Final Polishing Suspensions

 

New additions:

Aluminum oxide polishing agents for metallic and nonmetallic materials such as Plastics,
1 µm
pH: 3.4  
Package sizes: 1 liter and 5 liter

Silica-Final Polishing Suspensions

By the final polishing of certain materials, especially metallic type, silica suspensions have displaced the alumina suspensions. This is mainly due to the different hardness, because silica has a Vickers hardness of 1100 HV, Alumina in contrast, approx. 1800 HV. For the polishing of e.g. ceramic materials you prefer usually diamonds.

We have a large range of Silica – suspensions. They are tuned to different tasks for polishing different materials.

  • Different grain structures
  • Acid and basic reactive suspensions in the pH range from 3.5 to 10
  • Grain size distributions of 0.2 µm to 0.050 µm (200 - 50 nm)
  • A unique system to prevent the crystallization
  • Water-free suspensions

Silica - suspensions were originally developed for the polishing of silicon wafers. The mode of operation of this silica-suspension is chemically-mechanically. The sample surface will be etched; the resulting coating is removed with the soft silica, leaving the surface almost free of deformation. Just as in wafer polishing, this is best achieved when the suspension is added just before use an oxidizing agent. Often you use hydrogen peroxide or acids / bases in combination with a salt. You take an etching agent which is often used simultaneously with the etching of the finished object. The oxidation- or etching agent must be added just before use, because it can trigger changes in the silica-suspension such flocculation or coagulation.

 

Crystallization

One problem of the Silica-suspensions is the crystal precipitation after the application. If the liquid of the suspension evaporated after the final preparation, the Silica-content concentrates. Thus there is a precipitation of crystals that cannot be resolved by the addition of a new suspension. The crystals are embedded in the polishing cloth, which can no longer be used.

We have developed a very effective method to stop the crystal precipitation. This method reduces the water evaporation, and with our Colloidal silica it is other than before possible to dissolve the precipitated crystals once again. Thus extends the lifetime of the polishing cloth!

 

Overview Final Polishing suspensions

Description

Grain size

pH-
 value
Concentration
gr/l

Colloid

0,05

10

585

Fumed, alkaline

0,12

10

238

Fumed, alkaline

0,2

10

238

Fumed, water-free

0,2

-

240

 

 

 

 

 

 

 

                                                          

 

Water-free Silica-Final polishing suspensions

We offer a water-free version of our silica suspension. We use ethanol instead of the water. Because the polishing takes place in a water-free area, the mode of operation of this silica suspension is chemically-mechanically as with other silica suspensions. Etching and oxidation does not occur. Therefore, the effect of this suspension is purely mechanical. Particularly suitable for final polishing of water-sensitive materials are for example magnesium and zinc layers.

Grain size: 0.2 µm
Concentration: 238 g / l
Package size: 1 liter and 5 liter

We also offer:

Colloidal Silica-Final polishing suspension 0.05 µm (50 nm) basic
Silica-Final polishing suspension 0.2 µm (200 nm) basic
Silica-Final polishing suspension 0.12 µm (120 nm) basic
Package size: 1 liter and 5 liter
 
We also provide Aluminum oxide polishing suspensions, pH-value: neutral, grain sizes
1 µm, 0,7 µm und 0,25 µm.