Hava etkili baskı plakasının derin çekme işlemlerine etkisinin deneysel olarak incelenmesi

Derin çekme işlemi ile düz sac levhadan farklı geometrilerde özdeş ve dikişsiz kaplar üretilmektedir. Sac levha derin çekme esnasında zımbanın etkisiyle kalıp boşluğuna akarken buruşmaya ve kopmaya zorlanır. Buruşmaya zorlanan sac levha kalınlaşır ve baskı plakası ile kalıp arasında sürtünmenin artmasına sebep olur. Buruşmaları ve kopmaları engellemek ve daha derin kaplar çekebilmek için çeşitli tiplerde baskı plakaları kullanılmaktadır. Sanayide ve deneysel çalışmaların çoğunda kalıp boşluğuna metal akışını kontrol etmek için hassas yüzey işlemlerine tabi tutulmuş “Düz Yüzeyli Baskı Plakaları (DYBP)” kullanılmaktadır. Bu işlemlerde sürtünmenin azaltılması için kalıp-sac levha-baskı plakası ara yüzeylerinde yağlama işlemi de yapılmaktadır. Yapılan bu çalışmada, deneylerde kullanılmak üzere hava etkili baskı plakası (HEBP) tasarlanmış ve imal edilmiştir. Yeni geliştirilen bu hava etkili baskı plakasının derin çekmeye etkileri deneysel olarak incelenmiş ve düz yüzeyli baskı plakası ile kıyaslanmıştır. 1 mm kalınlığındaki Al-1050 alaşımlı alüminyum malzemeden silindirik kapların derin çekilmesinde, HEBP kullanılarak DYBP’ na nazaran daha derin kapların çekilebildiği tespit edilmiştir.

Experimental investigation of influence air effected blank holder in deep drawing processes

With the deep drawing process, identical and seamless cups have been produced from flat sheet metal. Sheet metal has been forced to wrinkle and fracture while flowing to die cavity. During this time it becomes thicker and this causes to increase friction between die surface and blank holder. Various types blank holders have been used to prevent wrinkling and fracture and to obtain deeper cups. In industry and experimental studies, flat surfaced blank holders (FSBH) having a smooth surface have been used to control metal flow to the die cavity. Lubrication has been made among die-sheet metal and blank holder to reduce friction in deep drawing processes. In this study, air effected blank holder (AEBH) has been designed and manufactured to use in experiments. Effect of newly developed blank holder on deep drawing process has been investigated experimentally and compared with flat surfaced blank holder. With the use of AEBH and 1 mm thickness of Al-1050 aluminum alloy blanks, deeper cups have been obtained when compared with FSBH in deep drawing of cylindrical cups.

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