We are Apogeeweb Semiconductor Electronic

WELCOME TO OUR BLOG

Home arrow PCB arrow Types of pcb soldering-The differences between Wave Soldering, Reflow Soldering, and Selective Soldering

arrow left

arrow right

Types of pcb soldering-The differences between Wave Soldering, Reflow Soldering, and Selective Soldering

Author: Apogeeweb
Date: 19 Sep 2022
 318
PCB Soldering Material

What is the soldering?

What is the PCB soldering?

Video about the pcb soldering

PCB Soldering Material

Types of Soldering

Types of PCB Soldering

What is the Wave Soldering

Wave Soldering Progress

The advantages and disadvantages of wave soldering

What is the Reflow Soldering?

Reflow Soldering Progress

The advantages and disadvantages of Reflow Soldering

What is the Selective Soldering?

Selective Soldering Progress

The advantages and disadvantages of Selective Soldering

Wave Soldering VS Reflow Soldering

Selective Soldering VS Wave Soldering

Reflow Soldering VS Selective Soldering

The conclusion of Wave Soldering VS Reflow Soldering VS Selective Soldering

PCB Soldering FAQ

 

What is the soldering?

Soldering is the process of putting metal parts together with melted solder, a metal having a lower melting point than other metals. It is a process that is essential to the electronics industry and the main way to connect electrical components. Soldering is utilized in the construction of printed circuit boards (PCBs), as well as in the manufacture of jewelry, pipes, and plumbing. When soldering, a soldering iron or gun is used with solder at a temperature of less than 840 degrees Fahrenheit. Solder typically appears as a thin wire or tube. A flux-like acidic mixture is present inside the tube to stop oxidation.

Despite the fact that there are many various kinds of solder, it is often an alloy of lead or tin, brass, or silver that is made to have a low melting point. This metal is melted by the soldering iron and then used to adhere components together rather like glue. The solder metal will re-harden into a single, substantial form that joins the two pieces as it cools. There are currently various lead-free solder options available in an effort to reduce lead usage due to environmental and safety concerns. These substitutes frequently consist of brass, copper, tin, or silver. Lead-free solder can be less effective than conventional solder and has a greater melting point.

Soldering

What is the PCB soldering?

Soldering electrical circuit boards is also referred to as PCB soldering. One of the most fundamental skills for everyone who wants to deal with electronics and electrical circuits is this kind of soldering. The most fundamental definition of the soldering process is that it is a technique of attaching two little components together on the surface of the PCB, which is an abbreviation for Printed Circuit Board. There are many various ways you can finish the soldering process. To join two or more separate electrical components on your circuit board, in other words, soldering is a technique.

The soldering action itself is pretty straightforward at its heart. A soldering iron, some solder, and the materials you are joining together are all you need to execute the simplest soldering task. A soldering iron is a tool that melts solder and is used to connect two pieces together. It resembles a pen and gets quite hot.

Despite the fact that there are many various kinds of solder, it is often an alloy of lead or tin, brass, or silver that is made to have a low melting point. This metal is melted by the soldering iron and then used to adhere components together rather like glue. As the solder metal cools, it will re-harden into one large shape that connects the two parts.

Pcb Soldering

 

Video about the pcb soldering

Video Description: How to solder a through hole connection on a printed circuit board (PCB).

 

PCB Soldering Material

Choosing the correct sort of solder can seem like a daunting chore for a rookie designer or assembler because there are so many different varieties on the market. By enabling the molten, soft alloy solder to produce a eutectic that fuses as it cools, solders are used to create electrical connections between metal contacts. A soldered PCB's mechanical strength after solidification, the needed melting temperature, and any fumes released during soldering will all depend on the combination of metals used to build it. By looking at the core material, metallic components, and soldering flux kinds, we can distinguish between various PCB soldering materials. Lead-based filler metals, such as lead patch, were originally used in patching, however because to regulations, lead-based filler metals are gradually being replaced with lead-free fastens. These may consist of the following metals:

