A NOVEL DESIGN TO MINIMIZE SPRINBACK, WRINKLING AND THICKNESS REDUCTION PROBLEM IN SHEET METAL FORMING PROCESS USING PROBABILISTIC APPROACH

Öz

In the sheet metal process, springback, wrinkling and thickness reduction have become one of the most common problems. In this study, three approaches are proposed to minimize springback, wrinkling and thickness reduction for automobile side panel, In the first approach, the effect of using double binder on springback, wrinkling and thickness reduction is studied, In the second approach, the use of optimization method in further improving formability of the automobile panel is investigated, With the optimization method, the most appropriate values of forming process parameters are calculated for optimum formability characteristics, Positions of the upper die and draw-bead, draw-bead radius, forces applied on the upper die surface and double binder surfaces are considered as process parameters, In finding optimum values, Finite Element Analysis, Response Surface Methodology and Genetic Algorithm are integrated, To achieve efficient and effective integration, a computer program is written, From this study it is observed that double binder with an appropriate stamping force improves formability significantly, Application of optimization method also improves further formability characteristics of the automobile panel, In the third approach probabilistic design method Monte Carlo Simulation are integrated to create an automated design tool, The reliability of the results are checked and refined by using probabilistic design techniques

Anahtar Kelimeler

• Sheet Metal Forming,Optimization Techniques,Finite Element Analysis,Monte Carlo Simulation

OLASILIK TABANLI YAKLAŞIM KULLANARAK METAL ŞEKİLLENDİRME İŞLEMİNDE GERİ YAYLANMA, BURUŞMA VE İNCELME PROBLEMİNİ EN AZA İNDİRECEK YENİ BİR TASARIM METODOLOJİSİ

Öz

Saç metal prosesinde, geri yaylanma, buruşma ve kalınlık azalması en yaygın sorunlardan biri haline gelmiştir. Bu çalışmada, otomobil yan panelinde geri yaylanma, buruşma ve kalınlık azalmasını en aza indirmek için üç yaklaşım önerilmiştir. İlk yaklaşımda, çift pot çemberi kullanılmasının geri yaylanma, buruşma ve kalınlık azaltma üzerindeki etkisi incelenmiştir. İkinci yaklaşımda, otomobil panelinin şekillendirilebilirliğinin daha da iyileştirilmesinde optimizasyon yönteminin kullanımı incelenmiştir. Optimizasyon yöntemiyle, en uygun şekillendirme özellikleri için şekillendirme işlemi parametrelerinin en uygun değerleri hesaplanmıştır. Optimum değerleri bulmada Sonlu Elemanlar Analizi, Tepki Yüzey Metodolojisi ve Genetik Algoritma birleştirilmiştir. Etkili entegrasyon sağlamak için bir bilgisayar programı yazılmıştır. Bu çalışma çift pot çemberininin kullanımı biçimlendirilebilirliği önemli ölçüde arttırdığı gözlenmiştir. Üçüncü yaklaşımda olasılıksal tasarım yöntemi Monte Carlo Simülasyonu, otomatik bir tasarım aracı oluşturmak için entegre edilmiştir, Sonuçların güvenilirliği, olasılıksal tasarım teknikleri kullanılarak kontrol edilmiş ve iyileştirilmiştir.

Anahtar Kelimeler

• Metal Şekillendirme,Optimizasyon Teknikleri,Sonlu Elemanlar Analizi,Monte Carlo Simülasyonu

Kaynakça

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