Selection FAQ

Q1. What does Dr.H New Material do, and what are its main products?

Dr.H New Material (Fuzhou Dr.H New Material Co.,Ltd) focuses on two product families: silicone thermal pads and conductive foam for EMI shielding. Thermal conductive pads fill the gap between a heat source and a heat sink to reduce interfacial thermal resistance. Conductive foam uses a foam core wrapped with a conductive layer for EMI shielding and grounding across structural gaps, and can be die-cut into strips, frames or custom-shaped parts. The company was founded in August 2020 and is based in Minhou County, Fuzhou, Fujian.

Q2. Where are Dr.H New Material's thermal pads and conductive foam typically used?

Dr.H New Material's thermal conductive pads and conductive foam mainly serve six application areas: AI computing servers, new energy and energy storage (PCS and battery packs), telecom base stations, industrial power supplies, high-end industrial control, and consumer electronics. Thermal pads are used for interface filling between chips, power modules and heat sinks. Conductive foam is used for grounding and shielding at chassis seams, access doors and shielded cavities. Each industry weighs thermal conductivity, flame retardant grade and shielding effectiveness differently, so provide the operating temperature and gap dimensions first.

Q3. What qualifications does Dr.H New Material hold, and can you test and run thermal simulation in-house?

Dr.H New Material covers the full process chain for thermal conductive pads and conductive foam in-house, from silicone compounding, calendering and slicing through to die-cutting, including downstream adhesive backing and lamination. The company is a high-tech enterprise (certificate No. GR202335000499) with 15 published patents and a Grade A tax credit rating. An in-house materials laboratory supports thermal simulation assessment, providing heat-path analysis as a reference before mass production. The scope of assessment is subject to commercial confirmation.

Q4. What thermal conductivity should I choose for a thermal pad, and is a higher value always better?

No. Select thermal conductivity from power dissipation and the thermal resistance budget rather than pushing the value as high as possible. Dr.H New Material thermal conductive pads cover 1.0-15.0 W/(m*K): 1.5-3.0 is usually sufficient for low-power consumer devices, 3.0-6.0 is recommended for AI computing servers and power modules, and above 6.0 can be considered for high heat flux with a well-controlled gap. Thermal conductivity is a material property only; actual thermal performance also depends on thickness, compression and assembly pressure. All parameters are subject to the actual test report.

Q5. How do I choose thermal pad thickness, and does a thicker pad dissipate heat better?

No. Choose the thinnest value that still fills the gap. Dr.H New Material thermal conductive pads are available from 0.3 to 40.0 mm. A practical method is to take the measured gap and add a 10%-20% compression allowance: for a 1.0 mm gap at 20% compression, choose 1.2-1.3 mm. Increasing thickness raises interfacial thermal resistance, so do not compensate for loose structural tolerances with a thicker pad. Consider thickness above 5 mm only for large gaps or clear coplanarity deviation. All parameters are subject to the actual test report.

Q6. How do I choose thermal pad hardness in Shore 00, and is softer or harder better?

Hardness sets the balance between conformability and resistance to sag: a softer pad conforms better, while a harder one withstands assembly better. Dr.H New Material thermal conductive pads cover Shore C 10-50 (ASTM D2240) and can be supplied to a specified hardness within that range. For rough surfaces or heat sinks with coplanarity deviation, the softer end (around Shore C 10-20) conforms better; for large flat areas or vertical mounting where shift and sag resistance matter, the harder end (around Shore C 40-50) is preferred. Lower hardness increases the tendency toward cold flow and oil bleed, so power supply and energy storage projects sensitive to long-term reliability should stay in the middle of the range. All parameters are subject to the actual test report.

Q7. What does thermal pad compression rate mean, and how much compression should screw fastening apply?

Compression rate is the percentage of thickness the pad loses under load; 10%-30% is a stable engineering range. Dr.H New Material thermal conductive pads cover a compression range of 10%-50%. Insufficient compression leaves air at the interface, while excessive compression raises internal stress and accelerates the loss of resilience. Assembly force should be calculated from hardness and contact area: higher hardness and larger contact area require higher fastening force. Screw layout should keep pressure distribution even. All parameters are subject to the actual test report.

