Grain size is an important factor in determining the cooling rate of a melt. The faster the cooling, the smaller the grain size.
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Introduction
Grain size is an important factor in the properties of a material, and can be influenced by the cooling rate of the melt. In general, faster cooling rates will result in smaller grain sizes, and slower cooling rates will result in larger grain sizes.
Grain Size
Grain size generally indicates the cooling rate of a melt. So, for example, a rock with large crystals would have cooled slowly, while a rock with small crystals would have cooled quickly.
What Does Grain Size Generally Indicate About the Cooling of a Melt?
Grain size generally indicates the cooling rate of a melt. A slower cooling rate will result in larger grain sizes, while a faster cooling rate will result in smaller grain sizes.
Rapid Cooling
Grain size generally indicates the rate of cooling of a melt. A large grain size generally indicates rapid cooling, while a small grain size generally indicates slow cooling.
Slow Cooling
The rate of cooling generally has the greatest influence on grain size. Slow cooling rate leads to large grains, while fast cooling rates lead to smaller grains. The difference in cooling rate is accomplishes by varying the thickness of the sample, using different media for cooling (liquid vs. air), or by rapidly quenching the sample in a cold liquid.
Conclusion
Grain size generally indicates the cooling rate of a melt. A slow cooling rate results in large grains, while a fast cooling rate results in small grains.