Study The Laed-Free Solder Selection Method And Process Optimization

In recently these decades, electric industry not only has brought convenience and benefit for the mankind but also brought a lot of electronic rubbish to the society too. The negative influence that the electrical and electronic rubbish caused is a baptism of fire to global ecological environment .In order to control the electronic pollution of the ecological environment of rubbish, EU Committee issued"Restriction of Hazardous Substances"(abbreviated as R O H S order) in 2003, and begin implementation on July 1, 2006.ROHS stipulate clearly that electric industry has to restrict the use of Pb, this make electric industry that has used Sn-Pb solider for a long time faces a huge challenge. So how to familiar with the properties of the lead-free solder, choose the suitable solder for process in short time and improve the process ability is primary problem for the electronic part production now.In the paper, through researching the characteristic of the lead-free solder, we introduce the method of QFD (quality function deployment) to transform the demand of production properties and process into the technical demand of the lead-free solder, thus we could transform the demand concept of sampling into a concrete performance index. Finally we can obtain two parameters of the technological competitive power index and market competitive power index to evaluate performance of the lead-free solder through making a series of experiments. We utilize the design of experiment method to find out key parameter of process and the best collocation of parameter, which make the coplanarity of socket tin ball desend to 149 from 178 and promote the process's ability up to 95.2% from 85%.