  • Brass
  • Copper
  • Antimony
  • Tin
  • Indium
  • Silver or bismuth

 

Types of Soldering

  • Lead-free solder
  • Lead-based solder
  • Flux-core solders
  • Silver alloy solder

 

Types of PCB Soldering

  • Wave Soldering
  • Reflow Soldering
  • Selective Soldering

 

What is the Wave Soldering

Electronic components are attached to a printed circuit board (PCB) using the large-scale soldering technique known as wave soldering. The name comes from the method of attaching metal components to the PCB by applying waves of hot solder. The components are inserted into or placed on the PCB, which is then passed over a pumped wave or cascade of solder. The technique employs a tank to contain an amount of molten solder. A reliable mechanical and electrical connection is made when the solder wets the exposed metallic portions of the board (those not covered by solder mask, a protective layer that stops the solder from bridging across connections). The process is much faster and can create a higher quality product than manual soldering of components.

Surface mount and through-hole printed circuit assemblies both use wave soldering. In the latter instance, before being subjected to the molten solder wave, the components are first attached to the printed circuit board surface by the placement apparatus.

Wave Soldering

 

Wave Soldering Progress

It is essential that an electronics printed circuit board be produced and designed correctly in order to process it properly using a wave soldering equipment. It contains two steps to wave soldering progress.

Step One Solder resist layer: The first is now considered best practice for board design. The PCB design incorporates a solder resist or solder mask layer, which provides a layer of "varnish"-like material to the board and prevents solder from adhering to it. Only the necessary parts for soldering are left exposed. The color of this solder resist is most frequently green.

Step Two Pad spacing: The second major precaution is to make sure there is enough space between the solder pads that need to be soldered. There is a chance that the solder may bridge the two pads if they are too close together, leading to a short circuit.

 

The spacing requirements for wave soldering depend on the orientation of the board in relation to the solder flow because the solder wave is created by solder flowing out of the reservoir tank as the board passes over it. Pads that are separated from one another perpendicular to the solder flow should have a wider separation than those that are separated perpendicular to it. This is due to the fact that solder bridges are considerably more likely to form in the direction that solder flows.

 

The advantages and disadvantages of wave soldering

The advantages of wave soldering

  • No glue is needed to secure components during reflow soldering.
  • Board areas where no soldering is required do not have to be masked off.
  • Soldering machines that conduct selective soldering are generally cheaper to operate.
  • Parameters for each are variable and can be more finely controlled.
  • Allows wave soldering to be applied to boards with SMDs and vias.
  • Suited for PTH assembly
  • Is more time-saving than hand soldering
  • More affordable
  • Less prone to PCB warpage
  • Provides strong solder joint quality

 

The disadvantages of wave soldering

  • High solder consumption
  • High flux consumption
  • High power consumption
  • High nitrogen consumption
  • An increase in post-wave solder rework
  • Masking of sensitive areas on PCB assemblies
  • Cleaning of wave solder aperture pallets or masks
  • Cleaning of soldered assemblies

 

What is the Reflow Soldering?

Although reflow soldering differs slightly from wave soldering, it is still the most used method for joining surface mount components to a circuit board. For soldering through-hole components, wave soldering is more frequently utilized. Reflow soldering can be used for this purpose, however it is rarely done because wave soldering is more affordable.

Reflow soldering is the process of attaching components to contact pads by creating a solder paste from powdered solder and flux. The solder is then melted and the junction is connected by heating the entire assembly in a reflow oven or under an infrared lamp. If necessary, you might use a hot air pencil to solder each individual link.

Reflow Soldering

 

Reflow Soldering Progress

There are numerous separate steps that make up the reflow process itself. These are necessary to make sure that the board is heated to the appropriate degree for reflow soldering without causing any excessive amounts of thermal shock. The greatest quality solder junctions are produced when the temperature of the reflow tunnel or chamber is properly profiled. These are the four steps that are typically employed:

Preheat: The boards must gradually warm up to the necessary temperature. The board or the components could be harmed by the thermal stress if the rate is too high.

