Accession Number:

ADA214290

Title:

Heat Treatment Investigation of 4330 Vanadium-Modified Steel

Descriptive Note:

Final rept.

Corporate Author:

ARMY LAB COMMAND WATERTOWN MA MATERIAL TECHNOLOGY LAB

Report Date:

1989-08-01

Pagination or Media Count:

17.0

Abstract:

The shear pin material for the T5106 155-mm torsional impact round was originally specified to have been 4340 steel. It was determined by the authors that the required properties of an ultimate shear strength of 150 ksi and Charpy impact value of 20 ft-lb at 40 F were not obtainable in 4340. The decision to employ 4330 vanadium-modified steel as a substitute shear pin material initiated this heat treatment and mechanical property investigation. The 4340 steel is a low alloy, martensitic, ultrahigh strength steel developed from the modification in composition of 4340 steel. The reduction of the carbon level in this alloy increases its performance, relative to its predecessor in the areas of fracture toughness, weldability, and general fabrication. Mechanical properties were determined from 12-in and 58-inch-diameter bar stock for austenitizing temperatures of 1500 and 1600 F and tempering temperatures ranging from 375 and 675 F. The material was evaluated for the specification requirements mentioned above in addition to being tested for hardness, fracture toughness, and tensile properties. jes

Subject Categories:

  • Metallurgy and Metallography

Distribution Statement:

APPROVED FOR PUBLIC RELEASE