The Grinding and Finish Treatment of Stainless Steel Surface

Most people think that stainless steel will not rust, but in fact, like many other metals, it will be oxidized and rusted when touched by hands or exposed to air and affected by the environment. In addition, after the surface of the stainless steel workpiece is processed by mechanical processing such as welding, stamping, crimping, heat treatment and so on, a black oxidized metamorphous hardened layer will be formed. And at the same time, many tiny burrs and sharp-angled burrs that are visible and invisible to the naked eye will also be formed. Unfortunately, under normal circumstances, it is difficult to remove these burrs by mechanical methods. As a consequence, the exertion of the characteristics of the workpiece material itself will be greatly influenced. In order to solve these problems, people use various methods to conduct stainless surface finish.

1. Mechanical grinding and finish:

a: grinding wheel finish; b: sandblasting finish; c: grinding finish d: extrusion finish

2. Chemical grinding and finish:

a. Electrolytic chemical grinding and finish; b. Chemical grinding and finish

3. Compound grinding and finish: the combination of mechanical and chemical grinding methods

For different metal materials, different use occasions, and different requirements for the surface of the metal workpiece, different grinding methods or a combination of several grinding methods must be adopted for grinding processing to make the processed workpiece meet the requirements of use.

Comparison between the chemical grinding and finish and the electrolytic chemical grinding and finish:

★ Chemical grinding and finish: When conducting chemical grinding and finish, we should immerse the metal in a special chemical solution composed of various components. Then the chemical energy will automatically dissolve the metal surface to obtain a smooth and bright surface.

★ Electrolytic chemical grinding and finish: When conducting electrolytic grinding and finish, we should first immerse the metal in a special chemical solution composed of various components, then the metal surface will be anodicly dissolved by current energy so a smooth and bright stainless surface finish result can be obtained.

The chemical grinding and finish is only a dipping operation, and this kind of operation is simple. However, the electrolytic grinding and finish requires large-capacity direct current, and also needs to set the current counter electrode reasonably. Moreover, it also requires the factories to accurately control the current and voltage. As a result, the operation process of electrolytic grinding and finish is actually really complicated and the quality control is difficult. Some special workpieces cannot even be processed. Thus, people have been looking forward to the emergence of better and perfect grinding methods for a long time. Although some pure chemical grinding and finish technologies have appeared during this period, the technologies that can meet important technical indicators such as gloss, environmental protection and grinding effects as electrolytic chemical grinding and finish does have never appeared.

The above are the methods that people use for stainless surface finish.