Niğde Ömer Halisdemir Üniversitesi Mühendislik Bilimleri Dergisi

Yazarlar: Bora ŞENER

Konular:Mühendislik, Makine

DOI:10.28948/ngumuh.826850

Anahtar Kelimeler:Yld2000,Sequential quadratic programming,Active-set method,Planar anisotropy,Yield surfaces

Özet: In this study, performances of sequential quadratic programming and active-set methods from numerical optimization techniques were investigated in the determination of Yld2000 yield function coefficients. Two aluminum alloys (AA6111-T4, AA6181-T4) and a high strength steel sheet material (DP980) were selected in the study. Methods were examined according to their convergence rate and the number of function evaluations that occurred during the minimization and it was determined that active-set method was more successful than sequential quadratic programming for three materials. The variations of the yield stress ratios and Lankford coefficients in the sheet plane and positive regions of yield surfaces of the materials were predicted and theoretical results were compared with experimental results to validate the method. It is seen from the comparisons that planar anisotropy and yield surfaces of the materials in the positive regions could be successfully predicted.

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