EFFECTS OF COMPOSITION ON THE TRANSFORMATION CHARACTERISTICS AND TOUGHNESS OF WELD-HEATAFFECTED ZONES IN NI-CR-MO STEELS.

Abstract

As part of the program to define the composition limits within which an HY-130/150 steel would exhibit satisfactory weldability, the effects of carbon (0.05 to 0.21%), manganese (0.3 to 1.5%), phosphorus (0.003 to 0.027%), sulfur (0.003 to 0.027%), and nickel (1 to 9%) on the crack susceptibility, transformation characteristics, and toughness of the weld-heataffected zone were determined on 32 statistically selected NiCr-Mo steels. The results of the present study on the transformation characteristics of the weld-heat-affected zones of the Ni-Cr-Mo steels showed that changes in the martensite-start M sub s) temperature depended primarily on the carbon, manganese, and nickel contents; that the M sub s temperature varied inversely with the carbon, manganese, and nickel contents; and that the crack susceptibility of the weld-heataffected zones varied inversely with the M sub s temperatures. The results of the present toughness study showed that an increase in the sulfur content of Ni-Cr-Mo steels strongly decreased weld-heat-affected-zone toughness, particularly in the grain-coarsened region; that an increase in carbon moderately decreased toughness; and that an increase in the manganese and nickel slightly decreased toughness. The preceding observations were used extensively in selecting the carbon (0.10%), manganese (0.75%) , sulfur (less than 0.010%), and nickel (5.0 percent) contents of the 5Ni-Cr-Mo-V steel that is considered extremely promising as an HY-130/150 steel. (Author)

Document Details

Document Type
Technical Report
Publication Date
Apr 01, 1964
Accession Number
AD0600933

Entities

People

  • A. M. Rathbone
  • B. K. Stewart
  • L. P. Connor

Organizations

  • U.S. Steel

Tags

DTIC Thesaurus Topics

  • Elements
  • Manganese
  • Martensite
  • Observation
  • Phosphorus
  • Steel
  • Toughness
  • Weldability
  • Welds

Fields of Study

  • Materials science

Readers

  • Materials Science (Mechanical Engineering).
  • Metallurgy