Accession Number:
AD0272162
Title:
MATERIALS - SAE 4340 STEEL CHROME DIFFUSION PROCESSED - PROPERTIES OF
Descriptive Note:
Corporate Author:
GENERAL DYNAMICS/FORT WORTH TEX
Personal Author(s):
Report Date:
1962-01-16
Pagination or Media Count:
1.0
Abstract:
The mechanical properties of SAE 4340 steel having a diffused Cr surface treatment were evaluated. A comparison of properties was obtained for the steel with the diffused Cr case, a Cr plated surface, and bare. Two heat treat conditions, 200 to 220 and 260 to 280 ksi, were investigated. Neither the Cr diffusion nor the Cr plating treatments affected the tensile or bend properties of the steel. The chrome diffusion treatment rendered the SAE 4340 steel extremely notch sensitive in the 260 to 280 ksi heat treat condition. Both surface treatments lowered the fatigue strength of the steel at room temperature and 350 F. The Cr diffused specimens gave slightly better rotating beam fatigue results than the plated specimens in the 260 to 280 heat treat condition. The wear resistance of the steel was improved by both surface treatments. Author