A Program for the Fatigue Analysis of Automotive Spot-Welds Based on Finite Element Calculations 962566

A Software system has been developed which permits fatigue life predictions to be made for automotive spot welds joining two steel sheets, based on finite-element analyses. The method requires the spot welds in a structure to be modelled as stiff bar elements in a relatively coarse mesh, with the bar elements acting as force transducers. The method uses the bar element cross sectional forces and moments to calculate the “structural stresses” in each spot-weld nugget and the adjacent sheets.
The system permits the user to play complex loading histories through a finite element model, using either a quasi-static or transient approach to stress history determination. The method provides a convenient way to predict the locations and lives of fatigue sensitive spot welds, and includes graphical tools to assist in interpretation of results. Studies so far indicate that in a typical application such as an automotive body structure, the system correctly identifies all the spot welds that are likely to give rise to durability problems. Using generic S-N curves, life predictions made so far have tended to be somewhat conservative. When S-N curves are used which are more representative of the material from which the component is constructed, more accurate life predictions can be made.


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


Members save up to 40% off list price.
Login to see discount.
Special Offer: With TechSelect, you decide what SAE Technical Papers you need, when you need them, and how much you want to pay.