[Chinese aluminum industry network] aluminum substrate, English abbreviated ALPCB, is the abbreviation of aluminum base copper clad circuit board, belongs to metal base circuit board (also known as: MCPCB), compared with common FR4 glass fiber board, with good thermal conductivity With high cost performance, after 2007, it quickly became the preferred PCB for LED lighting fixtures, integrating production experience and lighting application information in recent years, and throwing aluminum substrate related topics here. A: metal substrate common structure of metal substrates, such as schematic a, the common structure is 1: conductive layer (also known as copper foil layer), used for line arrangement and component pad position; 2: insulation heat dissipation layer (commonly ceramic Powder PP glue), as the name implies, plays a role in insulation and heat dissipation 3: Metal base layer (usually aluminum base, copper base), as a carrier of copper foil and insulation layer, aluminum base with high cost performance and good mechanical processing performance in the market share of the metal substrate Far ahead. B: General Performance of Aluminum Substrates As more commonly used PCBs for LED lighting fixtures, we are interested in learning more about aluminum substrates. The aluminum substrate is made of aluminum alloy. Its thermal, electrical, and mechanical properties are particularly important. Common parameters include specific heat capacity, thermal conductivity, melting point range, linear expansion coefficient, electrical conductivity, electrical resistivity, hardness, fatigue strength, and tensile strength. , elastic modulus, elongation, cutting force and so on. In the case of conforming to the national standard, the thermal conductivity is particularly important. The concept and measurement method may refer to schematic b, which is more intuitive. Currently, aluminum-based copper clad laminates produced by different manufacturers have large differences in thermal conductivity. If the above measurement methods are used, the thermal conductivity coefficient of aluminum-based laminates in the domestic market is mostly 0.2-1.5 W/MK. The difference in cost is likely to induce the thermal conductivity to be incorrect. Etc., so when considering the thermal conductivity, may wish to refer to the aluminum substrate price positioning and third-party testing. In daily production, the aluminum substrate orders should indicate the following elements as much as possible: First, the product model / item number / order number: The information is clear, self-seeking, and the company's internal and external departments are easy to match! Second, plate types: single-sided / double-sided aluminum-based copper clad laminates, plate thickness and thickness of copper foil (OZ): H, 1,2 (ie 18/35/70mil), less than 18mil plate is also more; Third, the process, including surface treatment, solder resist color, text color and molding methods; is a single form or imposition shipment (the conventional process is generally 5MM, do not forget to stagger plus MARK points and patch technology hole); In addition, such as the delivery period, quantity and special requirements, most of the parties sign a good contract when the order is placed, so that the suppliers can cooperate with each other more powerfully and constrain each other. The order structure of the PCB manufacturers at different times may be different, and these items are different. It is normal that you should carefully screen your cooperation.
