Dicalcium silicate disintegration of air-cooled blast-furnace slag

1 Dicalcium silicate disintegration of air-cooled blast-furnace slag 

This test is used on crushed air-cooled blast-furnace slags to determine their susceptibility to disintegration resulting from the inversion of dicalcium silicate from the b form to the g form. This is sometimes called lime disintegration . 

According to CEN EN 1744-1 (2009), paragraph 19, the surface of crushed slag is fluoresced under the influence of ultraviolet light in the field of visible spectrum. The aspect and colour of fluorescence enable the detection of slags that are suspect to silicate disintegration. 

At the end of the test, observations made on the appearance of freshly broken surfaces are recorded. Slags that exhibit numerous or clustered large and small bright spots of a yellow, bronze or cinnamon colour on a violet background are recorded as suspect to disintegration. 

Slags with a uniform shine in various shades of violet and those exhibiting a limited number of bright spots uniformly distributed are deemed sound. 

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