Investigation of effects of diesurface angle, temperature and blank holderforce on the hardness distribution forming in material after deepdrawing process

Abstract

In this study, it is aimed to determine the effects of die surface angle, temperature and blank holder force on the hardness of the obtained cups by deep drawing method. In the study, 4 different die surface angles (0°, 5°, 10°, 15°), four different temperatures (25^oC, 100^oC, 175^oC, 250^oC) and three different blank holder force (1200 N, 2400 N, 3600 N) were used.  As a result of the studies, it was determined that the hardness of the cups decreased with the increase of the temperature, the hardness of the cups increased with the increase of the blank holder force and the most ideal die surface angle is 5-10° in terms of both hardness and forming. Moreover, it has been observed that the lowest hardness in the obtained cups is at the bottom of the cup and the hardness increases as moved towards the mouth of the cup. When the limit drawing ratio increased from 2.14 to 2.75, there was no increase in hardness due to the effect of temperature. As a result, it is clearly seen that the determined parameters play an important role in controlling the hardness during deformation.

Keywords

• Deep drawing,hardness distribution,die surface angle,limit drawing ration

Derin çekme işlemi sonrası malzemede oluşan sertlik dağılımı üzerine kalıp yüzey açısı, sıcaklık ve baskı plakası kuvveti etkilerinin incelenmesi

Abstract

Bu çalışmada, derin çekme yöntemi ile elde edilen kapların sertliğine kalıp yüzey açısı, sıcaklık ve baskı plakası kuvvetinin etkilerinin belirlenmesi amaçlanmıştır. Çalışmada, 4 farklı kalıp yüzey açısı (0°, 5°, 10°, 15° ), 4 farklı sıcaklık(25°C, 100^oC, 175^oC, 250^oC) ve 3 farklı baskı plakası kuvveti (1200 N, 2400 N, 3600 N) kullanılmıştır. Yapılan deneyler sonucunda sıcaklığın artmasıyla kapların sertliğinin düştüğü, baskı plakası kuvvetinin artması ile kapların sertliğinin çok az arttığı ve hem sertlik hem de şekillendirme açısından en ideal kalıp açısının 5-10° olduğu belirlenmiştir. Ayrıca elde edilen kaplardaki en düşük sertliğin kap tabanında olduğu, kap ağzına doğru çıkıldıkça sertliğin arttığı görülmüştür. Limit çekme oranı 2,14'den 2,75'e çıktığında sıcaklığın etkisi ile sertlikte artış olmamıştır. Sonuç olarak, belirlenen parametrelerin deformasyon sırasında oluşan sertliğin kontrolünde önemli rol oynadığı net bir şekilde görülmüştür.

Keywords

• Derin çekme,sertlik dağılımı,kalıp yüzey açısı,limit çekme oranı

References

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