Mechanical and physical properties of hybrid reinforced (Al/B4C/Ni(K)Gr) composite materials produced by hot pressing

NAS, Engin/0000-0002-4828-9240WOS: 000354792300006In this study, the mechanical and physical properties of hybrid reinforced (Al/B4C/Ni(K)Gr) metal matrix composite (MMC) materials were investigated. The MMC materials were produced using the powder metallurgy (PM) production method of hot pressing (HP). The aluminum alloy Alumix 13 was used as matrix material and boron carbide (B4C) and nickel-coated graphite (Ni(K) Gr) as reinforcement elements. The microstructural characteristics, hardness, 3-point bending strength and density values of the produced hybrid reinforced MMC materials were determined. The reinforcement element B4C was kept at constant concentration of 8 wt.-%. Four different MMC materials were produced with the addition of 0, 3, 5 and 7 wt.-% Ni(K) Gr in the B4C. From the SEM images of the MMC materials produced by the HP technique, it was observed that the reinforcement element exhibited a uniform distribution. Moreover, the particles showed an approach to each other depending on the particle size and the amount (wt.-%) of the reinforcement element. With increasing graphite content in the structure density, hardness and 3-point bending test values decreased.Karabuk University Scientific Research Project DivisionKarabuk University [KBU-BAP-13/2-DR-012]The authors wish to place their sincere thanks to Karabuk University Scientific Research Project Division for financial support for the Project No.: KBU-BAP-13/2DR-012

EXPERIMENTAL INVESTIGATION OF THE TOOL-CHIP INTERFACE TMPERATURES ON UNCOATED CEMENTIDE CARBIDE CUTTING TOOLS

It is known that the temperature as the result of the heat developed during machining at the tool-chip interface has an influence on the tool life and workpiece surface guality and the methods for measuring this temperature are constantly under investigation. In this study, the measurement of tool-chip interface temperature using toolworkpiece termocouple method was investigated. The test were carried out on a AISI 1040 steel and the toolchip interface temperature variation was examined depending on the cutting speed and feed rate. The obtained groups show that cutting speed has more influence on the temperature than feedrate has

Termal bariyer kaplamanin motor yakit sarfiyati egzoz sicakliği ve emisyonlara etikilerinin deneysel olarak incelenmesi

Bu çalışmada, hava soğutmalı, tek silindirli, doğrudan püskürtmeli, 4 zamanlı ve marşlı Solax marka 178FE tipi dizel motorunun yanma odası elemanlarının termal bariyer malzemelerle kaplanması ve 1600 1/min ile 3200 1/min hızları arasında 400 1/min hız aralıklarında ve tam yük şartları altında % 100 dizel yakıtı ile denenmesi ve termal bariyer kaplamaların motorun egzoz gaz sıcaklığına, egzoz emisyonlarına ve yakıt sarfiyatına etkilerinin belirlenmesi amaçlanmıştır. Motor hızının artmasına ve kaplama malzemelerine bağlı olarak egzoz gaz sıcaklığının arttığı, çevreye ve canlılara zararlı olan HC ve CO emisyonlarının azaldığı ve yakıt sarfiyatında iyileşme olduğu tespit edilmiştir

Investigating the effects of cutting speeds over the built-up layer and built-up edge formation with SEM

Bu çalışmada, işleme parametrelerinden kesme hızının Yığıntı Katmanı (Built-Up layer) (YK) ve Yığıntı Talaş (Built-Up Edge) (YT) oluşumu üzerindeki etkileri araştırılmıştır. Bu amaçla, AA5052 alaşımı; kaplamasız karbür takımla bilgisayarlı sayısal denetimli (BSD) torna tezgahında, kuru olarak işlenmiştir. Deneylerde, beş farklı kesme hızı (100, 200, 300, 400, 500 m/min), sabit ilerleme hızı (0,30 mm/dev) ve sabit kesme derinliği (1.5 mm) işleme parametreleri olarak seçilmiştir. Talaş kaldırma işlemleri sonucunda, kesici takım üzerinde en fazla YK ve YT, 100 m/min kesme hızı ve 0,30 mm/dev ilerleme hızında yapılan talaş kaldırma işleminde oluştuğu tespit edilmiştir. Kesme hızının artırılması YK ve YT oluşumunu azaltmış, fakat denenen sınırlar içerisinde YK ve YT oluşumu engellenememiştir.In this study, the effects of cutting speed; over the formation of Built-Up Layer (BUL) and Built-Up Edge (BUE) were investigated. For this purpose, AA5052 alloy was processed on a Computer Numeric Control (CNC) lathe with uncoated cemented carbide insert in dry conditions. As processing parameters in the experiments, five different cutting speeds (100, 200, 300, 400, 500 m/min), constant feed rate (0,30 mm/rev) and connstant depth of cut (1,5 mm) were selected. As the result of the experiments, it was stated that BUL and BUE were formed on cutting tool mostly in machining at 100 m/min cutting speed and 0,30 mm/rev feed rate. Increasing the cutting speed decreased BUL and BUE formation but they could not be stopped in the tested range

The experimental investigation of the effects of uncoated cementit carbide insert and cutting parameters on surface roughness

Bu çalışmada, AISI 1030 çeliği bilgisayarlı sayısal denetimli (BSD) torna tezgahında, soğutma sıvısı kullanılmadan, kesme derinliği sabit tutularak (2 mm), değişik kesme hızı ve ilerleme hızı değerlerinde kesme işlemi gerçekleştirilmiştir. AISI 1030 çeliği kaplamasız sementit karbür kesici takımla işlenerek, kesme parametrelerinden kesme hızı ve ilerleme hızı değerinin yüzey pürüzlülüğüne etkisi araştırılmıştır. Deneylerde, 0.25 - 0.45 mm/dev arasında beş farklı ilerleme ve 100, 200 ve 300 m/dak kesme hızı kullanılmıştır. İlerleme değerinin % 80 azaltılmasıyla yüzey pürüzlülüğünde % 215 iyileşme sağlanmış, kesme hızının % 200 azaltılmasıyla ise % yüzey pürüzlülüğünde % 13 iyileşme elde edilmiştir.In this work, AISI 1030 steel has been machined on a CNC lathe without cutting fluid, at various cutting speed and feed rate values with a constant depth of cut. Effect of cutting speed and feed rate on surface rougness were investigated by machining AISI 1030 steel by a carbide insert without coating. In the experiments five different leed rate values between 0.25 and 0.45 mm/dev and three different cutting speed settings 100, 200 and 300 m/dak were used. It is found that at lower feed rates, lower surface roughness is and at higher cutting speeds, higher surface roughness values are obtained. The lessening of cutting speed about 80 % improves the surface roughness 215 %, by increasing the cut-off rate about 200 % obtained an improvement of 13% respectively

A review of cryogenic treatment on cutting tools

AKINCIOGLU, Sitki/0000-0003-4073-4837WOS: 000354629200021Enhancing the performance of cutting tools is an important factor in reducing production costs. Cutting tools are subjected to processes such as heat treatment and coating in order to improve their performance. Cryogenic treatment, which is also known as sub-zero heat treatment, has made significant contributions to the improvement of wear resistance, tool life, dimensional integrity, and product quality of cutting tools. The mode of application of cryogenic treatment and the type of cutting tool both affect tool performance. Therefore, it is necessary to examine the way cryogenic treatment is applied to cutting tools and its effects on their performance. This study reviews the literature on the performance of cryo-treated cutting tools