Q8. Does a thermal pad need to be flame retardant, and how do I choose the UL94 grade?

In most cases flame retardant grades are a standard purchasing requirement. Dr.H New Material supplies thermal conductive pads in flame retardant grades: consumer electronics and industrial control usually require UL94 V-0, while PCS and battery packs in new energy and energy storage call for V-0 as a priority because of the higher safety margin, with attention to flame retardant stability after long-term thermal aging. For sealed cabinets, smoke density and toxicity requirements should also be confirmed. Lock the flame retardant grade together with thickness, colour and thermal conductivity before sampling. All parameters are subject to the actual test report.

Q9. Is a thermal pad electrically insulating? Will it conduct or break down?

Thermal conductive pads are electrically insulating thermal interface materials, but the volume resistivity and withstand voltage margin must be checked on the high-voltage side. Dr.H New Material thermal conductive pads have a volume resistivity of 10^14 ohm-cm (ASTM D257), subject to the actual test report and provide electrical isolation between the heat source and the heat sink. The insulation margin drops if the pad is over-compressed and becomes too thin, if metal debris enters the interface, or after prolonged high-temperature aging. For high-voltage applications such as power modules and PCS, keep a margin and run withstand voltage verification at equipment level. All parameters are subject to the actual test report.

Q10. Should I choose a thermal pad, thermal grease or thermal gel?

The choice depends on gap tolerance and production method; these materials are not drop-in replacements for one another. Dr.H New Material thermal conductive pads suit gaps above 0.3 mm where the gap is well defined and cushioning plus electrical insulation are needed: they can be pre-applied, are easy to rework, and do not sag. Thermal grease offers low thermal resistance but has uncontrolled bond line thickness and tends to migrate, so it fits small, precision interfaces. Thermal gel suits automated dispensing and high-volume lines with large tolerances. This technical direction is under discussion; specific specifications and availability are subject to commercial confirmation.

Q11. How much difference is there between 60 dB and 90 dB shielding effectiveness in conductive foam?

The dB scale is logarithmic: 60 dB means roughly 1,000 times attenuation and 90 dB roughly 30,000 times, so a 20 dB difference is about one order of magnitude. Dr.H New Material conductive foam typically provides 60-80 dB shielding effectiveness over 10 MHz-3 GHz, subject to the actual test report. Selection should consider the target frequency band and seam length: wider bands and longer seams require higher shielding effectiveness. Final performance at equipment level also depends on compression, contact surface conductivity and the grounding path, and should be verified by full-unit testing. All parameters are subject to the actual test report.

Q12. How do I set the compression of conductive foam, and how much gives a stable contact?

Set compression from the gap tolerance and the expected resilience life together; 30%-50% is typical. Dr.H New Material conductive foam covers a compression range of 20%-70%. Too little compression gives unstable contact resistance, while too much accelerates resilience loss and raises the required closure force. For gap tolerances below 0.3 mm, around 30% works in most cases; where tolerances are larger or accumulated deviation must be compensated, use 50% or more. Confirm the closure force the cover can deliver. All parameters are subject to the actual test report.

Q13. What surface resistance is required for conductive foam, and is 0.1 ohm/sq sufficient?

Lower surface resistance means better grounding continuity, and 0.1 ohm/sq or less is sufficient for most shielding applications. Dr.H New Material conductive foam has a surface resistance of 0.05 ohm/sq or less, measured on 25.4 mm x 100 mm, subject to the actual test report and is used for grounding continuity at chassis seams, doors and shielded cavities. For applications with higher requirements on static discharge or low-frequency magnetic shielding, evaluate contact resistance and the full grounding loop rather than the sheet resistance of the covering layer alone. In salt spray and damp heat environments, also watch for resistance drift caused by oxidation. All parameters are subject to the actual test report.

