Not sure what it is you are asking in your question. If the material you selected does not meet the minimum design metal temperature (MDMT), you typically need to select a more suitable material to meet this temperature. Impact testing is used to assure material compliance for a selected MDMT. Normalization is a heat treatment process that results in specific mechanical properties - typically slightly higher strength with lower elongation and reduced toughness over annealing or sub-critical annealing heat treatment.

Fine grain practice refers to materials that are cast and treated during solidification to produce a fine grain structure. Material is orginally ordered in this manner. Typically, fine grained steels have improved toughness and are used for low temperature applications.

If you can re-state your question, it might help to get the answer you need.