Accession Number:

AD0263972

Title:

SALT BATH HEAT TREATING PROCESSES

Descriptive Note:

Corporate Author:

WATERVLIET ARSENAL N Y

Personal Author(s):

Report Date:

1960-11-01

Pagination or Media Count:

1.0

Abstract:

The use of salt baths for quenching and solution treatment of steel was evaluated for the following steels 4340, 4140, 8640, 4330 modified, and 4130. Marquenched specimens of 14 to 1 in. in diameter indicate that 4340 and 4330 modified steels most successfully fulfilled requirements while other steels failed to produce a homogeneous martensite. The austempered specimens of all steels tested indicate unwanted transformation products are included with the bainitic structure desired. Investigations of the solution treatment of steel indicate that doubling the normal holding time produced a substantial increase in hardness of the 4130 steel while some increase was noted in 4140 and 8640 steels. Doubling the holding times for 4340 and 4330 modified steels resulted in negligible differences in hardness. This behavior may be partly due to Va in the latter to control grain size. Also, both steels contain Ni which sometimes does not form any complex carbide requiring longer solution times. Author

Subject Categories:

Distribution Statement:

APPROVED FOR PUBLIC RELEASE