Defoamer Theory and Selection for Aqueous Metalworking Fluids
Foam can be problematic in aqueous metalworking fluids causing issues in process or performance. Even without direct system impact, the presence of foam can result in a negative perception of system quality. Ideally, an aqueous fluid would be completely free of foam throughout its working life, but this is a difficult goal to achieve and requires extensive formulation development and testing. In order to minimize this work and find the best solutions more quickly, it is important to consider the root causes of foam, what mechanisms are available to reduce or eliminate it, and the nature of defoaming additives used to prevent foam during fluid use.