With the presentation of a theory of liquid alloys, we have now assembled all the necessary tools for the ab initio construction of an alloy phase diagram.

Alloy Phase Diagrams

Spot welding, particularly resistance spot welding (RSW), is a critical joining process in automotive industry. The development of advanced high strength steels for applications in automotive industry is accompanied with a challenge to better understand the physical and mechanical metallurgy of these materials during RSW. The present paper critically reviews the fundamental understanding of structure–properties relationship in automotive steels resistance spot welds. The focus is on the metallurgical characteristics, hardness–microstructure correlation, interfacial to pullout failure mode transition and mechanical performance of steel resistance spot welds under quasi-static, fatigue and impact loading conditions. A brief review of friction stir spot welding, as an alternative to RSW, is also included.

Critical review of automotive steels spot welding: process, structure and properties

Understanding effects of welding on strength and formability is critical to support wider application of advanced high strength steels in automotive components In this study, High Strength Low Alloy (HSLA) and DP980 (Dual Phase, 980 MPa) sheet steels were welded with a 4k Wdiode laser Mechanical properties of welds and parent metals were assessed by tensile and limiting dome height tests, and related to microhardness distribution across the welds The formability of HSLA welds was insensitive to the welding process and comparable to that of parent metal For the DP steel, weld formability was much lower than that of corresponding parent metal, which appeared to be due to the formation of soft zones in the outer region of the Heat affected zone (HAZ) of the welds It was found that increase of welding speed resulted in a slight increase of formability of the DP steel, associated with a reduction in the microhardness difference between base metal and HAZ soft zones DOI: 101115/12744417

https://uwaterloo.ca/centre-advanced-materials-joining/sites/ca.centre-advanced-materials-joining/files/uploads/files/asme-jemt-2007_xia.pdf

A Comparative Study of Formability of Diode Laser Welds in DP980 and HSLA Steels

Liquid Zn-assisted embrittlement during resistance spot welding of Zn-coated high strength steels induces risks of surface cracking. This paper presents a state-of-the-art review on the surface cra...

Liquid metal embrittlement during resistance spot welding of Zn-coated high-strength steels

Experimental and modeling investigation of the failure resistance of Advanced High Strength Steels spot welds

Weld fracture was investigated in relation to weld parameters and steel sheet characteristics.

X. Q. Gayden

Papers

Development of requirements for resistance spot welding dual-phase (DP600) steels. Part 1: The causes of interfacial fracture