Accession Number:

ADA394411

Title:

Characterization of the Microstructure of 50% Nickel - 50% Chromium Alloy Produced by Spray Metal Forming

Descriptive Note:

Technical rept.

Corporate Author:

NAVAL SURFACE WARFARE CENTER CARDEROCK DIV BETHESDA MD SURVIVABILITY STRUCTURES AND MATERIALS DIRECTORATE

Report Date:

2001-04-01

Pagination or Media Count:

29.0

Abstract:

In order to understand the microstructure of 50V0 nickel - 50 chromium alloy produced using spray forming, 3 mm diameter disks of the alloy were cut from several samples. The disks were thinned by electrochemical jet polishing using a mixture of HJP04 and H2S04. The microstructure is very complex. Some areas showed a composite structure of spherical 5- Cr-Ni particles imbedded in a dimpled matrix of Cr-Ni. Some areas had a distribution of spherical 8- Cr-Ni and Cr-Ni imbedded in planar nickel matrix. The most interesting result is that the microstructure consisted of areas of fine disc shaped Ni3C, Cr2C and CrC carbide precipitates dispersed in a nickel matrix. These carbides always tend to orient in a preferred direction, and formed a concentric ring type structure.

Subject Categories:

  • Laminates and Composite Materials
  • Properties of Metals and Alloys

Distribution Statement:

APPROVED FOR PUBLIC RELEASE