Evaluation of drilling Al/B4C composites with carbide drills

In this study, cutting forces and torque was evaluated through Taguchi Method (TM) in the drilling of the high density B4C particle reinforced composites, which were produced through powder metallurgy-hot pressing method, with coated and uncoated carbide drills. Cutting speed (18, 25 and 35 m/min), feed rate (0.08, 0.112 and 0.16 mm/rev), coating properties (coated and uncoated) and the amounts of particle reinforcement (5%, 10% and 15% B4C) were used as the control factors. It was observed that the increased feed rate and particle reinforcement increased the axial force and torque, and decreased the cutting speed. The uncoated drills had a better performance than the coated drills. The amount of B4C reinforcement was observed to be the most effective parameter on the axial force and torque with the contribution ratios of 96.6% and 49.1%, respectively. Moreover, the correlation coefficients (R2) of the first order predictive equations developed for the axial force and torque were calculated as 0.895 and 0.854, respectively.

Al/B4C kompozitlerin karbür matkaplarla delinmesinin deðerlendirilmesi

Bu çalýþmada, toz metalurjisi-sýcak presleme yöntemiyle üretilen yüksek yoðunluklu B4C parçacýk takviyeli kompozitlerin kaplamalý ve kaplamasýz karbür matkaplarla delinmesinde kesme kuvvetleri ve tork deðerleri Taguchi metodu (TM) yardýmýyla optimize edilmiþtir. Kontrol faktörleri olarak kesme hýzý (18, 25 ve 35 m/dk), ilerleme miktarý (0.08, 0.112 ve 0.16 mm/dev), kaplama özellikleri (kaplamalý ve kaplamasýz) ve parçacýk takviye miktarý (%5, %10 ve %15 B4C) kullanýlmýþtýr. Artan ilerleme miktarý ve parçacýk takviyesinin eksenel kuvvet ve torku arttýrdýðý, kesme hýzýný ise düþürdüðü görülmüþtür. Kaplamasýz matkaplar, kaplamalý matkaplara kýyasla daha iyi performans sergilemiþtir. B4C takviye miktarýnýn sýrasýyla %96.6 ve %49.1 katký oranlarý ile eksenel kuvvet ve tork üzerinde en etkili parametre olduðu görülmüþtür. Ayrýca, eksenel kuvvet ve tork için geliþtirilen birinci dereceden tahmini denklemlerin korelasyon katsayýlarý (R2) sýrasýyla 0.895 ve 0.854 olarak hesaplanmýþtýr.