 

Thermal soak: The board then enters what is frequently referred to as a thermal soak area after being brought up to temperature. For two reasons, the card in this case is kept at a certain temperature. One is to make sure that any spaces that aren't heated enough due to shadowing effects are brought up to the necessary temperature. The other is to eliminate the solvents or volatiles from the solder paste and to activate the flux.

 

Reflow: The soldering process's reflow area is where the maximum temperature is reached. The solder is made to melt and form the necessary solder joints here. The real reflow procedure involves the flux lowering the surface tension at the metal-to-metal contact to achieve metallurgical bonding, which enables the melting of the individual solder powder spheres.

 

Cooling: After reflow, the boards need to be cooled, but it needs to be done without stressing the components. Excess intermetallic development and thermal shock to the components are prevented by proper cooling. The cooling zone typically has temperatures between 30 and 100°C (86 and 212°F). The temperature in this zone causes a relatively quick cooling rate, which is selected to give the solder a fine grain structure for the structurally soundest union possible.

 

The advantages and disadvantages of Reflow Soldering

The advantages of Reflow Soldering

Trusted by many manufacturers

Best suited for SMT assembly

Effective for numerous SMT package types in a single process

Easy to monitor and control

It is a less wasteful method when dealing with specific parts of a PCB

 

The disadvantages of Reflow Soldering

For those seeking to enhance certain aspects of the convection reflow soldering process, the use of nitrogen can be the key. But the use of nitrogen may be expensive.

The temperature thresholds of the PCB assembly and the unique requirements of the solder paste must be taken into account while creating the reflow soldering profile. Accurate profiling must be obtained in order to be effective.

 

What is the Selective Soldering?

For THT and mixed technology soldering applications, selective soldering, commonly referred to as mini-wave soldering, provides economical, consistent outcomes. Individually programmable and monitored soldering spots are used to regulate flux quantities and soldering time. Additionally, it is the only technique that can be repeated to solder THT components onto a two-sided PCB assembly.

Selective Soldering

 

Selective Soldering Progress

Step 1: Fluxing or the application of liquid flux.

Step 2: Preheating of the PCB assembly.

Step 3: Soldering with a site-specific solder nozzle.

 

The advantages and disadvantages of Selective Soldering

The advantages of Selective Soldering

  • Secure and fast process optimization
  • Reliable solder joint creation without overheating components
  • Guaranteed process repeatability
  • The elimination of expensive wave solder pallets
  • The ability to solder around tall parts with tight spacing
  • The ability to solder dense concentrations of THT pins

 

The disadvantages of Selective Soldering

  • Since each circuit board must have a customized program, the technique is time-consuming and not well suited for mass production.
  • As there are several parameters, processing problems may occur.

 

Wave Soldering VS Reflow Soldering

How do you decide which soldering technique to employ when? Pad shapes, how much time you have, component orientations, the type of printed circuit board, and other variables could all play a role. Wave soldering is more difficult in several aspects. Careful observation is required for factors like board temperature and the length of time the board is in the solder wave. Board flaws are far more likely to occur when the proper wave soldering environment is not created.

When you use reflow soldering to create your printed circuit boards, you won't have to worry nearly as much about protecting the environment. Even yet, wave soldering is frequently more expedient and less expensive than reflow soldering. It is frequently the only feasible method of soldering a board. Reflow soldering is frequently employed for smaller-scale manufacturing projects that don't call for a technique that can be used for quick, low-cost mass production.

Remember that in some circumstances you might be able to employ both reflow soldering and wave soldering. It is possible to wave solder components after reflow soldering them on one side. Additionally, you can always manually solder or hand solder PCB components, but if you have access to one of the mechanical techniques of soldering, this will rarely be a suitable strategy. Reflow soldering is still significantly superior, and manual soldering is simply a substitute for it.

 

Selective Soldering VS Wave Soldering

When it comes to Printed Circuit Boards with through-hole and bigger surface mount components, wave soldering is the best technique. On the other hand, selective soldering is advantageous for a densely populated board since it enables the consideration of a lot of factors. However, because it necessitates the development of a special program for every circuit board, it is inappropriate for mass production.

