What Is Thermal Paste / Pad?
Thermal paste / pad is an interface material (TIM) that fills the microscopic air gaps between a hot component and a heat sink and improves heat transfer.
Why Is It Needed?
No matter how flat two solid surfaces look, small air gaps remain between them. Since air conducts heat very poorly, these gaps are a barrier. Thermal paste fills them so heat passes efficiently to the heat sink.
Paste and Pad
Thermal paste is a viscous paste; applied thin and even, it gives the best performance. A thermal pad is a pre-cut soft sheet; it's easy to apply and practical when the gap is larger or for several components.
| Type | Feature |
|---|---|
| Paste | Thin layer, best contact |
| Pad | Easy, fills a large gap |
| Conductivity | Measured in W/m·K |
Correct Application
Paste should be applied thin and even; too much paste actually worsens heat transfer. The goal is to fill the gaps, not to build a thick layer.
Where Is It Used?
Processor–heat sink mounting, power transistors, regulators, LED modules and every power component that contacts a heat sink.
Conductive Compounds
Some high-performance pastes contain metal and can be electrically conductive; if this kind of paste overflows, it can short adjacent leads. That's why an electrically insulating paste/pad is preferred in most applications.
Common Mistakes
- Too much paste: a thick layer harms heat transfer.
- Conductive overflow: metal-bearing paste can short leads.
- Drying out: paste that dries over the years must be renewed.
Frequently Asked Questions
Can I go without paste?+
Paste or pad?+
Search parts related to "What Is Thermal Paste / Pad?"
Find the right part by comparing price, stock and distributors.