The earliest and most important driving force for the electronics manufacturing of
lead-free tin bar mainly comes from two EU directives (WEEE and ROHS). These regulations explicitly prohibit the use of heavy metals such as lead, cadmium, mercury and hexavalent chromium in electrical and electronic products. PBB and PBDE are two flame retardant materials.
The present value definition of the ROHS Directive states that each unit of homogeneous material in electrical and electronic products must not exceed a limit value. For parts, the object of restriction is directly the homogeneous material that makes up the part, not the whole part, and the requirements are very strict.
Therefore, Want needs to effectively control hazardous substances from the raw material stage of producing parts. For example a common integrated circuit including the internal leads of the chip and the package. Packages, leads, lead plating, high temperature solder for die bonding, etc. exceeded the standard based on the number of points and the component did not meet the requirements.
If the lead pin contains a thin layer of traditional tin-lead plating, it is not ROHS compliant, and of course it is not a lead-free bar.