Welding & Metal Fabrication: Fillers

There are many types of materials used to produce welds. These welding materials are generally categorized under the term filler metals, defined as "the metal to be added in making a welded, brazed, or soldered joint.” The American Welding Society has issued 26 specifications covering filler materials. These specifications are periodically updated and a two-digit suffix indicating the year issued is added to the specification number.

Beside national organizations, the International Standards Organization (ISO) also issues filler metal specifications. Many of the less industrialized nations utilize specifications of the industrialized countries or ISO standards. The ISO standards are available from the welding or standardization association of each country. Filler metals can be classified into four basic categories.

The next series of Connect articles will cover welding electrodes and filler metals, beginning with a brief look at the requirements for a flux.

The previous article, Part 1, dealt with the cellulosic and rutile electrodes. This article will cover the basic, iron powder and acid electrodes.

The two MMA electrode classificationschemes that will be dealt with in this month's article are the EN (Euronorm) and the AWS (American Welding Society) specifications. There is insufficient space to cover in detail the whole range of compositions for MMA electrodes so the emphasis here will be on the carbon steel filler metals.

This article looks at the wire consumables used in the gas shielded MIG/MAG, metal cored (MC) and flux cored (FC) arc welding processes.