Q14. How do I choose the core material and covering layer of conductive foam?

The core sets the elasticity and the covering layer sets the conductivity, and the two can be combined. Dr.H New Material conductive foam supports combined selection: polyurethane foam gives soft resilience and suits low closure force, while silicone foam offers better temperature and weather resistance for outdoor cabinets. Common covering layers are conductive fabric, metal foil and conductive coating: conductive fabric has lower cost and good conformability, while metal foil delivers higher shielding effectiveness but weaker bend tolerance. For outdoor telecom base stations, prioritize weather resistance; for indoor equipment, prioritize compression recovery and cost.

Q15. What is the difference between conductive foam, conductive adhesive and conductive fabric?

The key question is whether the gap has tolerance that must be compensated. Dr.H New Material conductive foam uses a foam core with a conductive covering layer and recovers after compression, so it shields and grounds while filling uneven gaps. Conductive adhesive mainly bonds, has limited gap-filling capability, and suits thin-layer fixing. Conductive fabric conforms well but offers almost no thickness compensation, so it suits cable wrapping or flat lap joints. For structural seams that need continuous contact pressure, conductive foam is the preferred choice. All parameters are subject to the actual test report.

Q16. Can conductive foam be die-cut into custom shapes, and does it need adhesive backing?

Yes. Die-cutting is a standard downstream process for Dr.H New Material conductive foam, which can be cut to drawing into strips, frames or custom-shaped parts, with adhesive backing and lamination available for automated assembly. Whether to add adhesive backing depends on the assembly method: manual assembly or narrow strips that need pre-positioning generally use adhesive backing, while press-fit structures or covers that require periodic inspection can go without it. Adhesive backing affects the grounding loop, so the conductive approach should be confirmed together with the shielding path. The specific process is subject to commercial confirmation.

Q17. How do I request samples from Dr.H New Material, and are they free?

Provide the operating conditions before the part number; this makes sampling far more efficient. When requesting thermal conductive pad or conductive foam samples from Dr.H New Material, please provide the application industry, interface gap, operating temperature, target thermal conductivity or shielding effectiveness, dimensions and estimated volume, so we can match an existing specification or arrange sampling. Sample specification, quantity, whether a fee applies and the shipping schedule are subject to commercial confirmation. Technical parameters are subject to the actual test report, and we do not recommend judging mass-production feasibility from sample appearance alone.

Q18. What is the minimum order quantity, and do you accept small trial runs?

There is no single threshold: the MOQ varies with specification, die-cutting process and adhesive backing method. Dr.H New Material supports small-batch sampling and trial production for both thermal conductive pads and conductive foam. At the mass-production stage, MOQ is calculated separately for sheets, rolls or die-cut parts; die-cut parts usually carry a higher MOQ than sheets because of tooling and waste stripping. Specific MOQ, tiered pricing and whether a tooling fee applies are subject to commercial confirmation.

Q19. What is the typical lead time, and can urgent orders be expedited?

Lead time depends on whether the specification is standard and whether die-cutting and adhesive backing are required. Standard specifications of Dr.H New Material thermal conductive pads and conductive foam can generally be produced from stocked raw material, while custom die-cut shapes add time for tooling and first-article approval. Specialized grades such as flame retardant or electrical insulation take longer if third-party testing is required. Whether expediting is available, the expediting fee and split delivery arrangements are subject to commercial confirmation.

Q20. Can you customize to our operating conditions, and how does thermal simulation support work?

Yes. Customization to your operating conditions is supported, and simulation assessment can be done before mass production. Dr.H New Material thermal conductive pads and conductive foam can be customized for thermal conductivity, thickness, hardness, colour, flame retardant grade, core and covering layer combination, die-cut shape and adhesive backing method. The in-house materials laboratory can run thermal simulation assessment to help confirm the heat path, material thickness and layout. Customization feasibility, assessment lead time, sampling cost and ownership of intellectual property are subject to commercial confirmation.