 

Reflow Soldering VS Selective Soldering

When producing a circuit board, through-hole components require the use of a selective soldering machine. Reflow is only suitable for SMT components because it only solders the board's top surface. However, all sides of through-hole components need to be soldered.

Fewer businesses are using selective soldering for component assembly due to the high production capacity and ease of reflow oven soldering. There are simply too many benefits to ignore. Reflow ovens have replaced hand soldering as the predominant method of PCB assembly in the industry, whereas selective soldering was formerly far more common. In a given amount of time, a reflow oven can produce many more units.

The assembly process is also made simpler. A solder ball (often a mixture of solder and flux) is deposited at the location of the joint after the components have been positioned on the board. The solder starts to flow plastically and form the solder junction when the board is conveyed through the oven. The board exits the oven and can either be used in the product of which it is a part or it can be transported to the person who will use it before the end user. Component assembly takes longer using selective soldering machines. They usually cost more money. Furthermore, assembling a lot of PCB designs doesn't need for intricate soldering. Reflow is frequently used by component manufacturers rather as selective soldering for this very reason.

 

The conclusion of Wave Soldering VS Reflow Soldering VS Selective Soldering

Wave soldering is more challenging in various respects and close inspection is required for elements like board temperature and the amount of time the board remains in the solder wave, while Environmental preservation won't be a major concern when you employ reflow soldering to make your printed circuit boards. What’s more, wave soldering is frequently more expedient and less expensive than reflow soldering. So if you want to take the cost and environment into account, the wave soldering must be the best choice.

Wave soldering is the optimum method for Printed Circuit Boards with through-hole and larger surface mount components. However, because selective soldering allows for the evaluation of numerous variables, it is favorable for a board that is densely packed. But selective soldering is not suitable for mass production, though, as it calls for the creation of a unique software for each circuit board.

Due to the great production capacity and simplicity of reflow oven soldering, fewer companies are adopting selective soldering for component assembly. When employing selective soldering machines, component assembly takes longer. They typically have higher prices. Furthermore, complex soldering is not necessary for the assembly of many PCB designs. For this exact reason, component manufacturers commonly use reflow instead of selective soldering.

 

PCB Soldering FAQ

What is the PCB soldering?

Your circuit board is the PCB. As you use your soldering equipment to connect various components and terminals to one another and to the board, all of the soldering you conduct will occur on the surface of this board.

 

What are the 4 types of soldering?

Lead-free solder, lead-based solder, and flux-core solder are the three primary varieties of solder. The silver alloy solder is a different variety. These kinds are created using alloy composition. Other solder kinds exist as well, depending on the form, core type, and application.

 

What is the difference between reflow soldering and wave soldering?

There are two soldering methods that are completely distinct from one another: wave soldering and reflow soldering. In wave soldering, the components are joined together with the aid of a melted solder wave crest. Components are soldered using reflow, which is created by hot air, in reflow soldering.

 

What is the difference between selective soldering and wave soldering?

In contrast to wave soldering, which strikes all solder joints simultaneously, selective soldering progressively solders individual components using a local wave on an x-y gantry. However, additional benefits have made selective soldering the method of choice in many circumstances.

 

What are the advantages of wave soldering?

Components are held in place during reflow soldering without the use of adhesive. No need to mask off board sections that don't need to be soldered. Selective soldering equipment are typically less expensive to run. Each has adjustable parameters that can be more precisely regulated.

Best Sales of diode

Photo Part Company Description Pricing (USD)

Alternative Models

Part Compare Manufacturers Category Description

Ordering & Quality

Image Mfr. Part # Company Description Package PDF Qty Pricing (USD)

Related Articles

pinglun

Leave a Reply

Your email address will not be published.

 
 
   
 
code image
Rating: poor fair good very good excellent

# 0 1 2 3 4 5 6 7 8 9 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z