Accession Number : ADA113674

Title :   A Study of the Dependence of Microsegregation on Critical Solidification Parameters in Rapidly-Quenched Structures.

Descriptive Note : Annual technical rept. Aug 80-Sep 81,


Personal Author(s) : Snow,David B ; Greenwald,L E ; Breinan,Edward M

PDF Url : ADA113674

Report Date : Jan 1982

Pagination or Media Count : 55

Abstract : Grade AH32 structural hull steel clad with varying thicknesses of 317L stainless steel were bead-on-plate welded with a continuous, CO2 laser operated at power settings of from 2 to 9 kW and scanned at 5 to 76 cm/sec. The resulting fusion zone shapes and microstructures were examined by light microscopy and electron microprobe to determine the variation in welding efficiency and fusion zone segregation as a function of beam power input and cladding thickness. Due to the similarity in thermal conductivity and reflectivity of the cladding and substrate, the degree of the dilution of chromium and nickel in the fusion zone depended only on the relative volumes of cladding and substrate mixed in it, and not the absolute values of cladding thickness or fusion zone depth. Welding efficiency increased with power and beam traverse speed at constant fusion zone depth.

Descriptors :   *Steel, *Stainless steel, *Laser welding, Solidification, Quenching, Hulls(Structures), Microstructure, Quantitative analysis, Cladding, Thickness, Heat transfer, Thermal conductivity, Quick reaction, Electron probes, Fusion welding, Penetration, Substrates, Chromium alloys, Nickel alloys, Equations

Subject Categories : Properties of Metals and Alloys
      Fabrication Metallurgy

Distribution Statement : APPROVED FOR PUBLIC RELEASE