| ||Format||Pages||Price|| |
|PDF (264K)||10||$25||  ADD TO CART|
|Complete Source PDF (4.6M)||162||$64||  ADD TO CART|
The same properties that make engineering materials attractive for use on severe thermal and mechanical environments (e.g., high hardness, high temperature strength, high fracture toughness) generally tend to make those materials difficult to grind and finish. In the mid-1990's, a belt abrasion test was developed under subcontract to Oak Ridge National Laboratory to help to assess the grindability of structural ceramic materials. The procedure involves applying a 10 N normal force to the end face of a 3 × 4 mm cross-section test bar for 30 seconds which is rubbed against a wet, 220 grit diamond belt moving at 10 m/s. By measuring the change in the bar length after at least six 30-second tests, a belt grindability index is computed and expressed using the same units as a traditional wear factor (i.e., mm3/N-m). The test has shown an excellent capability to discriminate not only between ceramics of different basic compositions, e.g. Al2O3, SiC, and Si3N4, but also between different lots of the same basic ceramic. Test-to-test variability decreases if the belt is worn in on the material of interest. The surface roughness of the abraded ends of the test specimens does not correlate directly with the belt grindability index, but instead reflects another attribute of grindability; namely, the ability of a material to abrade smoothly without leaving excessive rough and pitted areas.
abrasion, abrasive wear, abrasive belts, ceramics, grinding, wear of ceramics
Senior research engineer, Oak Ridge National Laboratory, Oak Ridge, TN
Engineer, Caterpillar Inc., Peoria, IL