Solder paste and things to know

In the process of soldering components and SMDs to the surface of PBC printed circuit boards, the presence of solder paste is definitely indispensable. So what is solder paste? What are the composition and features of this solder cream? Follow the article below to find out!

Learn about solder paste 

What is solder paste? 

Solder paste is known to be a mixture of solder paste and specific fluxes in a certain ratio. As the name suggests, this mixture is in the form of a wet cream. This will help the solder paste more easily adhere to the surface of the printed circuit board than other solder materials such as solder sticks or solder.

Composition of solder paste 

Usually, traditional lead solder paste will contain ingredients including 2 metals, Tin (Sn) and Lead (Pb) with a ratio of 63% Tin and 37% Lead. This is the standard leaded solder paste ratio, for a shiny, bright, beautiful, and durable weld.

However, later on, the laws of some countries banned the use of lead. Because lead is a toxic element, dangerous to human health. So the composition of the solder paste has changed. Accordingly, lead metal will be replaced by other metals such as Silver (Ag) and Copper (Cu). The ratio of lead-free solder paste is also very diverse, can be 99.7% Tin and 0.3% Copper or 96.5% Tin, 3% Silver, and 0.5% Copper.

Features of solder lead cream 

Compared with solder wire, or stick form, solder paste has more outstanding features, such as:

High viscosity, good adhesion, and absolutely safe for users’ health.

Outstanding continuous printing ability, minimizing error conditions.

Good corrosion resistance, high dielectric strength, and thermal shock resistance.

How to use the correct solder paste 

First, take the solder paste and apply it to the printed circuit board and only apply it to the areas to be soldered. In order for solder paste to be properly applied, a PCB stencil is required.

A stencil will be placed on the board and applied a layer of solder paste to ensure the correct amount of solder in the positions to be soldered. Note that it is necessary to apply enough solder paste. Too little cream will not be enough to make a weld. If it is too much, the weld will be stuck between adjacent pads.

After applying solder paste on the printed circuit board, the circuit board will be put into the machine to place the components. The solder paste’s tension will help hold components in place temporarily. Care should be taken not to hit the board hard during this stage as it may cause the components to fall out. In addition, the board needs to be soldered within a few hours after the components have been put in, otherwise, the solder paste will be less effective when left in the environment for too long.

Application of leaded solder paste 

Leaded solder paste is used as a solder paste for PBC-printed circuit boards used mainly in Reflow Soldering and Surface Bonding Technology (SMT). Solder paste makes the manufacturing process simpler and easier. At the same time, it also saves a lot of time and money for businesses.

Address to buy reputable and quality solder paste 

The demand for using solder paste is huge, leading to many addresses providing this material. Make customers not know where to sell reputable and quality products.

Currently, Thetech is known as a supplier of genuine standard solder paste with the best prices in the market. Our products are guaranteed for origin, product quality, and price. so you can rest assured when buying from us.

Above is a summary of all information about solder paste. Hopefully, this article has helped you understand more about this type of solder. If you have any questions, do not hesitate to contact Thetech for advice and support from our staff!