Assembly Considerations
| Thermal Expansion |
Plastic parts are often attached to components made of materials with much different coefficients of linear thermal expansion (CLTE). If your part will contain different materials, design for CLTE differences. For instance, a higher CLTE plastic part tightly attached to a lower CLTE metal component can bow between attachment points when exposed to elevated temperatures (see figure). Designing the plastic section with slotted holes provides a sliding fit to accommodate dissimilar levels of expansion. You may need to make similar design adjustments when joining plastic parts to parts made of certain polyamides and other plastics that swell significantly as they absorb moisture.
