Prediction and Analysis of Cutting Forces Including the Effect of Tool Runout During End Milling

Abstract

In this study, a cutting force model is presented, which includes the effects of tool runout to predict cutting forces in end milling. In the model, the end mill is separated into a series of disc elements along its axis to reflect the effect of the helix angle. The cutting forces are predicted at each time interval with a mechanistic model in which the force coefficients are defined as the exponential functions of the average chip thickness. The effect of tool runout on chip load is considered based on the true path of the flutes. An in-depth analysis indicates that tool runout shifts the cutting force pattern from the tooth passing frequency to the spindle rotational one. This model is also validated with the comparison of experimental cutting forces available in the literature with those from simulation for aluminum alloy Al7075-T6, and provides a satisfactory prediction of cutting forces.

Keywords

• Cutting force
• mechanistic model
• end milling
• tool runout

Parmak Frezeleme Sırasında Takım Salgısının Etkisi Dahil Edilerek Kesme Kuvvetlerinin Tahmini ve Analizi

Abstract

Bu çalışmada, parmak frezelemede kesme kuvvetlerini tahmin etmek için takım salgısının etkilerini içeren bir kesme kuvveti modeli sunulmuştur. Modelde, parmak freze helis açısının etkisini yansıtmak için ekseni boyunca bir dizi disk elemana ayrılmıştır. Kesme kuvvetleri, kuvvet katsayılarının ortalama talaş kalınlığının üstel fonksiyonları olarak tanımlandığı mekanistik model ile her bir zaman aralığında tahmin edilmiştir. Takım salgısının talaş yükü üzerindeki etkisi kesici kenarların gerçek yolu esas alınarak incelenmiştir. Ayrıntılı bir analiz, takım salgısının kesme kuvveti desenini diş geçiş frekansından iş mili dönme frekansına değiştirdiğini göstermektedir. Bu model, Al7075-T6 alüminyum alaşımı için literatürde bulunan deneysel kesme kuvvetlerinin benzetimden elde edilenlerle karşılaştırılmasıyla da doğrulanmış ve kesme kuvvetlerinin tatmin edici bir tahmini sağlamaktadır.

Keywords

• Kesme kuvveti
• mekanistik model
• parmak frezeleme
• takım salgısı

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