Abdulkadir Güllü

Dynamic Chip Breaker Design for Inconel 718 Using Positive Angle Tool Holder

This study has focused on the chip-breaker design and experimental cutting of Inconel 718 with the designed chip breaker. The process of chip breakage for Inconel 718 with respect to cutting speed, depth of cut, and feed rate then chips and machined surfaces were analyzed from the experimental results. For this purpose, the nickel-based super alloy, Inconel 718, was machined with two layers PVD coated (TiAlN–TiN) carbide insert at feed rates of 0.10, 0.15, 0.20, 0.30 mm/rev, 0.5, 1, 1.5, 2 mm with depth of cuts, and 30, 45, 60, 75 m/min cutting speeds using developed dynamic chip breaker with positive tool holders in dry cutting conditions. Chip pictures and surface roughness (Ra) were recorded. Chip breakability during machining of the Inconel 718 depends on DC motor speed and chip breaker position on the cutting tool. The experimental results show that the designed chip breaker can break long chips at any cutting condition and acceptable surface finish can be achieved. In addition to this, according to cutting conditions, the usages of dynamic chip breaker on the surface of cutting insert are measured between 1% and 44% cooling effects.

The Analysis of Process Parameters for Turning Cobalt-Based Super Alloy Haynes 25 / L 605 Using Design of Experiment

Haynes-25 alloy (also known as L-605 alloy) is extensively used in the applications of aerospace industry, turbine and furnace parts, power generators and heat exchangers and petroleum refining components due to its excellent properties. However, machining this alloy is more difficult compared to normal steel or even stainless one because of its characteristics of hardness and strength. This paper presents experimental investigation into machining parameters in the turning process of Haynes 25 alloy using uncoated carbide tools. Design of experiment (DOE) has been used for studying the effect of the main turning parameters such as cooling condition, cutting speed and feed rate on the arithmetic average surface roughness (Ra) of Haynes-25 alloy. Tests are designed according to Taguchi’s orthogonal array. Experiments have been performed under dry cutting and conventional wet cooling. Minimum surface roughness was obtained in turning using uncoated tools under wet cooling condition at the cutting speed of 45 m/min and feed rate of 0.12 mm/rev.

Wear Model in Milling Compacted Graphite Iron with Different Lead Angle Using Ceramic Cutting Tools

The objective of this study is to reveal the influence of the lead angle variation on tool wear in the process of face milling of compacted graphite iron with ceramic cutting tools. To achieve this goal, 36 milling experiments were carried out with different lead angles, cutting speeds and feed rates at the 2.5 mm constant depth of cut. The tool flank wear was strongly affected by the lead angle variations. SEM analyses of the cutting inserts were performed and experimental results have been modelled with artificial neural networks (ANN) and regression analysis. A comparison of ANN model with regression model is also carried out. The R2 values for testing data were calculated as 0.992 for ANN and 0.998 for regression respectively. This study is considered to be helpful in predicting the wear mechanism of the ceramic cutting tool in the machining of compacted graphite iron. A quicker method for the estimation of tool life is proposed, which requires less consumption of workpiece material and tools.

Influence of Lead Angle Variation on the Coated Carbide Inserts Wear when Milling CGI and Modeling by Artificial Neural Networks and Regression Analysis Method

The aim of this research is to investigate the influence of lead angle, cutting speed and the maximum chip thickness on tool wear in face milling process of compacted graphite iron. Tool failure modes and wear mechanisms for all cutting tools were examined in respect of various cutting parameters and were evaluated on the base of the flank wear. SEM analyses of the cutting inserts were performed and experimental results have been modelled with artificial neural networks (ANN) and regression analysis. A comparison of ANN model with regression model is also carried out. Predictive ANN model is found to be capable of better predictions for flank wear within the range used in network training. The R2 values for testing data were calculated as 0.992 for ANN and 0.998 for regression analysis, respectively. This study is considered to be helpful in predicting the wear mechanism of the coated carbide insert in the machining of compacted graphite iron.

Dynamic Chip Breaker Design for Nickel-Base, Inconel 718, Alloy with Coated Carbide Tools Using Negative Angle Tool Holder

This study has focused on the chip-breaker design and experimental cutting of Inconel 718with the designed chip breaker. The process of chip breakage for Inconel 718 with respect to cutting speed, depth of cut and feed rate then chips and machined surfaces were analyzed from the experimental results. For this purpose, the nickel-base super alloy, Inconel 718was machined with a two layers PVD coated (TiAlN-TiN) carbide insert at feed rates of 0.10, 0.15, 0.20, 0.30 mm/rev, 0.5, 1, 1.5, 2 mm with depth of cuts, and 30, 45, 60, 75m/min cutting speeds using developed dynamic chip breaker with Negative tool holders in dry cutting conditions. Chip pictures and surface roughness (Ra) were recorded. Chip breakability during machining of the Inconel 718 depends on DC motor speed and chip breaker position on the cutting tool. The experimental results show that the designed chip breaker can break long chips at any cutting condition and acceptable surface finish can be achieved. In addition to this, according to cutting conditions, the usage of dynamic chip breaker on the surface of cutting insert is measured between 1% and 40% cooling effects using negative tool holder.