The solder flux market now predominantly features high-volume fluxing agents. These fluxes are formulated explicitly for high-volume machines where entire printed circuit boards (PCBs) are fluxed before soldering or reflow. While these liquid fluxes are perfect for high-volume processes, they cause many problems when used in localized soldering tasks. When technicians are targeting single components for rework, removal, or replacement, such liquid fluxes act very problematically. The liquid nature of these production fluxes makes it impossible for soldering professionals to control localized prototyping processes and rework applications. The liquid fluxes typically spread very quickly all over the printed circuit boards, making huge messes.
Table of Contents
Understanding Flux Solder
Flux is used to eliminate surface oxides, grime, and dirt from metal surfaces. The main goal of this component is to boost the quality and the strength of intermetallic bonds. Flux is typically used with solder bars or solder wires to clean and prime metal surfaces before soldering. Any electronic equipment manufacturer who wants high-quality PCB Rework Services must be aware of the type of electronic flux their providers use. The electronic flux activity will indicate just how effective it is at removing surface contaminants.
If wrong flux solder is used to rework your PCBs, it’ll lead to unnecessary expenses and delays. The last thing an electronic equipment manufacturer needs is to keep a huge number of circuit boards in “Work in Progress” mode. Unable to reach the final markets, PCBs that need to be reworked cause a lot of trouble for electronic equipment manufacturers, especially in the computer and telecom sector, where the life cycles of electronic products become shorter every year.
Successful electronic equipment manufacturing companies are starting to realize that outsourcing rework tasks to specialists are the best way to avoid these unnecessary delays and expenses. These rework specialists know what types of solder fluxes to use for specific rework processes. Given that the solder flux market was valued at over $235 million in 2019, these rework specialists have plenty of choices while selecting soldering fluxes. Plus, the surging demand for PCBs is expected to expand the solder flux market further. Here are the most common types of electronic fluxes that PCB rework specialists use –
Common Types of Electronic Fluxes Used by Top PCB Rework Specialists
The electronic or soldering fluxes used in modern-day electronics manufacturing processes are classified on the basis of their electronic activities and constituents. These two factors determine a soldering flux’s ability to remove surface contaminants on PCBs effectively. The most common types of solder fluxes that PCB rework specialists currently use include –
Extracted from pine tree barks, this natural soldering flux comes in three varieties – Rosin Activated Flux (RA), Non-Activated Rosin Flux (R), and Rosin Mildly-Activated Flux (RMA). Although the general formula of this soldering flux is C19H19COOH, its composition varies from batch to batch.
- Non-Activated Rosin Flux (R) is ideal for soldering surfaces that contain minimal amounts of oxidants and are generally clean.
- Non-Activated Rosin Flux (R) is best suited for soldering copper wires, semiconductors, and pretty much all hand-soldering jobs. So, electronics manufacturers who want their PCBs to be manually reworked or re-soldered must ensure that their rework experts are using Non-Activated Rosin Flux (R).
- Rosin Mildly-Activated Flux (RMA) offers better cleaning results than Non-Activated Rosin Fluxes (R). These fluxes are suited for PCBs that contain high amounts of lead.
The Occupational Safety and Health Administration (referred to as OSHA) formed the Hazard Communication Standard (HCS) in 1985. Since then, the use of soldering materials that generated potentially harmful solder fumes has been banned in pretty much all industrial sectors (not just the electronics manufacturing sector). Since these bans, the use of No-Clean Fluxes has become increasingly popular across the world. Besides being safer, less harmful, and more reliable than Rosin Fluxes, No-Clean Fluxes also help rework specialists cut down cleaning costs. The floor space required to work with No-Clean fluxes is also minimal. This flux is also known as low-residue electronic solder flux.
Organic Acid Solder Fluxes
Organic Acid Solder Fluxes are more efficient and stronger than Rosin Fluxes. Also referred to as water-soluble fluxes, Organic Acid Solder Fluxes are frequently used to rework, repair, or re-solder mixed assemblies (type II and III in particular). These assemblies are commonly used for manufacturing devices for the military and for manufacturing various commercial electronic goods. Bear in mind – this solder flux is water-soluble. So, make sure your PCB rework experts dry the assemblies completely before applying any power to them.
Choosing Rework Specialists
Now that we know the different types of solder fluxes top providers of circuit board rework services use let’s see what qualities electronics manufacturing companies should seek from these providers –
- Reliability: Whenever there are engineering change orders, product upgrades, or any other issue in the manufacturing process, efficient PCB rework services are mandatory. So, partnering with a PCB rework expert who can reliably fix complex packages and assemblies is vital for all OEMs.
- Experience: OEMs that create in-house rework centers have to spend a lot to give their rework specialists access to proper equipment, training, and constant engineering support. That’s why outsourcing rework-related responsibilities to experienced PCB rework experts who have extensive backgrounds in circuit board rework services is a much better option.
OEMs must find experts in rework/repair processes and make sure they use the right types of solder fluxes while doing their jobs!