PTM 7950 | Phase Change Pad

PTM7950 Thermal Impedance (TI) vs. Pressure

Thermal Impedance of PTM7950 is reduced with pressure

Thermal impedance is a measure of the resistance to heat flow across an interface. The higher the thermal impedance, the greater the resistance to heat flow and the lower the rate of heat transfer. This can lead to an increase in temperature at the interface, which can reduce the performance and lifespan of the components.

To increase heat transfer between two surfaces, you want to reduce the thermal impedance at the interface between those surfaces.

What is a Cutbar?

A "cutbar" is a metal bar made of copper or aluminum used to measure thermal performance, simulating heat generated by electronic components. It tests the thermal conductivity of thermal interface material by placing it between the cutbar and a cooling solution, and its performance is observed by measuring its ability to conduct heat away from the cutbar.

The 125W value is the heat dissipated during testing, used to determine thermal impedance.

Bondline thickness of PTM7950 is reduced with pressure

One key characteristic of the PTM7950 is its bondline thickness, which refers to the thickness of the layer of adhesive between two surfaces being bonded. In the image to the left, we can observe how the bondline thickness of the PTM7950 changes under varying pressure conditions.

As the pressure applied to the PTM7950 increases, the bondline thickness decreases. Specifically, a minimum pressure of 10 psi is needed to observe a significant reduction in bondline thickness. This means that lower pressure is sufficient to achieve a thinner bondline, which can be advantageous in certain applications. However, as pressure increases beyond 40 psi, the amount of thin bondline thickness that can be obtained becomes very small. This suggests that higher pressure levels may not result in significantly thinner bondlines and could even be detrimental to the bonding process.

Understanding the relationship between pressure and bondline thickness can be crucial in optimizing the use of the PTM7950 adhesive in different applications. By selecting the appropriate pressure level, it may be possible to achieve the desired bondline thickness, thereby ensuring a strong and reliable bond between surfaces. Furthermore, the pressure level could be adjusted based on the specific application and the materials being bonded, which could further improve the quality and durability of the bond.

PTM7950 Bond Line Thickness, BLT (mm) vs. Pressure (psi)

Thermal Impedance Comparison of PTM7000-series against competitors

PTM7950 is best-in-class against the competition

The thermal impedance values for various materials are shown in the chart on the left, including the PTM 7900 and PTM 7950. Interestingly, both of these materials have the lowest thermal impedance values when compared to all other materials tested, including competitive thermal greases. Overall, the PTM 7950 is the top performer among all materials tested for thermal impedance.

The PTM 7950 is clearly the best choice for thermal impedance, with the lowest value among all materials tested. This makes it an excellent option for electronic devices that require exceptional thermal management.