For many years carbon and graphite products have been vital tools in the electrical, electrochemical and electrothermal industries; but their wide application as corrosion-resistant materials of construction is a more recent development.
A very brief description of the process of manufacturing carbon and graphite will aid in understanding the nature and properties of the materials. The basic raw material is some form of elementary carbon, such as anthracite coal or petroleum coke. After calcining at high temperatures to drive off the volatile constituents, the basic carbon material is sized and mixed in the proper proportion of fine and coarse particles with pitches and tars. The heated plastic mass is then formed by pressure extrusion or molding to the shape and size required. The “green” piece is baked under suitable controlled conditions in a reducing atmosphere at a temperature of approximately 1800° F. During the baking process, the pitches and tars...
