Variations in Composition and Physical Properties

This contradiction in results almost certainly depends on differences in the chemical composition, hardness, and particle size of different sources of the same generic type of by-product abrasive. 

By-product abrasives are usually considered one-time abrasives, although there are indications that at least some of them may be recyclable. In the repainting of the Alvsboig bridge, Bjoigum found that, after one use, 80% of the particles were still larger than 250 pm and concluded that the abrasive could be used between three and live times [4], 

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