Crack Arrest Toughness of 4140, 1340 and 4340 Steel
Abstract
In an earlier study, the crack arrest fracture toughness of 4140 and 4340 steel was measured as a function of yield strength and test temperature. The yield strength was varied over the range of 140 to 180 ksi, and the temperature from -65 to +165F, the ranges of most interest for armament materials. Both materials were evaluated with full-thick specimens using one- inch thick plates. In this thickness, 4340 through hardens, while 4140 does not, so that the toughness difference reported for these two materials was a result of both composition and microstructure differences. The present study was undertaken to add 1340 steel to the comparison. However, to avoid having mixed microstructures, the 1340 and two new heats of 4140 steel were heat treated in thinner sections so that they would be martensitic through their thickness.
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 01, 1981
- Accession Number
- ADA129837
Entities
People
- E. J. Ripling
- P. B. Crosley
Organizations
- Materials Research Laboratory