Material properties - A150
|Foundational knowledge article|
Overview[edit | edit source]
A material property is an attribute of a material expressed in terms of its measured response to specific imposed stimulus . For example, an elastic modulus is a property that defines a material’s deformation response to imposed forces. Material property definitions are independent of shape and size of the material. When selecting a material, it is a specific set of attributes (material properties) of a material that a designer seeks .
Material properties may be dependent on the specific direction of measurement. Properties that are measured the same in all directions, therefore independent of direction, are referred to as isotropic. Properties dependent on the axis direction of measurement are referred to as anisotropic or non-isotropic.
The included pages of material properties will expand in time to complement the future content growth of the KPC and its resource of topics.
Basic Definitions of Material Properties[edit | edit source]
Link to main Basic Definitions of Materials Properties page
In the Knowledge in Practice Centre (KPC), general material properties are defined as properties that apply to all material classes – properties applying to all materials, and not necessarily specific to only polymer matrix composites or their individual constituent material components.
Click on one of the example properties listed below, or visit the general material properties page for more properties.
Basic Definitions of Material Properties
Some examples of basic material properties include:
Polymer Properties[edit | edit source]
Link to main Polymer Properties page
In the Knowledge in Practice Centre (KPC), polymer properties are defined as properties that are unique attributes to polymer materials.
Click on one of the example properties listed below, or visit the polymer properties page for more properties.
Some examples of polymer properties include:
Reinforcement Properties[edit | edit source]
Link to main Reinforcement Properties page
In the Knowledge in Practice Centre (KPC), reinforcement properties are defined as properties that are describing the composite reinforcement material.
Some examples of reinforcement properties include:
- Surface reactivity (effect of sizing)
- Surface area
- Yield and fracture
Click here to explore reinforcement properties.
Composite Properties[edit | edit source]
Link to main Composite Properties page
In the Knowledge in Practice Centre (KPC), composite properties are defined as properties that are describing the combined composite material.
Click on one of the example properties listed below, or visit the composite properties page for more properties.
Some examples of composite material properties include:
- Heat of reaction (composite)
- Specific heat capacity (composite)
- Viscosity (composite)
Property Measurement[edit | edit source]
For methods to obtain material property values, please see the Foundational Methods Documents page.
Link to Foundational Method Documents page
Explore this area further
- Material properties - A150
- Basic Definitions of Material Properties - A211
- Polymer properties - A212
- Reinforcement properties - A213
- Composite properties - A214
- ↑ [Ref] Callister, William D. (2003). Materials Science and Engineering: An Introduction. John Wiley & Sons, Inc. ISBN 0-471-13576-3.CS1 maint: uses authors parameter (link) CS1 maint: date and year (link)
- ↑ [Ref] Ashby, M.F. (2011). Materials Selection in Mechanical Design. Elsevier. doi:10.1016/C2009-0-25539-5. ISBN 9781856176637.CS1 maint: uses authors parameter (link) CS1 maint: date and year (link)
Welcome to the CKN Knowledge in Practice Centre (KPC). The KPC is a resource for learning and applying scientific knowledge to the practice of composites manufacturing. As you navigate around the KPC, refer back to the information on this right-hand pane as a resource for understanding the intricacies of composites processing and why the KPC is laid out in the way that it is. The following video explains the KPC approach:
Understanding Composites Processing
The Knowledge in Practice Centre (KPC) is centered around a structured method of thinking about composite material manufacturing. From the top down, the heirarchy consists of:
- The factory
- Factory cells and/or the factory layout
- Process steps (embodied in the factory process flow) consisting of:
The way that the material, shape, tooling & consumables and equipment (abbreviated as MSTE) interact with each other during a process step is critical to the outcome of the manufacturing step, and ultimately critical to the quality of the finished part. The interactions between MSTE during a process step can be numerous and complex, but the Knowledge in Practice Centre aims to make you aware of these interactions, understand how one parameter affects another, and understand how to analyze the problem using a systems based approach. Using this approach, the factory can then be developed with a complete understanding and control of all interactions.
Interrelationship of Function, Shape, Material & Process
Design for manufacturing is critical to ensuring the producibility of a part. Trouble arises when it is considered too late or not at all in the design process. Conversely, process design (controlling the interactions between shape, material, tooling & consumables and equipment to achieve a desired outcome) must always consider the shape and material of the part. Ashby has developed and popularized the approach linking design (function) to the choice of material and shape, which influence the process selected and vice versa, as shown below:
Within the Knowledge in Practice Centre the same methodology is applied but the process is more fully defined by also explicitly calling out the equipment and tooling & consumables. Note that in common usage, a process which consists of many steps can be arbitrarily defined by just one step, e.g. "spray-up". Though convenient, this can be misleading.
The KPC's Practice and Case Study volumes consist of three types of workflows:
- Development - Analyzing the interactions between MSTE in the process steps to make decisions on processing parameters and understanding how the process steps and factory cells fit within the factory.
- Troubleshooting - Guiding you to possible causes of processing issues affecting either cost, rate or quality and directing you to the most appropriate development workflow to improve the process
- Optimization - An expansion on the development workflows where a larger number of options are considered to achieve the best mixture of cost, rate & quality for your application.