SEMICOSIL 9671 TC4 is a silicone 2K gap filler from Wacker, rated 2.3 W/m·K. Typical uses: Low-density gap filler for automotive/power electronics, battery. Short answer: we dispense it with a PDP two-component progressive cavity metering pump with a static mixer.
Material at a glance
| Manufacturer | Wacker |
|---|---|
| Type | 2K gap filler |
| Chemistry | Silicone |
| Thermal conductivity | 2.3 W/m·K |
| Mix ratio | 1:1 |
| Viscosity | 70,000 mPa·s |
| Cure | 12 h at 23 °C |
From the manufacturer's published data (source). Always work from the current technical data sheet.
How we dispense it
For a two-component gap filler we start with a PDP two-component progressive cavity metering pump and a disposable static mixer, fed from dual cartridges for lab and low volume, or from pails with a follower-plate pail pump for production. Pump size depends on your shot or bead size and cycle time.
- Abrasion: the ceramic filler that carries the heat wears pumps out. We use tungsten carbide rotors and wear-resistant stators and run the pump slowly, at 8 to 12 rpm, for long wear life.
- Ratio: each side is metered by its own progressive cavity pump to within ±1%. Check ratio by weighing a shot from each side every week, because filled materials vary from batch to batch.
- Mixing: a disposable static mixer does the mixing. Purge or change it before the material's working life runs out.
- Dispense pattern: gap fillers are squeezed between the part and the housing, so the pattern (dots, lines or a star) decides coverage and whether air gets trapped.
See our PDP two-component metering pumps, or use the pump configurator.
Frequently asked questions
What pump should I use to dispense SEMICOSIL 9671 TC4?
For a two-component gap filler we start with a PDP two-component progressive cavity metering pump and a disposable static mixer, fed from dual cartridges for lab and low volume, or from pails with a follower-plate pail pump for production. Pump size depends on your shot or bead size and cycle time; send us those and we will size it.
Can SEMICOSIL 9671 TC4 be fed from pails instead of cartridges?
Cartridges suit lab and low volume. Above that, a follower-plate pail pump feeds the metering pump directly, which cuts container changes and waste.
How do you keep SEMICOSIL 9671 TC4 on ratio?
Each side is metered by its own progressive cavity pump, held to within ±1% per side. We recommend a weekly check: weigh a shot from each side and adjust, because filled materials vary from batch to batch.
Will SEMICOSIL 9671 TC4 wear out the pump?
Thermally conductive fillers are abrasive. With tungsten carbide rotors, wear-resistant stators and pump speeds of 8 to 12 rpm, stators typically last 6 to 12 months and rotors up to 24 months, and a pump rebuild takes under an hour.
Talk it through with us
Running SEMICOSIL 9671 TC4, or about to? Send us the technical data sheet, your bead or shot size and your cycle time, and we'll recommend a pump and feed system. We can run an application test on your material before you buy. Contact us
Related materials
- SEMICOSIL 961 TC A/B · Wacker, 2K gap filler
- SEMICOSIL 9649 TC · Wacker, 2K gap filler
- SEMICOSIL 9673 TC A/B · Wacker, 2K gap filler
- BERGQUIST GAP FILLER TGF 4000 · Henkel Bergquist, 2K gap filler
- BERGQUIST GAP FILLER TGF 3600 · Henkel Bergquist, 2K gap filler
- BERGQUIST GAP FILLER TGF 4400LVO · Henkel Bergquist, 2K gap filler (low volatility)
All thermal interface materials · Materials we've dispensed
SEMICOSIL 9671 TC4 is a trademark of Wacker or its affiliates. Dispense Robotics is not affiliated with the manufacturer; the name is used to describe the material our equipment dispenses.