Introduction of Sol-gel alumina abrasive grain
Sol-Gel Alumina abrasive is a new type abrasive grain totally different from traditional fused alumina. Sol-Gel is also called ceramic alumina grain,it is made by sol-gel process.
α-Al2O3 micro-crystal always added as seed into the raw mixed materials of Al2O3 H2O micropowder and water. By doing so,crystal will get more compact when calcined to get solid sol-gel grains. The calcining and sintering process are very important to make sol-gel crystal get small α-Al2O3 crystal size.
The features of sol-gel alumina abrasive grain:
1. Small crystal size about 100-500nm, which is even much smaller than zirconia alumina. And it’s hundredths of the size of normal fused alumina grains.So it will make abrasive wheels increase lifetime by several times than ordinary wheels.
2. Excellent self-sharpening performance. The sol-gel grain will get new grinding edges after grinding. The edges are get from the single grain crystal instead of off a whole crystal. That makes the grain much sharper than normal fused alumina.
3. The microscopic hardness of sol-gel alumina is about 1900-2400 kgs/cm2,which is higher than zirconia alumina. Thus,sol-gel alumina can make grinding and cutting easier for special hard metal such as Nickel chromium alloy and nickel titanium alloy.
4. The roughness is double of normal fused alumina,and even higher than zirconia alumina.
5. Low temperature grinding is another significant property of Sol-gel alumina abrasive grain. That will avoid much heat during grinding and cutting, so it won’t get hurt of workpiece surface.
6. Small size grinding edges and sharp grinding can avoid tiny crackle on workpiece.
Physical properties of Sol-gel alumina abrasive grain :
Product Name | SG Blue Ceramic Alumina Abrasive |
Method | Sol-Gel |
True Density | ≥3.90 g/cm³ |
Hv Hardness | 2100-2200(khf/mm³) |
Color | Blue |
Crystal size | 50-150nm |
Roughness | 65% |
Chemical composition of Sol-gel alumina abrasive grain
AL2O3 | 94-96% |
Y2O3 | 1-2% |
La2O3+NdO2 | 2-3% |
Applications of Sol-gel alumina abrasive grain:
Sol-gel alumina abrasive grain always mixed with other abrasive grains to make abrasive tools.
1. Diamond cutting wheel.
2. Diamond vitrified gear grinding wheel.
3. High level resin boned grinding wheel.
4. High level vitrified bonded grinding wheel.
5. Centerless grinding wheel.
6. High level cutting disc.
7. High level coated abrasives.
Specifications of Sol-gel alumina abrasive grain:
Grit designation | Mean diameter in um |
F16 | 1230 |
F20 | 1040 |
F22 | 885 |
F24 | 745 |
F30 | 625 |
F36 | 525 |
F40 | 438 |
F46 | 370 |
F54 | 310 |
F60 | 260 |
F70 | 218 |
F80 | 185 |
F90 | 154 |
F100 | 129 |
F120 | 109 |
F150 | 82 |
F180 | 69 |