Introduction to Type 3 T3 Solder Paste and Type T4 Solder Paste

In SMT and SMD soldering processes, solder paste is a key material, and its quality and performance directly affect the quality and reliability of soldering. Solder paste is mainly made of metal powder, flux and additives by stirring and mixing. Generally, lead-free solder paste is composed of tin, silver and copper, such as SAC305 (Sn96.5Ag3Cu0.5), SAC0307 (Sn99Ag0.3Cu0.7) or SAC07 (Sn99.3Cu0.7); while lead-containing solder paste is composed of tin, lead and some alloys are made by adding silver, such as Sn63Pb37 (63 37), Sn60Pb40 (60/40) or Sn62Pb36Ag2 and Sn62.8Pb36.8Ag0.4, etc. The size of the tin powder in the solder paste, such as the size difference between Type 3 powder and Type 4 powder, is one of the important factors affecting the soldering effect. The solder pastes of the above alloys can be made into T3 solder paste or T4 solder paste. This article will introduce why solder paste requires different powder sizes and analyze the impact of different powder sizes on the soldering process.

Why are solder pastes of different powder sizes needed?

The size of tin powder in solder paste is not determined arbitrarily, but is selected based on specific soldering requirements and process parameters. Different sizes of tin powder will produce different effects during the soldering process, so it is necessary to choose whether to use type 3 solder paste or type 4 solder paste according to the specific situation.

Effect of different powder sizes on soldering

Wettability and fluidity: Finer tin powder size like T4, usually has better wettability and fluidity, which can better cover the soldering surface, form uniform solder joints, and improve the soldering quality.

Soldering temperature and speed: Finer tin powder sizes will melt more easily at the same temperature, so the soldering temperature and speed may need to be adjusted accordingly.

Weld Strength and Reliability: Powder size selection also affects the strength and reliability of the weld joint. Finer tin powder sizes generally form more uniform, denser solder joints, improving soldering reliability.

Scope of application and application scenarios: Solder pastes of different powder sizes are suitable for different soldering needs and application scenarios. For example, for soldering of micro-sized components, it may be necessary to use finer tin powder sizes.

The difference between Type 3 solder paste and Type 4 solder paste

The size difference between Type 3 powder and Type 4 powder is mainly optimized for different soldering requirements and process parameters. Type 3 solder paste is also called T3 solder paste, and the size of the tin powder in it is 25-45μm; Type 4 solder paste is also called T4 solder paste, and the size of the tin powder in it is 20-38μm. So T4 solder paste is more surprising than T3 solder paste. Typically, the size of Type 3 powder may be more suitable for general electronic soldering needs, while Type 4 powder may be more suitable for specific fields that require higher soldering quality, such as automotive electronics, aerospace, etc.

Summarize

In the soldering process, selecting the appropriate size of solder paste is a key step to ensure soldering quality and reliability. Tin powder of different powder sizes has different characteristics and effects during the soldering process, so it needs to be selected according to the specific situation to ensure that the soldering quality meets the requirements. The selection of Type 3 powder and Type 4 powder needs to be comprehensively considered based on specific soldering requirements and application scenarios to achieve the best soldering effect.

If you are looking for a Chinese manufacturer of Type 3 T3 Solder Paste and Type T4 Solder Paste, please contact us. Our emails: xfsolder@gmail.com or xfsolder@163.com ; WhatsApp / Wechat is 008613450770997