LAIRD TPUTTY 502FG2
Harmonization Code : 8473.30.80.00 | Parts and accessories (other than covers, carrying cases and the like) suitable for use solely or principally with machines of headings 8470 to 8472 ; Parts and accessories of the machines of heading 8471 ; Other; Other
Main features
- 3.0 W/(m K) Thermal Interface
- Ultra-Soft 14 Shore 00 Material
- Thermal Interface Material
Product Description
Tputty™ 502FG2 Silicone Based Thermal Gap Filler is a white, fiberglass-reinforced, boron-nitride-filled silicone interface material for applications with large tolerance variation and compression beyond 50% of the original thickness. The naturally tacky sheet requires no separate pressure-sensitive adhesive coating and is designed to conform under relatively low component pressure. Typical published properties include 3.0 W/m·K thermal conductivity, 14 Shore 00 hardness, 0.49 °C·in²/W thermal resistance at 40 mil and 10 psi, 0.11% TML, 0.06% CVCM, and a -45°C to 200°C operating range.
Key features
- Fiberglass-reinforced putty-like silicone gap-filler sheet
- Typical 3.0 W/m·K thermal conductivity
- Very soft 14 Shore 00 hardness for high compression and low component stress
- Naturally tacky on both sides without a separate adhesive coating
- Available from 0.50 to 5.0 mm in 0.25 mm increments
- ASTM E595 outgassing values of 0.11% TML and 0.06% CVCM
- UL 94 V-0 positioning, subject to the recognised formulation and test construction
Applications
- Automotive ADAS, infotainment, electronics, and powertrain or ECU assemblies
- Wireless infrastructure, routers, and telecom/datacom equipment
- Gaming systems, notebooks, tablets, and portable devices
- Aerospace, defence, instrumentation, drones, and satellite-related assemblies
TDS, SDS & Technical Documents
Technical Specifications
General Properties
Thermal Properties
Electrical Properties
Additional Information
Tputty™ 502FG2 Silicone Based Thermal Gap Filler
A white, boron-nitride-filled silicone sheet reinforced with fiberglass on both sides. It is designed for interfaces with substantial tolerance variation where the material may need to compress beyond 50% of its original thickness while limiting pressure on the cooled components.
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Reinforced sheets, die-cut parts, and bulk material
| Configuration | Published availability | Selection context |
|---|---|---|
| Sheet thickness | 0.50 to 5.0 mm (0.020 to 0.200 in) | Available in 0.25 mm (0.010 in) increments; ±10% thickness tolerance. |
| Standard sheet size | 229 × 229 mm and 457 × 457 mm | 9 × 9 in and 18 × 18 in; current page states 9 × 9 only above 0.100 in. |
| Reinforcement | Fiberglass on both sides | FG2 designation; supports handling of the soft material. |
| Die-cut parts | Custom shapes available | Final geometry, tolerances, liner, packaging, and orientation require quotation confirmation. |
| Bulk form | 100 cc, 500 cc, and 1000 cc jars | Bulk material is a distinct supply form and should not be assumed equivalent to an FG2 reinforced sheet in handling. |
Select nominal thickness from the assembled gap and required compression
- Measure the complete tolerance stack between the heat source and mating heat sink, housing, chassis, or spreader.
- Select nominal sheet thickness to maintain contact across minimum and maximum gaps without exceeding component load limits.
- The product is positioned for compression beyond 50% of original thickness, but the actual design must use pressure-versus-deflection data for the selected thickness.
- Keep surfaces clean and dry and avoid contamination that reduces wet-out or tack.
- Use the natural tack for temporary placement; do not add a separate adhesive layer unless specifically qualified.
- Control pad position, compression stops, fastener load, edge squeeze, and potential lateral flow in the finished assembly.
- Requalify thermal resistance and mechanical stress after rework or reassembly.
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Storage and industrial handling
The current product page states a two-year shelf life from date of shipment. Store the material in its original packaging and protect the soft, tacky surfaces from dust, damage, distortion, and incompatible chemicals. The current US SDS was updated in March 2025; final publication and use require confirmation of the exact regional SDS and package label for the selected part number.
Soft compression behaviour and thickness-dependent interface resistance
Thermal conductivity is a bulk property. Thermal resistance and component stress depend on product thickness, final compressed thickness, pressure, surface flatness, interface count, contact area, and assembly design.
| Property | Typical value | Test context |
|---|---|---|
| Construction | Fiberglass-reinforced boron-nitride-filled silicone sheet | FG2 has reinforcement on both sides. |
| Thermal conductivity | 3.0 W/m·K | ASTM D5470. |
| Thermal resistance at 40 mil and 10 psi | 0.49 °C·in²/W | Modified ASTM D5470; thickness- and pressure-specific. |
| Hardness | 14 Shore 00 | ASTM D2240. |
| Deflection at 10 psi | 11% | Current 20 mil part-page value. |
| Deflection at 50 psi | 30% | Current 20 mil part-page value. |
| Deflection at 100 psi | 55% | Current 20 mil part-page value; thickness and test construction matter. |
| Density | 1.37 g/cm³ in 2017 datasheet; 1.30 g/cm³ on current product pages | Confirm controlled current value. |
| Operating-temperature range | -45°C to 200°C | Laird test method; not a universal service-life guarantee. |
| Outgassing TML / CVCM | 0.11% / 0.06% | ASTM E595. |
| Dielectric constant | 3.6 | 2017 datasheet states 10 GHz; current product page does not display frequency. |
| Volume resistivity | 5 × 1013 ohm-cm | ASTM D257. |
| Flammability | UL 94 V-0 | Formulation-, thickness-, and construction-specific classification. |
Product-specific testing across three thicknesses and environmental conditions
The Tputty 502 Thermal Reliability Report tested 20 mil, 40 mil, and 200 mil specimens in aluminium heater and cooler fixtures. Two fixtures per thickness, with three test positions per fixture, were evaluated. The measured endpoint was average temperature difference at constant heat flow, used as an indicator of thermal-resistance change.
-40°C to 200°C, one-hour holds at each extreme, transfer under 20 seconds, and 1000 cycles.
200°C exposure for 1000 hours in the documented fixture.
85°C and 85% RH through 1000 hours; the supplier report labels this condition HAST.
The report states that endpoint thermal resistance was slightly lower than the initial value and attributes this to bondline thinning and progressive surface wet-out. The evidence supports stability only for conditions and fixture configurations similar to those tested; it does not establish universal service life.
Use high compressibility to accommodate variable gaps without assuming negligible stress
Published applications include automotive ADAS, infotainment, powertrain and ECUs; routers and wireless infrastructure; gaming systems and portable devices; instrumentation; drones and satellites; and other aerospace, consumer, industrial, and telecom/datacom assemblies. Final qualification should establish nominal thickness, complete tolerance stack, compression pressure, final thickness, thermal resistance, lateral flow, tack, rework, vibration, cycling, outgassing, and electrical clearances.
Tputty 502 Thermal Reliability Report
The product-specific report documents the fixture, test population, three tested thicknesses, thermal-shock profile, 200°C bake, 85°C/85% RH exposure, recorded temperature differences, and supplier conclusion.
Validate Tputty™ 502FG2 for your compressed thermal interface
Krayden can help review tolerance stack, sheet thickness, die-cut geometry, compression pressure, final thickness, component stress, thermal resistance, pad retention, rework, vibration, outgassing, environmental cycling, and assembly qualification.
