Plastics Material Selection
Beginning the development of a new plastic product, or redesigning one, can seem daunting given the vast selection of available materials. The first step to developing a product should be to fully understand your application. All possible variables that can impact your product should be identified. These variables greatly impact not only your design parameters but, more importantly, the safety of your product. We will highlight the importance of a few of these variables.
Our team of experienced engineers can walk you through the complete design consideration process.
Temperature
Selecting a plastic material with the appropriate temperature properties is crucial
Temperature will be one of the most significant factors in most applications. A plastic product subject to excessively high temperatures over time will have its mechanical, chemical, electrical, and many other properties critically affected.
Factors of design that relate to temperature:
- Distortion
- Softening
- Expansion
- Conductivity
- Fatigue
- Service Life
Mechanical Properties
The greater the expected stresses, the more important the design.
In applications where plastic components are designed to withstand stress, the mechanical properties of polymers play a particularly important role. It is crucial that a material is designed to withstand the forces that the application will require of it.
The fundamental mechanical material characteristics include
- Strength
- Stiffness
- Hardness
- Toughness
Flammability
The flammability of a material is extremely important for applications where the material will be subject to high temperatures.
Most plastics are carbon-based materials and will burn and give off gases and smoke when subjected to a flame. Plastics are excellent fuels but are generally classed as ordinary combustibles and fall into the same category as wood, leather and many other common materials. All of these materials will degrade at very high temperatures into volatile and gaseous combustion products.
Safety
There are several main areas of safety related to plastic material and design including:
- Fire – Prevent Spread of fire originating within equipment.
- Potential Energy – Injury or fire may result from a short circuit between adjacent poles of high current supplies
- Electrical – Prevent human contact with hazardous voltage
- Mechanical – Enclosures must have adequate mechanical strength to remain safe when subjected to handling as may be expected
To limit failure consequences, compliance agencies have established performance criteria that can be used during material selection and part design. The most universally accepted independent organization to have established provides product safety testing and certifications is Underwriters Laboratories (UL). Their UL94 testing procedures and rating system for thermoplastics flammability are the generally accepted standard throughout most of the world.
The quality that AMFAS upholds at all levels will give you the peace of mind that your safety standards will be met.
Understanding the above factors affecting plastics and using that knowledge to select the appropriate material for your product is made much easier through the use of data sheets for specific materials. However, narrowing down a specific material from the many available materials is no small task. Connect with the team at AMFAS International to have your product specified, designed, manufactured, and delivered.
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