Composites (Simple Bounds) model parameters

The Composites (Simple Bounds) model predicts the performance of continuous fiber-reinforced and particulate-filled composites. These materials, which generally exhibit high specific strength and stiffness values, are frequently used in structural components in weight-critical applications.

In principle any two or more materials can be combined to produce a composite. In general terms, this involves adding a reinforcing filler, which may be in the form of continuous fibers, chopped fibers or particulates, to a matrix that forms a binding continuum around the filler. The aim in creating this type of structure is to utilize the benefits of both materials. For example, glass fiber reinforced plastic (GFRP) materials combine the high strength and stiffness of glass fibers with the toughness of a polymer matrix.

There are three types of Composite (Simple Bounds) model:
  • Continuous fiber (UD & QI)
  • Particulate
  • Short fiber
The model types within the Composite (Simple Bounds) model allow the upper and lower bounds in performance of two-component composite systems (one reinforcement and one filler) to be readily predicted and compared with conventional materials.
Composite model types: Unidirectional (Continuous UD); Laminates (Continuous QI); Chopped fiber and Particulate.
Section Parameter Description
Fiber orientation How fibers are arranged:
  • For Continuous Fiber (UD & QI), select from Unidirectional or Quasi-isotropic
  • For Short Fiber Composites, select between Aligned or Random
Source Records Matrix Set the material record for the bulk material.
Fiber Set the material record for the reinforcement fiber.
Note: The performance of particulates and fibers are frequently higher than the properties of the associated bulk material. As a result it is important, where appropriate, to select materials for the reinforcement from the 'Fibers and particulates' MaterialUniverse folder.
Model variables Fiber volume fraction The reinforcement Fiber volume fraction for the composite. You can enter a single value, list, or range. Specifying a list or range enables a family of composites to be evaluated.
Note: The maximum reinforcement volume fraction that can be realistically achieved is 70%, hence this is the upper bound that a user can specify.
Number of values When a range is specified, the number of volume fractions must also be specified.
Model Parameters Fiber aspect ratio (s) Only applies to Short fiber composites. Where (s = fiber length / fiber diameter). The default value is 50.
Record Naming Matrix An abbreviated name, used to create the record names for the new composite materials.
Fiber An abbreviated name, used to create the record names for the new composite materials.
Values quoted on datasheet are for equivalent properties. The Notes section contains information on constituent materials and model configuration. Cannot be specified in selection projects.