Accession Number : ADA954156

Title :   Armor: Temper Brittleness in Cast and Rolled Armor Plate.

Descriptive Note : Experimental rept.,

Corporate Author : WATERTOWN ARSENAL LABS MA

Personal Author(s) : Reed,E. L.

Report Date : 27 DEC 1943

Pagination or Media Count : 43

Abstract : The objective of this experiment was to determine if the present low alloy cast and rolled armor is subject to temper brittleness as a result of slow cooling from the final draw temperature. The results of this investigation indicated that cast and rolled low alloy armor slowly cooled from the draw temperature were more susceptible to temper brittleness (as measured by the V-notch Charpy test) than the same material quickly cooled from the draw. The embrittling effect noted in the ballistic tests of some of the rolled armor plates which were slowly cooled from the draw may have been due to the fact that these rolled plates were subjected to a more severe ballistic test as compared to the cast plates which were also slowly cooled from the draw. In general and in contrast to some fairly well accepted beliefs, in the steel studied, molybdenum does not seem to be effective in eliminating, or reducing temper brittleness in material slowly cooled from the draw temperature. The relatively low Charpy impact values obtained at subzero temperatures were related to the heterogeneous microstructures resulting from inadequate hardening of the steel during the quench.

Descriptors :   *COLD ROLLED PROCESS, *ARMOR PLATE, *BRITTLENESS, ARMOR, BALLISTICS, CASTINGS, CHARPY IMPACT TESTS, EMBRITTLEMENT, HARDENING, HETEROGENEITY, HIGH RATE, INTENSITY, MICROSTRUCTURE, MOLYBDENUM, PLATES, STEEL, TEST METHODS, VALUE

Subject Categories : Fabrication Metallurgy
      Ballistics

Distribution Statement : APPROVED FOR PUBLIC RELEASE