Motorsport Composite Fundamentals: Epoxy
Watch This Course
$199 USD
-OR-
Or
8 easy payments of only $24.88 USD
Instant access. Easy checkout. No fees.
Epoxy
03.13
| 00:00 | Epoxy resins are often seen as the gold standard resins for the construction of high performance composites. |
| 00:06 | And while they do have their advantages, they also come with some things to consider. |
| 00:11 | Just like polyester resins, these can be formulated to achieve specific properties and tailored to specific applications. |
| 00:18 | Let's first cover the key disadvantage of epoxy resin, besides the higher price tag. |
| 00:24 | Compared to the polyester resin that we just discussed, epoxy resins don't have as good UV resistance. |
| 00:31 | Meaning when they're left exposed to the sun, they will begin to break down faster. |
| 00:36 | The most significant effect of this is the resin discoloring and turning from clear to a yellow tinge, while also appearing hazy and becoming more brittle. |
| 00:45 | Clearly, this is a concern for us making car parts, as they'll almost certainly be exposed to UV light. |
| 00:51 | But it's also something that we can minimize if we're aware of it. |
| 00:56 | For example, storing the vehicle inside or at least covering it when that's not possible. |
| 01:01 | After putting all of this hard work into producing a high quality composite part, it's natural that we want to show off the material. |
| 01:08 | So, understandably, we might not want to paint the parts for protection. |
| 01:12 | With that in mind, it is possible to purchase UV stable epoxy resins, designed for use as a finishing coating for visual applications. |
| 01:21 | And this can significantly increase the UV resistance of the parts. |
| 01:26 | Aside from this, epoxy resins offer some significant advantages, making them well suited to high-performance applications like motorsport. |
| 01:34 | During construction, there's much lower shrinkage than with polyester resins, resulting in a higher quality and more dimensionally accurate parts. |
| 01:43 | This also reduces the internal stresses in the part and leads to a much stronger bond between the matrix and the reinforcement. |
| 01:50 | This results in better mechanical properties like strength and stiffness to weight ratios. |
| 01:55 | The curing process is initiated through the addition of a hardener to the resin. |
| 01:59 | And it should be mentioned that fast and slow hardeners are available and can also be blended to achieve the desired cure speed. |
| 02:07 | Generally, speaking, a slower cure will result in a higher quality part. |
| 02:11 | Although the real difference is really in regards to the workable time of the resin and the production time for the parts, which all depends on the individual circumstances of the part and the maker. |
| 02:23 | Before moving on, another advantage of epoxy resin is the heat resistance. |
| 02:27 | It can handle much higher temperatures than polyester resins, which is critical for use in certain areas of a race car, particularly in the engine bay or around the drivetrain. |
| 02:37 | The key points to remember here are that although UV exposure can cause epoxy resin to degrade, this can be avoided with relatively simple precautions in most cases. |
| 02:48 | After mixing the resin and hardener, the slower curing time is partially responsible for lower shrinkage, which provides a better quality final part, both dimensionally and with regards to better mechanical properties. |
| 03:02 | Epoxy resins also boast better heat resistance over polyester, but as you'd expect, this all comes at a higher price tag. |
