It seems recently there has been more talk about the advantages of an isotropic, non directional finish on machined surfaces obtained through a chemically accelerated vibratory process. It isn’t necessary to utilize a chemically accelerated chemistry to achieve an isotropic finish. The vibratory finishing process is what is producing the isotropic non directional finish which reduces or eliminates the surface stress on machined components. The addition of a chemical accelerant to the vibratory process has actually increased the use of vibratory finishing as a means to produce very smooth finishes because it drastically reduces the time required to achieve this finish.
Products Finishing Magazine features Precision Finishing Inc.
What is Isotropic Finishing? Webster’s definition of isotropic is “exhibiting properties with the same values when measured along axes in all directions”.
Since its evolution the vibratory finishing process has produced an isotropic non directional finish which improves the surface finish and edges of machined components. The manufacturing process inherently creates stress risers and vibratory finishing reduces or removes them. This improved isotropic surface enhances any subsequent final finish in addition to increasing the overall strength and condition of the component due to the relief of the surface stress.
The beauty of vibratory finishing is it provides a repeatable, non directional, uniform finish from part to part at a very reasonable cost. It is widely recognized as the first step to finishing a component requiring deburring, radiusing and/or micro surface improvement. There are tremendous advantages to applying an isotropic finish to the surface of a part, however most people see deburring as the biggest or only advantage to vibratory finishing.
So where does this chemically accelerated vibratory process fit into isotropic surface improvement and what is its’ true advantage over the conventional vibratory process? Since it is a vibratory process it inherently produces an isotropic non directional surface finish and therefore provides the benefits of removing stress from the surface of the part. However, these accelerants have dramatically reduced the time to achieve very low surface finishes without heavy metal removal and radiusing of the part.