OVERVIEW

Mass finishing compounds are added to parts and media to increase deburring action (i.e., to add a more aggressive environment); remove scale and heat treat tints; scour surfaces; and clean parts, media, and tubs. In addition, compounds modify the luster or color of the workpieces. They add corrosion-inhibiting coatings for steels, aluminum, and zinc. In some, the abrasive in the compound may be used primarily to keep flat parts from sticking together.

Most compounds are combinations of chemicals that dissolve in water and form solutions to maintain consistency or to modify the action of media against the workpieces in mass finishing. Compounds come in premixed liquids or in powder form. Some compounds contain non-soluble abrasives for special applications, such as part-on-part finishing. The use of too little, too much, or an improper compound can adversely affect the cycle time and/or ability of the media to perform as intended.

Generally, good compounds include: water, water conditioners, cleaners, wetting agents, lubricants, foam control agents, pH buffers (pH control chemicals), rinse agents, suspension agents, and emollients. Some also contain metal brighteners and corrosion inhibitors. In more technical terms that will be discussed later they also may include: sequestrant, builder, detergent, coupling agent, abrasives, foam control material, lubricity control material, soil anti-redeposition agent, coloring agent, bleaching agent, and descaling agent. The list of chemicals is extremely long and the amounts of chemicals used vary almost as much as the variety of chemicals, depending upon the results desired and the economics of the manufacturer...