Browse Publications Technical Papers 2013-01-1023
2013-04-08

Failure Mode and Fatigue Behavior of Friction Stir Spot Welds in Lap-Shear Specimens of Dissimilar Advanced High Strength Steels 2013-01-1023

Failure mode and fatigue behavior of friction stir spot welds made with convex and concave tools in lap-shear specimens of dissimilar high strength dual phase steel (DP780GA) and hot stamped boron steel (HSBS) sheets are investigated based on experiments and a kinked fatigue crack growth model. Lap-shear specimens with the welds were tested under both quasistatic and cyclic loading conditions. Optical micrographs indicate that under both quasi-static and cyclic loading conditions, the welds mainly fail from cracks growing through the upper DP780GA sheets where the tools were plunged in during the welding processes. Based on the observed failure mode, a kinked fatigue crack growth model is adopted to estimate fatigue lives of the welds. In the kinked crack fatigue crack growth model, the stress intensity factor solutions for fatigue life estimations are based on the closed-form solutions for idealized spot welds in lap-shear specimens. The fatigue life estimations are reasonably in agreement with the experimental results under low-cycle loading conditions but lower than the experimental results under high-cycle loading conditions.

SAE MOBILUS

Subscribers can view annotate, and download all of SAE's content. Learn More »

Access SAE MOBILUS »

Members save up to 18% off list price.
Login to see discount.
We also recommend:
JOURNAL ARTICLE

Failure Mode and Fatigue Behavior of Ultrasonic Spot Welds with Adhesive in Lap-Shear Specimens of Magnesium and Steel Sheets

2013-01-1020

View Details

TECHNICAL PAPER

Deep Drawing by Indirect Hot Stamping

2013-01-1172

View Details

JOURNAL ARTICLE

Failure Modes of Friction Stir Spot Welds in Lap-Shear Specimens of Dissimilar Advanced High Strength Steels under Quasi-Static and Cyclic Loading Conditions

2012-01-0479

View Details

X