It should face the following questions if the manufacture of electron product be put in practice lead-free

• Lead-free solder material
• Lead-free component and PCB board
• Lead-free sealing equipment

A.Lead-free solder material

To present,there are hundreds of lead-free solder material reported in the world,but it realy be recognized and at large adopted by way is Sn-Ag-Cu alloy and adopt other alloy,add with In,Bi,Zn etc.Many lead-free alloy solder material coexistence nowaday that lead to the increase of cost and appearing different customer need different solder material and different technics.The development trend will incline to the nuiform alloy solder material.

⑴The melting point is 30 degree higher than Sn-Pb;

⑵The tractility has decline but no long time badding;

⑶The sealing time is commonly 4 sections;

⑷The early days’ and anaphase’s pulling intension are excellent than Sn-Pb;

⑸Strong re-prostration character;

⑹The inquirement of hot stability to the flux is much high;

⑺More content of Sn,it will be quite strong melting to Fe at high temperature because the character of lead-free solder material has decided the new lead-free sealing technics and equipment.

B.Lead-free component and PCB board

In the craftwork flow of lead-free sealing the lead-free technology of component and PCB board plating layer are relatively complex and rather involving fields,which is one of reasons that international enviroment protect ogranize delay the lead-free manufacture proceeding.In quite time,lead-free solder material is coexist with Sn-Pb PCB plating layer which bring the sealing limitation of “lift-off”,the equipment manufacturers have to overcome this phenomena from equipment.Otherwise the requiment of manufacture technics to PCB board has relativity increased and the material of PCB boare and component are required better re-hot quality.

C.Lead-free sealing equipment