Accession Number : AD0489402

Title :   DYNAMIC PRESSURE HARDENING OF IRREGULAR SHAPES.

Descriptive Note : Summary technical rept. 23 Jun 64-22 Mar 66,

Corporate Author : AEROJET-GENERAL CORP DOWNEY CA

Personal Author(s) : Doherty, A. E. ; Mykkanen, J. ; Henriksen, E. K.

Report Date : JUL 1966

Pagination or Media Count : 110

Abstract : The strengthening and hardening effects of shock waves in metal alloys were investigated, and an explosive hardening production technique was developed. Specimens of AISI 1018, AISI 4335, AISI 4340, and AISI H-11 steels; 18% nickel maraging steel; AISI 301, AISI 303, AISI 304, AISI 410, and AISI 416 stainless steels; and 6061 aluminum were shocked by detonation of Detasheet A, Aerex L-1, nitroguanidine, and C-4 explosives in direct contact with the specimen surface. All materials tested showed an initial hardness increase in various degree, with the greatest increase occurring in metals with the highest content of free ferrite and the lowest content of pearlite. The maximum initial hardness increase observed was 25 R sub B in AISI 301 stainless steel. Far greater gains in strength and hardness were obtained by the application of a combined shocking and heat treatment to specimens of AISI 4340, AISI H-11, and 18% nickel maraging steels. These specimens showed tensile properties ranging from 29,000 psi to approximately 70,000 psi higher than had been obtained with conventional heat treatments, and with little or no decrease in ductility.

Descriptors :   (*SHOCK WAVES, ALLOYS), (*ALLOYS, HARDENING), EXPLOSIVES, STEEL, STAINLESS STEEL, MARAGING STEELS, ALUMINUM, NITROGUANIDINE, HARDNESS, STRENGTH(PHYSIOLOGY), SPALLATION, FRACTURE(MECHANICS), MICROSTRUCTURE, MECHANICAL PROPERTIES, PETN, PRESSURE.

Subject Categories : Properties of Metals and Alloys
      Fabrication Metallurgy
      Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE