Conductive epoxy is a resin that is used to coat and bond electrical parts. It is a strong structural adhesive used in the electronic industry. What makes this epoxy conductive are the materials utilized to synthesize it, such as silver or nickel.
In 1966, Epoxy Technology, Inc. became the first company to supply conductive epoxy to the manufacturing industry. The company intended the product be used as a die-attach adhesive for nanoelectronics and semiconductor assembly and packaging, and it is still used for these purposes today. Frank W. Kulesza, the president of Epoxy Technology, was the first to come up with the original design.
One type of epoxy that is particularly adhesive and electrically conductive is silver conductive epoxy. When used as an engineering adhesive, it is effective in repairing defects in metal designs and creating circuit board jumpers. Silver conductive epoxy is very tensile, able to withstand 911 pounds per square inch (63.77 kilograms per square centimeter). It can handle a compressive pressure of 1,100 pounds per square inch (77 kilograms per square centimeter) before rupturing. Most importantly, it is very low in electrical resistance, carrying a volume resistivity at 25° Celsius (77° Fahrenheit) of 0.38 ohm-centimeters.
Epoxy application involves using this powerful adhesive to bind not only metals such as bronze, brass, copper, steel, and aluminum, but also standard construction materials such as wood, paper, plastic, fiber, rubber, and glass. Binding metals together is especially important in the electrical and high technology manufacturing industries. Adhering paper, plastic, and the like to a surface is typically used in industries that would otherwise employ traditional soldering methods, such as woodworking and home construction.
Cure time, or the time it takes for the conductive epoxy to be fully operational, is an important property of this material. A standard air cure time, assuming that the surrounding environment stands at 24° Celsius (75° Fahrenheit), is five hours. Typically, the instructions that come with the material encourage the user to warm the epoxy before application. Heat cure time differs with the temperature applied but is usually within the range of five to 15 minutes.
Most conductive epoxies are available as a set of two 7 gram tubes. They may also come in pre-weighed, sealed pouches that can be easily sent by mail. Many online shopping portals offer these epoxies. In addition, epoxy can be bought online from one of the popular epoxy manufacturing companies.