Thermal gel and putty

All three are dispensable TIMs but differ in rheology and cure. Grease (TIG) is liquid-like, sub-50 µm bondline, and can pump out under cycling. Putty (single-part TIF0xx) is a stiffer, paste-like one-time application that holds its shape after dispense — bondlines run 100 µm to 1 mm. Two-part gel (TIF0xxAB) is mixed then cures into a permanent soft elastomer (Shore 00) — gives gasket-like sealing plus thermal transfer. Pick by: bondline thickness, automated-dispense compatibility, and whether you want a permanent set.

Single-part is faster on the line: apply, place the heatsink, ship. No pot-life clock, no mix-ratio control. Suits high-volume automotive and consumer electronics. Two-part is preferred when (a) the assembly will see vibration that would migrate uncured gel, (b) the joint must seal against fluids or gas after cure, or (c) you need a permanent soft elastomer that won't flow with temperature. Two-part has a measurable working life (typically 30 min – 24 h depending on grade) so dispensers must be timed correctly.

Wave-absorbing thermal gels combine thermally conductive ceramic fillers with EMI-absorbing magnetic powders — same physical layer does dual duty: heat conduction (typically 3–5 W/m·K) plus radio-frequency absorption (peak ~17 dB at 8–14 GHz on TIF030-WA / TIF050-WA). Use cases are 5G mmWave radio modules, automotive radar, and SerDes interconnects where standing-wave reflections degrade signal integrity. Saves a separate ferrite tile.

Single-part putty typically dispenses as a controlled bead (volumetric pump or auger) and squeezes to 100–500 µm under assembly clamp. Two-part cured gel sets at the dispensed thickness (300 µm – 1 mm common) — clamping during cure compresses to target. Lower bondline always means lower thermal resistance, but gel's value is exactly when surface flatness or stack tolerance prevents reliable sub-100 µm application. If you can hit 50 µm flat, use grease; if you can't, use gel.

Single-part putty is removable with isopropanol and a plastic scraper — cleaner reworks than cured silicone. Two-part cured gel forms a soft solid (Shore 00 hardness) that peels off with care, similar to a gap pad. Wave-absorbing gels rework like the parent dispense form. None of these reworks bring the joint back to factory thermal performance — re-application is required, and the cured-gel residue must be fully cleaned before bonding a fresh layer.

Yes — TIF0xx gels are silicone matrix. For silicone-sensitive applications (optical sensors, MEMS, hermetically sealed assemblies that fail under siloxane outgassing), specify a non-silicone alternative — Z-Paster non-silicone pads handle this duty though they don't dispense. We can advise on silicone-free dispensable options on request; not all conductivity grades are available in non-silicone form.