carbon fibers,Chain scission in the fiber core,B,Materials,Medium,Basic Knowledge,Composite Materials Q&A,
Microcracks or voids created during hygrothermal exposure provide pathways for rapid moisture ingress along the fiber-matrix interface. Which combined mechanical and chemical effect is responsible for accelerating debonding in humid environments?,Capillary suction causing osmotic stress and hydrolytic attack,Moisture-induced matrix stiffening and interfacial shear,Osmotic swelling compressing the fiber and chemically eroding the interface,Thermally induced residual stresses and hydrolysis from moisture cycling,A,Materials,Hard,Basic Knowledge,Composite Materials Q&A,
Which of the following best describes the effect of differential swelling between fiber and matrix due to moisture absorption?​,Enhances interfacial bonding,Leads to microcracking at the interface,Reduces moisture uptake,Improves thermal stability,B,Materials,Hard,Basic Knowledge,Composite Materials Q&A,
"In natural fiber composites, what is a primary cause of fiber-matrix debonding following moisture absorption?",Hydrostatic pressure buildup due to matrix swelling,Fiber swelling causing tensile stresses at the interface,Capillary action leading to fiber erosion,Osmotic pressure drawing fibers closer together,B,Materials,Medium,Basic Knowledge,Composite Materials Q&A,
"In continuous carbon fiber/epoxy composites, water diffusion causes the epoxy matrix to swell. The fibers restrict this expansion, resulting in differential swelling strains. Which stress mechanism primarily leads to fiber-matrix debonding under these conditions?",Hydrostatic stresses in the fibers,Hoop stresses in the matrix perpendicular to fibers,Shear stresses at the fiber-matrix interface,Compressive stresses along fiber direction,C,Materials,Medium,Basic Knowledge,Composite Materials Q&A,
Rank the following fiber packing arrangements in terms of their maximum theoretical fiber volume fraction (from highest to lowest). 1. Hexagonal close-packing; 2. Square packing; 3. Random packing​,2>3>1,3>2>1,1>3>2,1>2>3,D,Materials,Easy,Basic Knowledge,Composite Materials Q&A,
"In unidirectional fiber composites, how does clustering of polygonal-shaped fibers affect the transverse elastic modulus compared to a uniform distribution",It increases the modulus due to enhanced load transfer,It decreases the modulus due to stress concentrations and non-uniform stress distribution,It has no effect on the modulus,It increases the modulus only if the fibers are circular in cross-section,B,Materials,Hard,Basic Knowledge,Composite Materials Q&A,https://doi.org/10.1515/secm-2016-0088
"In the context of composite micromechanical modeling, what is the primary limitation of the Voigt and Reuss models",They require complex numerical simulations,They do not account for the shape and orientation of inclusions,They are only applicable to isotropic materials,They overestimate the effect of the matrix properties,B,Materials,Medium,Basic Knowledge,Composite Materials Q&A,
Which micromechanical model incorporates the concept of an inclusion's eigenstrain to predict effective composite properties?​,Halpin-Tsai model,Mori-Tanaka model,Voigt model,Reuss model,B,Materials,Medium,Basic Knowledge,Composite Materials Q&A,
"In the context of micromechanical modeling, which method is particularly suitable for composites with periodic microstructures, such as woven fabrics?​",Voigt model,Mori-Tanaka model,Method of cells,Reuss model,C,Materials,Medium,Basic Knowledge,Composite Materials Q&A,
Rank the following micromechanical models based on their suitability for modeling composites with high inclusion concentrations. 1. Voigt/Reuss models; 2. Mori-Tanaka model; 3. Method of cells,2>1>3,1>2>3,3>2>1,3>1>2,C,Materials,Medium,Basic Knowledge,Composite Materials Q&A,
A carbon fiber composite sample undergoes Mode I dominant interfacial fracture testing. The interfacial fracture energy is a critical parameter for durability. Which of the following factors does not directly influence the interfacial fracture energy?,Fiber surface roughness and chemistry,Matrix crosslink density,Fiber elastic modulus,Presence of residual thermal stresses,C,Materials,Hard,Basic Knowledge,Composite Materials Q&A,
"A carbon fiber/epoxy laminate is fabricated with a [0°/±45°/90°] layup. The goal is to maximize in-plane shear stiffness, while maintaining tensile strength. Rank the fiber orientations by their contribution to in-plane shear modulus, from highest to lowest. 1. 0° fibers; 2. ±45° fibers; 3. 90° fibers",1>3>2,3>2>1,1>2>3,2>1>3,D,Materials,Medium,Basic Knowledge,Composite Materials Q&A,