August 9, 2021
The LED aluminum is the PCB, which is also the meaning of the printed circuit board, but the material of the circuit board is aluminum mix/mixture (of metals). In the past, the material of our general circuit board was glass fiber, but because the LED creates heat, the circuit board for LED lamps is generally Aluminum or copper can permit the flow of heat quickly. Circuit boards for other equipment or electrical appliances are still glass fiber boards!
The Aluminum PCB or Copper PCB can minimize the thermal resistance and make the aluminum substrate have excellent thermal conductivity; compared with thick-film ceramic circuits, its mechanical properties are extremely excellent.
In addition, aluminum and copper substrates have the following unique advantages:
Ø Meet RoHs requirements;
Ø More suitable for SMT process;
Ø Extremely effective treatment of thermal diffusion in the circuit design scheme, thereby reducing the module operating temperature, extending the service life, and improving power density and reliability;
Ø Reduce the assembly of radiators and other hardware (including thermal interface materials), reduce product size, reduce hardware and assembly costs; Ø Optimize the combination of power circuits and control circuits
Ø Replace fragile ceramic substrates to obtain better mechanical durability.
What is the composition of aluminum substrate / copper substrate
Ø Line layer
After etching, a printed circuit is formed to realize the assembly and connection of the device. Compared with the traditional FR-4, with the same thickness and the same line width, the Aluminum PCB can carry a higher current
Ø Insulation
The insulation layer is the core technology of the aluminum substrate, which mainly plays the functions of bonding, insulation and heat conduction. The aluminum substrate insulation is the largest thermal barrier in the power module structure. The better the thermal conductivity of the insulation layer, the more favorable it is to spread the heat generated during the operation of the device, and the lower the operating temperature of the device, so as to increase the power load of the module, reduce the volume, extend the life, and increase the power output .
A typical motor controller module uses a large number of heat sinks, thermal interface materials and other accessories. The module is bulky, the structure is complex, and the assembly cost is high. The aluminum substrate on the left side has a Highly automated surface-mount products, the entire product has reduced from 130 to 18 components, the power load has increased by 30%, and the module size has been greatly reduced. This type of high power density module can only be qualified with an aluminum substrate with high thermal conductivity.
Ø Metal substrate
What kind of metal is used for the insulating metal substrate depends on the comprehensive consideration of the thermal expansion coefficient, thermal conductivity, strength, hardness, weight, surface state and cost of the metal substrate.
In general, considering the conditions such as cost and technical performance, aluminum plate is an ideal choice. Available aluminum plates are 6061, 5052, 1060 and so on. If there are higher requirements for thermal conductivity, mechanical properties, electrical properties and other special properties, copper plates, stainless steel plates, iron plates and silicon steel plates can also be used.
Ø Characteristics of aluminum pcb sheet
Aluminum pcb / copper pcb (metal-based heat sink (including aluminum substrate, copper substrate, iron substrate)) is a low-alloyed Al-Mg-Si series high-plasticity alloy plate (see the figure below for structure), which has good thermal conductivity 、 Electrical insulation performance and machining performance. Compared with the traditional FR-4, the aluminum pcb adopts the same thickness and the same line width. The aluminum pcb can carry a higher current. The aluminum substrate can withstand voltages up to 4500V and the thermal conductivity is greater than 2.0, mainly aluminum pcb in the industry, copper substrates have strong heat dissipation, and are mainly used in high-power products
● Using surface mount technology (SMT);
● Extremely effective treatment of thermal diffusion in circuit design schemes;
● Reduce product operating temperature, improve product power density and reliability, and extend product life;
● Reduce product volume, reduce hardware and assembly costs;
● Replaces fragile ceramic substrates for better mechanical durability. structure
Aluminum-based composite copper board is a metal circuit board material, consisting of copper foil, thermally conductive insulation layer and metal substrate. Its structure is divided into three layers:
