Talaşlı imalat sırasında kesici takımda meydana gelen hasar mekanizmaları ve takım hasarını azaltma yöntemleri

Bu çalışmada takım ömrünü etkileyen takım hasar mekanizmaları incelenmiştir. Takım ömrü, işlenen parçanın kalitesini ve maliyetini direk olarak etkileyen bir faktördür. Takım ömrünü doğrulukla belirleyebilmek için, takım ömrünü olumsuz yönde etkileyen takım hasar mekanizmalarının bilinmesine gerek vardır. Herhangi bir kesici takım aşınma, plastik deformasyon veya kırılma yoluyla ömrünü tamamlar. Talaş kaldırma sırasında kesme kenarlarında, normal çalışma durumuna göre oldukça yüksek kesme hızlarında oluşan yüksek sıcaklıkla birlikte oldukça yüksek normal ve kayma gerilmeleri meydana gelir. Kesme şartlarına bağlı olarak kesme kenarlarında meydana gelen hasar mekanizmaları, karekteristikleri, önleme yöntemleri ve Tablo 2'de verilmiştir. Takım ömrü, diğer bir ifadeyle takım hasar mekanizmaları pek çok faktöre bağlı olarak değiştiğinden, kesme şartlarına bağlı olarak takım ömrünü belirlemek oldukça zordur. Takım ömrünü belirlemek için başvurulan önemli bir teknik; talaş kaldırma sırasında eş zamanlı olarak takım kesme şartlarının izlenmesidir. Bu amaçla yapılan araştırmalar, çalışmanın sonunda özetlenmiştir.

The main goal of this work is to study the influence of the tool failure mechanisms and on the tool life. Aiming to achieve this goal, several tool failure mechanisms are explained. Tool life is often the most important practical consideration in selecting cutting tools and cutting conditions. Tool wear and fracture rates directly influence tooling costs and part quality. For these reasons tool life is the most common criterion used to rate cutting tool performance and the machinability of materials. An understanding of tool life requires an understanding of the ways in which tools fail. Broadly, tool failure may result from wear, plastic deformation, or fracture. Cutting edges experience much higher normal and shear stresses than almost any other type of bearing surface and, at high cutting speeds, high temperature are also generated. The principle types of tool failure mechanisms, characteristics, countermeasures for common types of tool failure mechanisms and classified according to the regions of the tool they affect, are shown in Table 2. A primary goal of metal cutting research has been to develop methods of predicting tool life from a consideration of tool failure mechanisms. Unfortunately, accurately predicting tool life in any general sense is very difficult because tool failure mechanisms depend on several parameters. In this work, studying about online monitoring of tool condition methods are also explained.

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