Metal Core PCB means the core (base) material for PCB is the metal, not the normal FR4/CEM1-3, etc. and currently the most common metal used for MCPCB manufacturer are Aluminum, Copper and steel alloy. Aluminum has good heat transferring and dissipation ability, but yet relatively cheaper; copper has even better performance but relatively more expensive, and steel can be divided into normal steel and stainless steel. It more rigid than both aluminum and copper, but thermal conductivity is lower than them too. People will choose their own base/core material according to their different application. Generally speaking, aluminum is the most economic option considering thermal conductivity, rigidness, and cost. Therefore, the base/core material of normal Metal Core PCB are made of aluminum. In our company, if not special request, or notes, the metal core refer will be aluminum, then MCPCB will means Aluminum Core PCB. If you need Copper Core PCB, Steel Core PCB, or Stainless steel core PCB, you should add special notes in drawing. Found Circuit, one professional Printed Circuit Board Manufacturer in China, can supply PCB with high quality and pretty competitive price to you. And we have passed ISO9001,ISO14001,TS16949, SGS and UL certificates,hope to have a cooperation with you. Sometimes people will use abbreviation “MCPCB”, instead of the full name as Metal Core PCB, or Metal Core Printed Circuit Board. And also used different word refers the core/base, so you will also see different name of Metal Core PCB, such as Metal PCB, Metal Base PCB, Metal Backed PCB, Metal Clad PCB and Metal Core Board and so on. MCPCBs are used instead of traditional FR4 or CEM3 PCBs because of the ability to efficiently dissipate heat away from the components. This is achieved by using a Thermally Conductive Dielectric Layer. The main difference between a FR4 board and MCPCB is the thermal conductivity dielectric material in the MCPCB. This acts as a thermal bridge between the IC components and metal backing plate. Heat is conducted from the package through the metal core to an additional heat sink. On the FR4 board the heat remains stagnant if not transferred by a topical heatsink. According to Avago’s white paper (AV01-0615EN.pdf) a MCPCB with a 1W LED remained near an ambient of 25C, while the same 1W LED on a FR4 board reached 12C over ambient. LED PCB always be produced with Aluminum core, but sometimes steel core PCB also be used.