How do you choose solder paste?

When choosing a solder alloy, there are four key considerations: lead content, melting temperature, alloy powder particle size, and joint strength. Lead content, melting temperature, and strength are typically addressed at the same time.

Does solder paste need to be refrigerated?

Does solder paste require refrigeration? Recommended storage temperature for solder paste is between 40°F and 50°F (4°C to 10°C). Storage at temperatures above refrigeration will reduce shelf life and voids the guarantee.

What is the difference between Type 3 and Type 4 solder paste?

Type 3 solder paste is generally considered to be the industry standard that will work for most printing applications. The use of Type 4 is really only needed for particularly fine-feature printing, where the Type 4 will produce better release and a more consistent volume deposit.

Does solder paste need flux?

Electronic boards require either ‘flux-cored solder’ for hand use, or ‘solder paste’, which is a mixture of small solder balls in a suitable flux, for machine use. This flux is likely to be too aggressive to leave on a board, and will require cleaning, otherwise it’s likely to damage the board.

What are the different types of solder paste?

By size

Type designation [IPC]	Mesh size in lines-per-inch	Particle size in μm (80% min. between)
Type 1		150-75
Type 2	-200/+325	75–45
Type 3	-325/+500	45–25
Type 4	-400/+635	38–20

What is the difference between solder flux and solder paste?

Flux, which cleans metal surfaces. Soldering paste, which allows the flowing molten solder to adhere to other metal surfaces. Solder paste (and presumably solder flux) which contains tiny solder particles or balls.

Is solder paste the same as flux?

Solder paste flux is different than liquid flux in both physical form and activity level. Solder paste flux typically contains 60-80% by weight active ingredients, compared with liquid flux’s 2-25%. By weight, a mixed solder paste commonly consists of 90% metal.

How long can solder paste sit before reflow?

This is highly dependent on the solder paste formulation. We have a few brands that can withstand 24 hours between printing and placement of components. Some grades only leave a 6 hour window. Our typical minimum specification for any new development is 8 to 24 hours for no clean paste, 8 hours for water soluble paste.

What is T3 solder paste?

“T3 solder paste, will fall through a 325 mesh screen but not through a 500 mesh screen, hence the term -325+500.” “Spheres categorized as Type 3, or T3, will fall through a 325 mesh screen but not through a 500 mesh screen, hence the term -325+500.

What’s the difference between solder paste and solder flux?

What is Flux and What is the Difference Between Flux and Solder? While solder is used to assemble components onto your circuit board, the flux is used prior to assembly to prepare and help your board through the soldering process.

Do I need flux with solder paste?

How many types of solder paste are there?

The most common solder paste powder sizes for SMT are type 3 (T3), type 4 (T4), and type 5 (T5). The lower the number, the larger the particle size within the solder powder.

How strong is solder paste?

Because it uses the ultra-find powder, the silver solder paste has a strong bond – 10x strong than typical 60/40 solder. With the microscopic size of the metal particles it creates an extremely low melting point.

Does solder paste expire?

A solder paste typically has a shelf life of 6 months when refrigerated.

How do you know if solder paste is bad?

Classic symptoms of expired paste or paste that has changed significantly from its original properties include: Significant Separation of flux and powder, Increased viscosity (leads to difficult dispensing), and in some cases large air bubble formation in the syringe.

What is the weight of the ws-820 solder paste?

WS-820 Lead Free Water-Soluble Solder Paste, SAC305, 87.5-4-M18, 600g Cartridge #153514-1998. PLEASE DO NOT HESITATE TO CONTACT THE SELLER IF YOU NEED ADDITIONAL DETAILS OF THIS PRODUCT

What is the best solder paste for LED printing?

Alpha WS-820 Solder Paste is well suited for LED applications. This world class lead free, high reliability water soluble paste offers the best in class printing, excellent resistance to BGA voids and cleanability. It is formulated to offer low voiding, ease of cleaning and print volume consistency in conjunction with air flow capability.

What is the difference between ws819 and ws820?

WS-820 was adapted from WS-819 to increase the reflow profile window. This paste will produce lower solder voiding on BGA assemblies than any other water-soluble paste that is reflowed in air.

What is the percentage of silver in solder paste?

This water-soluble solder paste contains 96.5%Tin /3.0%Silver /0.5%Copper and is halide-free. This version contains Type 4 powder which has a 20-38 micron size. (Standard Type 3 contains 25-45 micron size) Comes packed in a 600 gram cartridge.