Accession Number : AD0918121

Title :   Plasma-Arc Welding of Naval Structural Alloys.

Descriptive Note : Research and development rept.,

Corporate Author : DAVID W TAYLOR NAVAL SHIP RESEARCH AND DEVELOPMENT CENTER ANNAPOLIS MD

Personal Author(s) : McCaw, Robert L.

Report Date : APR 1974

Pagination or Media Count : 27

Abstract : The application of plasma-arc welding to the fabrication of advanced high performance ships materials, utilizing the key hole mode, has been investigated. Single-pass autogenous butt welds have been produced in 0.062- to 0.375-inch-thick HY-130 steel, 0.062- to 0.250- inch-thick 17-4 precipitation-hardened stainless steel, and 0.070- to 0.480-inch-thick titanium (6A1-4V). Radiographically sound welds with tensile joint efficiencies approaching 100% were produced in the aswelded condition for HY-130 steel and titanium (6A1-4V). Defects were found by radiography in one of the six 17-4 precipitation-hardened stainless steel welds, but satisfactory tensile properties were obtained in each case. It was determined that keyhole-mode welding parameters could be varied over a relatively wide range, while still producing a satisfactory weld bead for specific thicknesses of each material. The investigation revealed that auxiliary inert gas shielding was required on the weld surface for all three materials to prevent atmospheric contamination. Future work will include an investigation of plasma-pipe welding, evaluation of pulsed-plasma-arc welding, and development of one-sided welding techniques for plasma-arc welding of hull materials to internal framing or stiffening members. (Author)

Descriptors :   *ARC WELDING), (*STEEL, (*TITANIUM ALLOYS, ARC WELDING), (*STAINLESS STEEL, ARC WELDING), PLASMAS(PHYSICS), ARC WELDS, RADIOGRAPHY, DEFECTS(MATERIALS), TENSILE PROPERTIES, THICKNESS, INERT GAS WELDING, HEAT TREATMENT, MICROSTRUCTURE, HARDNESS, SHIELDING, SURFACE EFFECT SHIPS, HYDROFOIL CRAFT.

Subject Categories : Properties of Metals and Alloys
      Fabrication Metallurgy
      Marine Engineering

Distribution Statement : APPROVED FOR PUBLIC RELEASE