Description
ER 312 filler wire is widely regarded as an outstanding welding consumable due to its excellent performance, reliable operating characteristics, and weld metal of carefully controlled chemical composition. It is specifically designed to produce a highly crack-resistant weld deposit, making it an ideal choice for demanding applications where conventional filler metals may fail. The weld metal exhibits exceptional resistance to cracking and fissuring, even under conditions of high restraint, dilution, or thermal stress.
One of the key advantages of ER 312 filler wire is its ability to weld dissimilar and unknown base metals successfully. Its high alloy content and fully austenitic structure with a controlled amount of ferrite provide superior tolerance to variations in base material composition. As a result, it is frequently used in repair and maintenance work where the exact metallurgy of the component cannot be easily identified.
Typical applications include the welding and rebuilding of leaf and coil springs, gear teeth, forged shafts, earth-moving equipment, and a wide range of industrial machine parts. It is also commonly employed for joining carbon steels to stainless steels, as well as for hard-to-weld steels that are prone to cracking. The high strength and toughness of the deposited weld metal contribute to improved service life of repaired components, particularly in heavy-duty and high-impact environments.
However, the use of ER 312 filler wire should be limited to applications with service temperatures below 420 °C. Exposure to higher temperatures may lead to the formation of a secondary brittle phase, which can adversely affect mechanical properties and reduce the toughness of the weld metal. When used within its recommended temperature range, ER 312 filler wire delivers excellent performance, durability, and reliability, making it a preferred choice for challenging welding and repair applications.


