The high-quality lead-free solder paste developed by ZhongYa (Tianjin) Company is made up of environment-protection organic flux and high-grade soldering tin powder. The lead-free paste produced by our company is endued with good rheological performance and silkscreen print performance. It is free of mesh block and shows good performance of wettability and spreadability during reflow soldering process. The advanced paste-making equipment and strict quality management system ensure its reliability and stability. So it can be used for assembly and surface paste of various high-density integrated IC board and regurgitant soldering of membrane and thick hybrid circuit.
SMT solder pastes
2-1 No Cleaning Lead-Free Solder Pastes
2-1-1 Product characteristics:
1)Adopt lead-free environment-protection alloy.
2)New Technical support, special chemical ingredient, provide with favorable wettability to make up for poor wettability of lead-free alloy to ensure high reliability.
3)Little residue after reflowing which has no corrosion and good electrical insulation.
4)Adopt high-efficiency thixotropic agent to prevent subseidence as preheating and printing.
5)Meet the American standard of ANSI/J-STD-004 flux (ROLO).
6)The diameter of tin powder is accurately controlled between 25μm to 45μm, and the flux is specifically made to insure continuously printing and fine pattern.
7)Advanced moisture-keeping technology and persistent viscidity ( viscosity above 48 hours), more than 8 hours of valid working life.
8)The residue is clear and has little influence to test.
9)Lucent soldering point and other favorable performance.
2-1-2 Designation,Melting Point and Alloy Compositions
Series |
Melting point (℃) |
Alloy compositions |
WH-326G-M(2-1) |
217-220℃ |
S-Sn96.5Ag3Cu0.5Ce |
WH-373G-M(2-1) |
216-228 |
S-Sn99Cu0.7Ag0.3 |
WH-210G-M(2-1) |
234-240 |
S-Sn95Sb5 |
2-1-3 Flux Chemical Composition
Materials |
Content (wt%) |
Resin |
40 |
Thixotropic agent |
10 |
Acid |
4 |
Solvent |
39 |
Corrosion inhibitor |
3 |
Viscosity additive |
2 |
Active polymer |
2 |
2-1-4 Properties
Item |
Data |
Halogen content (%) |
<0.2 |
SIR(Ω) |
Before soldering |
>1×1012 |
Moist resistance |
>1×1011 |
Flux content (wt%) |
10.0±1.0 |
Flux content(Wt%) |
90±0.5 |
Powder size(μm) |
25~45 |
Viscosity (Kcps/Pa.s) |
500~800 |
Copper mirror corrosion |
pass |
Collapse test |
pass |
Wetting test |
pass |
Shelf life |
6 Months (0-10℃) |