
Nearly every aspect of heavy industry depends on connections. These elements hold everything together, particularly within the context of delicate microelectronic items that are small in stature but big in reliability and performance, especially in mission-critical applications and the harshest of environments.
Solder Preforms provide a strong and effective bond – a metallic glue, if you will between the raw circuitry and elements within an electronic package and any covering at the top namely, a lid. The development of Solder Preforms is a huge innovation within our industry. How are they made? Solder Preforms are made of solder alloys customized into shapes and dimensions specific to an application.
Microstamped pieces of foil take the shape that matches solder joints, optimizing soldering distribution in a precise manner. The size of a preform is determined by the volume of solder needed. Preforms are preferred for precision applications due of the uniform volume, consistency, and adhesion it delivers to the joint.
Choosing The Right Alloys
What is an alloy you may ask? An alloy can be described as a mixture of one metal with one or more other metals. Alloys result from a melting process that allows the materials to fully mix before cooling and solidification at room temperature.
Alloys are the main component of Solder Preforms because of the enhanced properties they can provide, such as strength, hardness, machinability, and resistance to corrosion. COINING uses a variety of alloys specific to customer’s needs. COINING’s decades of experience working with metals assure customers of high quality and efficient Solder Preforms.
COINING works efficiently with silver, gold, tin, lead, antimony, indium, copper, molybdenum, iron, nickel, Kovar and tungsten. Special alloys can also be used that include palladium, germanium and platinum. Our metallurgists also work with additives like phosphorus, silicon, and gallium if needed.
All our customers need to do is specify the end material properties, and our metallurgists will do the rest! We will find a standard alloy or design a custom alloy to meet the application need. COINING’s vast experience with both lead-containing and lead-free solders provides customers with the widest range of options.

We All Come in Different Shapes and Sizes Just Like Solder Preforms
Solder Preforms come in a variety of standard shapes e.g., rectangles, squares, discs or frames, and sizes as required by customers. COINING can customize preform geometry for any application.
How do we choose our alloys? They are chosen for an application based on melting point, physical properties and strength. A key consideration is the soldering temperature and the operating temperature of the component being soldered. One common rule to keep in mind is to select an alloy that has a melting point at least 50°C higher than that of the operating temperature of the part being joined.
Another factor when determining size and shape of a Solder Preform is the location of the solder joint and the volume of solder needed. For flat dimensions, the design engineer will first determine the diameter, width, and length. Once this is determined, the thickness can be determined. For through hole components, 10%-20% is typically added to the volume. Pad to pad joints can have 5% less of the surface area.
The burr tolerance of each Solder Preform is also important to clarify, and this should ideally be close to standard tolerances to minimize added cost and lead time in manufacturing. COINING has a wide experience and an array of standard shapes and sizes that customers can choose from which minimizes lead time.
Solder Preforms Applications
Solder Preforms are used in a wide range of industries — from small lighting products to robotics, the utilization of this product varies widely.
In the electronics industry, attaching a through-hole component to a mixed board is no longer a difficult and costly process. Placement of a solder paste near or over a through-hole is one method that manufacturers have tried but this can be challenging due to spillage or inconsistency of volume.
With Solder Preforms, this is no longer the case.
Solder Preforms find their homes in many different but essential applications:
- Medical devices
- Aerospace applications
- Lighting products
- Navigation-related equipment
- Defense applications
- Communication devices
Miniaturization of Mobile Phones
Many people have never thought about how mobile or smart phones are assembled. If it works that’s all that matters right? It’s fascinating to learn about the innerworkings of a device you use so often. These communication devices are becoming smaller and smaller, and the manufacture of these devices is made possible in part by new technologies for joining these increasingly small components.
The miniaturization and functionality of mobile phones make it unmanageable to print enough solder paste to electronically connect shields to the pads. Solder Preforms are a solution to such solder-starved conditions. In these processes, the preforms are positioned by component placement machines to provide precision volumes of solder exactly where it is needed. This makes the Solder Preforms the best functional solution.
Terminal Capacitors
Capacitors are devices that store electrical energy. This is a passive electrical component with two terminals. The terminals are connected mechanically and electrically using solder. If a capacitor terminal solder connection is imperfect, it can have defects and be prone to disfunction. In some cases, Solder Preform use has reduced defects by 95%.
