Fr 4 Tg

Updated October 6, 2026

Overview

Product sourcing insights & recommendations

23 来源

The term FR-4 Tg refers to the Glass Transition Temperature (Tg) of Flame Retardant 4 (FR-4) printed circuit board (PCB) materials. This threshold marks the point where the resin matrix transitions from a rigid "glassy" state to a "rubbery" state, directly impacting the board's thermal stability and mechanical reliability Eurocircuits Protoexpress.

Market Trends & Forecasts

The global FR-4 PCB market is experiencing steady growth, driven by advanced technological sectors:

* Market Size: Valued at USD 45.02 billion in 2026, with a projected rise to USD 56.14 billion by 2031 (4.51% CAGR) Researchandmarkets.

* Dominance of High Tg: The high-Tg segment (170°C+) is rapidly expanding, fueled by Electric Vehicles (EVs), AI servers, and 5G base stations, which require superior thermal management Researchandmarkets Researchandmarkets.

* Sustainability: Increasing regulatory pressure is shifting the market toward Halogen-Free FR-4 variants to meet environmental standards Researchandmarkets.

* Production Shift: Manufacturing is diversifying from China to regions like India and Vietnam to mitigate geopolitical supply chain risks Researchandmarkets.

Technical Specification Comparison

Feature	Standard FR-4	High-Tg FR-4
Tg Range	130°C – 140°C	170°C – 180°C+
Operating Temp	Moderate	Very High (>340°C decomposition)
Applications	Consumer electronics Linkedin	AI Data Centers, EVs, Aerospace Fortunebusinessinsights
Reliability	Basic	Superior (low thermal expansion) Aivon

Sourcing Insights

* Pricing: Standard boards are highly affordable ($0.20–$0.45/unit for small DIY plates), while professional-grade high-Tg 170 sheets typically range from $1.50 to $2.80 depending on volume Alibaba Alibaba.

* Supply Chain: High-Tg glass yarns are subject to tighter supply, with lead times potentially reaching 16 weeks during peak disruptions Researchandmarkets.

I have compiled detailed lists of standard and high-Tg FR-4 products and suppliers in the files below.

Here are the latest FR-4 Tg insights and product options. You can continue with:

Sources & References

23 sources cited · Verified industry data & reports

High Tg PCBs

Sierra Circuits

Standard FR-4 boards have a Tg of around 130 to 150 °C. High-temperature PCBs offer better mechanical and chemical resistance to heat and moisture compared to ...

What does the Tg value mean

Eurocircuits

The Tg value (temperature) of FR-4 is a crucial selection criterion for engineers and PCB designers. At this temperature, the resin transitions ...

FR4 PCB Material Manufacturing - Fast & Affordable

JLCPCB

Flame Retardant 4, or FR4, is a material grade used in PCB manufacturing. It is made of fibreglass and "4" represents the UL94 V-0 flammability standard (it ...

What Tg means to FR-4 board? - Technology

PCBWay

Conventional FR4 KB-6160 Tg value is 135℃, (5% weight loss ) Td value is 305℃. FR4 lead-free KB-6168LE Tg value is 185℃, (5% weight loss) Td ...

Fr4 Maximum Temperature and Thermal Dissipation

Cadence

Fr4 maximum temperature will determine impedance and other signal integrity standards to take into account for your circuit designs.

High Tg PCB vs. Standard FR4: The Engineering Guide to ...

NextPCB

The Glass Transition Temperature (Tg) is a fundamental property of the amorphous polymer resin matrix in FR-4 substrates. It marks the ...