Accession Number : AD0707400

Title :   METALLOGRAPHIC TECHNIQUE FOR THE DEVELOPMENT OF MICROSTRUCTURAL CONSTITUENTS IN GUN STEEL.

Descriptive Note : Technical rept.,

Corporate Author : WATERVLIET ARSENAL N Y

Personal Author(s) : Brassard,Theresa V. ; Nolan,Charles J.

Report Date : MAY 1970

Pagination or Media Count : 19

Abstract : An investigation was undertaken to develop etching procedures to clearly distinguish certain metallographic features of large forgings. The investigation demonstrates that (1) good microstructure resolution was obtained in untempered martensite using a 2% nital etchant, (2) either 25% sodium bisulfite in water or 4% picral plus hydrochloric acid yielded the best results for both tempered martensite and a duplex structure of tempered martensite and tempered lower bainite, and (3) an aqueous solution of 1% picric acid and 7% sodium tridecylbenzene sulfonate proved highly satisfactory in revealing both the prior austenitic grain boundaries and the macrostructure. (Author)

Descriptors :   (*STEEL, MICROSTRUCTURE), ETCHING, GRAIN BOUNDARIES, GUN BARRELS, METALLOGRAPHY

Subject Categories : Properties of Metals and Alloys

Distribution Statement : APPROVED FOR PUBLIC RELEASE