Solder Preforms Applications
Solder Preforms find themselves in all different types of applications. Solder Preforms have been used in applications from fire sprinkler systems to aircraft engines. The initial MIM 104 Patriot Guided Missiles that became operational in 1984 had components soldered by these preforms. The ground-based radar programs made use of the product as well. How cool!
In the medical field, Solder Preforms are utilized in the manufacture of implants and heart pacemakers. They are an economical solution to solder-starved assembly applications. Consult a COINING engineer to make sure that the right Solder Perform best suits your application.
Benefits of Using Solder Preforms
Solder Preform benefits include increased efficiency and productivity. Since preforms are accurately made solder shapes with an exact volume of solder for an application, it delivers the precise solder to the right location.
This product minimizes, if not eliminates, manual processes in assembly, inspection time, and clean up after production. This cuts down production costs which is big consideration for many customers.
Preforms may be the only method to solder hard to reach joints.
The miniaturization of components for mobile and smart phones, medical devices, and aerospace applications rely more and more on Solder Preforms. Solder Preforms provide a more reliable and quality alternative compared with hand soldering. Preforms are a better method when compared to hand soldering with flux cored wire.
Optimized alloys and mechanical design of Solder Preforms results in the best manufacturing efficiency. Low melting point preforms are usually used to strengthen other joints formed in an assembly. High temperature preforms are used if a manual soldering assembly is being produced prior to conventional surface mount technology (SMT) or wave soldering.
Technical Specifications of Solder Preforms
There has been a major shift in the electronics industry — the shift to lead-free compliance a directive by Restriction of Hazardous Substance. In February 2003 RoHS was implemented by the European Union, with an update in 2015, that included four new organic compounds plus exemptions for specific applications.
It stipulated that all electronics sold to member countries must comply with this directive. The restricted substances include lead, mercury, cadmium, chromium VI, PBB, PBDE, DEHP, BBP, DBP and DIBP.
COINING works with customers to ensure compliance with regulations and offers a wide range of lead-free Solder Preforms. Our metallurgists can also blend alloys specific to customer needs. We have hundreds of custom-blended alloys and can create new ones for unique applications. Such alloys are suited for extreme environments and temperatures, with eutectic and non-eutectic melting points above 1000 °C.

Handling
Solder Preforms are not only soft metals, but they can be small. It is important that no damage or scratches are made after the manufacturing process. Excessive scratches on the surface area may result in the formation of high levels of oxide. Improper handling can cause performance inefficiency. Protective gloves, such as Nitrile rubber, should be used to avoid contamination.
Shelf Life of Preforms
Like the food in your pantry, Solder Preforms should not be left on the shelf forgotten about. For the best results they should be used within 1 year, preferably less. This is dependent on the application, handling during transport, and storage.
As a rule, storage conditions to be free from outside contaminants and reduction of oxidation that may occur if stored for longer periods of time. Stored properly, Solder Preform shelf life can vary from just a few weeks to several years.
Packaging and Storage
Preforms should be stored in its original packaging and should not be opened until it is time for the application process. Solder Preform packages or boxes should be stored in a dry, clean, and cool environment.
COINING at a Glance
COINING is a world-class manufacturer of micro components that have a big impact on people’s lives. From sensors and satellites to implantable electronics, our high-performance metal products operate in a vast range of mission critical applications worldwide.
For people who demand precision, flexibility, and speed, COINING is the market leader in custom alloys, microstampings, and Solder Preforms. COINING also offers specialized bonding wire, precision thermal management materials, and hermetic solutions.
In fact, we’re the largest Solder Preform manufacturer in the world. With a broad range of products, the most extensive library of preform dies in the industry — about 15,000 different tools — and our very own COINING labs to make custom alloys, we can move faster to market than our competition.
Regardless of what you’re looking for, we’re your go-to team for high-performance, high-precision components custom-designed to meet your unique needs.
COINING is part of the Components & Wire division of AMETEK Inc., a leading global manufacturer of electronic instruments and electromechanical devices with annualized sales of approximately $5.5 billion.