High TG PCB
High Tg materials are those whose glass transition temperature (Tg) is greater than 170 °C. Materials with high Tg have the following characteristics: high value for the glass flow temperature (Tg) and high-temperature resistance. A huge need for boards having high Tg has emerged with the advancement of electrical technology. The transition temperature (Tg), which occurs when the core material (polymer and glass) transitions from a solid, hard, and glassy state to a rubbery state, is one of the most crucial characteristics of any epoxy.
The Tg value of each PCB varies depending on the substrate. If the operational temperature of the PCB surpasses its Tg value, the PCB will also begin to alter its state, which will have a negative impact on PCB construction. Because the substrate offers the board higher heat resistance, and mechanical, and chemical stability at high temperatures, high Tg PCB boards are more stable there. The glass transition temperature, or Tg, is a mechanical characteristic that denotes the greatest temp. at which the substrate retains its rigidity. In other words, at high temperatures, the typical PCB substrate not only softens, deforms, melts, and exhibits other phenomena, but also exhibits a dramatic drop in its electrical and mechanical properties, which will have an impact on the lifespan of the product.
Properties
High Tg materials have the following properties:
- High glass flow, temperature value (Tg)
- High-temperature durability
- Long de-lamination durability
- Good mechanical properties
- Low Z axis expansion
- Excellent PTH reliability
- High thermal stress resistance value
Materials with a TG level of 140°C, which can resist an operating temperature of 110°C, are used to make standard PCBs. While this would not be appropriate for operations involving extremely high temperatures that are frequently used in industries like automotive, industrial, or high-temperature electronics. A PCB composed of FR-4 material is frequently the best option in these circumstances.