SPOT WELDABILITY OF DUAL-PHASE STEEL

The spot welding characteristics of VAN-QN (80), a dual-phase HSLA (high strength, low alloy) steel, were examined with regard to the strength and ductility of spot welds under static, impact and cyclic loading and compared to a conventional V-N HSLA steel and SAE (Society of Automotive Engineers) 1008 low carbon steel. The maximum tensile shear strength of VAN-QN (80) spot welds was found to be proportional to the thickness and ultimate tensile strength of the base metal. VAN-QN (80) spot welds, therefore, were only slightly lower in strength than those in a conventional 80 ksi yield strength HSLA steel but up to twice the strength of welds in low carbon steel. Weld ductility was lower for VAN-QN (80) than for low carbon steel but greater than for conventional HSLA steel and increased with material thickness. The impact and fatigue properties of VAN-QN (80) welds were similar to those in conventional HSLA and low carbon steels. Weldability, as determined by the range of current over which acceptable welds could be produced, decreased with increasing thickness and was the same for VAN-QN (80) as for low carbon steel. The excellent weldability of VAN-QN (80) steel is attributed to a combination of the following properties: moderate hardenability, insensitivity of the dual-phase microstructure to softening by the heat inputs typical of spot welding, and a low yield strength to ultimate tensile strength ratio.

• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/issn/01487191
• Supplemental Notes:
  • Presented at SAE Congress and Exposition, Detroit, 26 February-2 March 1979.
• Corporate Authors:

  Society of Automotive Engineers (SAE)

  400 Commonwealth Drive
  Warrendale, PA  United States  15096
• Authors:
  • Pollard, B
  • Goodenow, R H
• Publication Date: 1979

Media Info

• Features: References;
• Pagination: 16 p.
• Serial:
  • SAE Technical Paper
  • Publisher: Society of Automotive Engineers (SAE)
  • ISSN: 0148-7191
  • EISSN: 2688-3627
  • Serial URL: http://papers.sae.org/

Subject/Index Terms

• TRT Terms: Dual phase steel; Ductility; Fatigue strength; High strength steel; Low alloy steel; Repeated loads; Shear strength; Shock resistance; Spot welding; Tensile strength; Thickness; Welding; Yield strength
• Uncontrolled Terms: Impact strength; Weldability
• Subject Areas: Safety and Human Factors;

Filing Info

• Accession Number: 00394083
• Record Type: Publication
• Source Agency: National Highway Traffic Safety Administration
• Report/Paper Numbers: SAE 790006, HS-026 872U
• Files: HSL, USDOT
• Created Date: May 31 1985 12:00AM