The main raw material for soldering tip is copper. And the best thermal conductivity of copper is red (purple) copper. Copper, as a thermal conductor, is the main component of the soldering iron tip, accounting for about 90% of the soldering tip material. The red copper thermal conductivity is good, which helps the soldering iro tip to heat up quickly. However, in order to get more profit some factory use yellow copper which will save cost in the same time, which will reduce the thermal conductivity greatly. And will cause the soldering station do not meet the setting output temperature, and lower the soldering effect and heating recovery. In addition, heat resistance for yellow copper is not as good as red copper. Normally we cannot distinguish the raw material from the soldering bit appearance, but we can choose some reliable supplier.