Blanking is a widely used process in sheet metal forming industry. In blanking process, clearance is a major parameter which directly effects outcomes such as surface quality of the blanks and cutting load. An unadjusted clearance value has a high potential to lead poor surface quality or more energy consumption as a result of becoming too loose or too tight. The main aim in blanking process is to achieve both good surface quality and lowest cutting load at the same time. Lower cutting forces at higher clearances can be considered suitable in terms of energy consumption but on the other hand the surface quality degrades gradually. These two parameters should be in conjunction with each other. So, the effect of clearance on the surface quality should be investigated for the material to be used. In this study, investigations were made experimentally to observe the effect of clearance on the surface quality of S235JR (St 37-2) and AISI 316 steel. Both steels with 2 mm thickness were blanked by using a 300 kN hydraulic press under seven different clearance values (2%, 4%, 6%, 8%, 12%, 14% and 16% of thickness) for experimental studies. The change in surface quality (distribution of zones) and cutting loads were given in the scope of the work. The best clearance was considered 4% for S235JR structural steel and 6% for AISI 316 stainless steel.
Anahtar Kelimeler: Clearance, Surface quality, Punch load, Blanking.
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