Hybrid Connection: The method of combining bonding and mechanical connection.

Curing: The process where resin undergoes a cross-linking reaction through heating or with curing agents, transforming from soft to hard solidified material.

Cocuring: The method of joining two carbon fiber composite components by curing them simultaneously.

Curing Temperature: The temperature at which the curing reaction occurs.

Low-Temperature Curing: Generally refers to curing at 60-80℃.

Medium-Temperature Curing: Generally refers to curing at 120-130℃.

High-Temperature Curing: Generally refers to curing above 150℃.

Aging: The process during which polymer materials undergo a series of changes in their chemical composition and structure due to the combined effects of environmental factors such as heat, oxygen, water, light, microorganisms, and chemical media. These changes can result in physical property deterioration such as hardening, stickiness, brittleness, discoloration, and loss of strength.

Lamination: The process of stacking composite materials layer by layer from unidirectional sheets.

Structural Component: A component used to bear loads, termed as a structural component.

Laminate: The basic structural unit of continuous fiber composite materials.

Laminated Plate: A composite plate formed by stacking laminate sheets layer by layer.

Layer Angle: The angle between the unidirectional fiber layer direction and the main axis direction of the composite material.

Layer Proportion: The ratio of the number of fiber layers in a specific direction to the total number of layers.

Stiffened Panel: In structural design, stiffening ribs are used in a direction perpendicular to the panel to enhance the load-bearing capacity of the panel and the overall structure. Stiffening ribs and panels can be part of an integral structure or connected by bonding or welding.

Glass Transition Temperature: The temperature corresponding to the transition from a high elastic state to a glassy state or vice versa.

Interface: Generally refers to the bonding region between carbon fiber and the matrix.

Delamination: The phenomenon where layers separate due to weak interlaminar strength when a laminated plate is subjected to force.

Vacuum Bag Molding: A molding method where a plastic bag film is used to apply fluid pressure to uniformly press a reinforced plastic placed between a rigid mold and an elastic bag, forming the part.

Autoclave: A cylindrical pressure vessel, commonly used to provide necessary heat and pressure for compacting and curing advanced composite material parts.

Compression Molding: The process of placing fibrous plastic into a mold cavity at molding temperature, then closing the mold and applying pressure to shape and cure it.

RTM: Resin Transfer Molding (RTM) is a molding method where resin is transferred into a mold to manufacture aerospace advanced composite materials at low cost.

Wet Compression Molding: A molding method where resin is sprayed onto the surface of layered fibers, placed in a mold, and the mold is sent to a press. The resin impregnates the fibers and cures through mold closure.

Hand Lay-Up Molding: Also known as contact molding, this process involves manually placing alternating layers of carbon fiber fabric and resin on a mold, which is then cured to form carbon fiber products.

Filament Winding: A process where continuous fibers (or cloth tapes, prepreg yarns) impregnated with resin are wound onto a mandrel according to a certain pattern, then cured and demolded to obtain the product.

Pultrusion Molding: A method where continuous fibers or their fabrics are impregnated with resin and then passed through a heated forming die to cure the resin, producing composite profiles.

SMC: Sheet Molding Compound, an intermediate material in composites, primarily made from SMC-specific yarn, unsaturated resin, low-shrink additives, fillers, and various additives.

BMC: Bulk Molding Compound, a semi-dry method for manufacturing glass fiber reinforced thermosetting products.

Gelcoat: A composite material surface coating formed by adding pigments and thixotropic agents to unsaturated polyester (UP) used for coloring and creating thixotropic properties.

Resin-Starved Area: The phenomenon where the resin-to-fiber ratio is imbalanced, resulting in resin-deficient areas. Severe resin starvation exposes fibers, preventing them from forming an integrated structure and protecting them with the resin matrix, impacting the composite material's load-bearing capacity and structural integrity.

Principal Axis: The main fiber direction in composites.

Off-Axis: Directions in composites that form an angle with the principal axis.

Stress-Strain Curve: A curve representing the deformation of a material under stress, with strain as the horizontal coordinate and applied stress as the vertical coordinate.

Micromechanics: A method for analyzing the properties and interfacial conditions of carbon fibers and resin in composites.

Macromechanics: A method in composite mechanics that uses laminated plate theory for analysis, treating the fibers and resin matrix as a whole without distinction within each layer.

Failure Criterion: A standard used to determine whether a composite material has failed.

Residual Stress: Self-balanced internal stress remaining in a material after the removal of external forces or non-uniform temperature fields.

Safety Factor: A coefficient used in engineering structural design to reflect the safety level of a structure. Determining the safety factor involves considering various uncertainties such as load, material mechanical properties, differences between test values and design values, calculation models, and construction quality.

Allowable Value: A characteristic value of composite mechanical properties with a certain confidence level and reliability, determined from sample test data and statistical analysis under specified load types and environmental conditions.

A-Basis Value: A mechanical property limit value where 99% of the performance is above this value with 95% confidence.

B-Basis Value: A mechanical property limit value where 90% of the performance is above this value with 95% confidence.

S-Basis Value: A mechanical property value usually specified by relevant government regulations as the minimum value for materials.

Typical Value: The average value obtained from valid test results of at least five samples.

Interlaminar Shear: The force acting between the layers of laminated composites, causing strain along the interface. The maximum shear stress that composites can withstand along the interlaminar direction is termed interlaminar shear strength, usually used to evaluate the bond strength between fibers and the matrix.

Damage Tolerance: The ability of a structure to resist defects, cracks, wear, and foreign object damage within a specified maintenance cycle.

Building-Block Validation: A low-risk, low-cost composite structure design and validation technology that combines tests and analysis, incrementally increasing specimen size, test scale, and environmental complexity while reducing quantity, using the results of one stage to support the next stage.

Sample: A small laminated plate test piece used to determine the characteristics of basic layers, laminated plates, or general structures.

Element: A common part of a complex structure, such as skins, stringers, and shear webs.

Assembly: A larger three-dimensional structure that can represent part of the overall structure, such as beam sections, wall panels, and wing boxes.

Simulation: The method of using finite element analysis on a computer to calculate the damage and deformation of composite components.

Damage Resistance: A parameter indicating the ability of standard composites to resist damage propagation.

C/C Composite: Carbon fiber reinforced carbon matrix composites.

Impact Damage: Damage generated in composites under impact loads.