Accession Number : ADA954402

Title :   The Application of Colmonoy Number 1 and Dymonhard Number 65 by the Surface Hardening of Armor Plate,

Corporate Author : WATERTOWN ARSENAL MA

Personal Author(s) : Reed,E. L. ; Matthews,N. A.

Report Date : 30 OCT 1941

Pagination or Media Count : 41

Abstract : Colmonoy No.1 and Dymonhard No.65 are not recommended for surface hardening of cast or rolled armor since: (1) Both of these materials contain relatively high alloy context some of which are classed as strategc; (2) The resulting hard surfaces are either porous or contain many incipient cracks. (3) The ballistic properties of the surface hardened plates were not sufficiently promising to warrant further investigation; (4) Both materials are difficult to apply to armor--The application of Colmonoy to 1/4-in and 3/8-in, thick rolled homogeneous armor drew the temper to such a degree that it was necessary to reheat these plates; (5) Both materials when applied to lighter gauges caused some warping of the plate; Although the price of Colomonoy per pound compares favorably with that of stainless steel electrodes, Dymonhard is further undesirable from the cost standpoint (nearly $3.00 per pound). The application of Dymonhard to the surface hardening of stainless ateel welds or armor has not proven successful.

Descriptors :   ALLOYS, ARMOR, ARMOR PLATE, BALLISTICS, CRACKS, ELECTRODES, HARDENING, HARDNESS, HOMOGENEITY, PLATES, ROLLING(METALLURGY), STAINLESS STEEL, SURFACES, THICKNESS, WELDS

Subject Categories : Metallurgy and Metallography
      Ballistics

Distribution Statement : APPROVED FOR PUBLIC RELEASE