Heat Treatment Investigation of 4330 Vanadium-Modified Steel
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 1/2-in and 5/8-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)
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 01, 1989
- Accession Number
- ADA214290
Entities
People
- Charles F. Hickey Jr.
- David W. Dix
- Mary E. O'donovan