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The improvement of the microgeometry became a subject of a great interest in cutting tools optimization. This paper approaches the process of cutting edge preparation of solid carbide reamers. It has been analyzed the evolution of cutting edge wear resistance in the material GGG 40 using the scanning electron microscope (SEM). The work also compared the rounded cutting edge reamers realized using wet abrasive jet machining with standard unprepared cutting edge. To obtain different microgeometries were experienced a number of machining strategies, which resulted in four combinations of roundness and forms for the cutting edge. In order to validate the results, the author studied the wear resistance during the reaming tests, the influence of prepared surface of the cutting edge on metallic coating layer adhesion. The final purpose was to determinate the optimal strategy of cutting edge preparation considering the evolution of wear during the reaming process.

Abstract. The goal of this paper is to determine the optimal cutting edge microgeometry for a carbide end mill used in stainless steel machining. The optimal cutting edge microgeometry will be determined through conducting more tool life tests. Tools with three different cutting edge radiuses and one without edge preparation will be tested in order to determine the influence of the cutting edge microgeometry on the wear and tool life. The edge microgeometry is obtained through wet blasting preparation.

It's known that the durability of the cutting tool is influenced by the cutting parameters. In the recent years, scientists turn their research efforts to demonstrate that the microgeometry have an important role in determining the durability of the cutting tools. The processes studied most are milling and turning, but few researches have been done on the drilling operation. In this paper is presented the influence of 6.8 mm diameter drills with three values of the K-factor, but the same radius of the cutting edge and same macrogeometry. To obtain the desired microgeometry of the drills, two preparing technologies of the cutting edge were used. Drills were tested in two types of materials: X5CrNi18-10 (1.4301) and 42CrMo4 (1.7225). The main goal of this paper is to observe the influence of the microgeometry in the drilling process namely the durability and wear evolution.

Abstract. Generally the study, evaluation and general understanding of end milling cutters are complicated by the complexity of the cutting process and of the cutting tool. The main performance factor of the end milling cutters is given by the durability of the tool. In practice the sound analysis of the tool engaged in the cutting process is used as a simple predictability mean to forecast the future durability of the tool. An alternative or complementary tool to predict future durability is the investigation of the chip behaviour. Chip behaviour investigations can also give clues concerning the possible improvement of the cutting tools. The current article presents a detailed chip behaviour investigation for 5-fluted end milling cutters with different performances and various geometries when approaching different types of metal cutting operations in 42CrMo4 alloy steel. Current study can be applied in future researches regarding the evaluation and the development of end milling cutters. Furthermore the current approach can be used on other types of cutting tools.

In this paper are presented and analyzed a series of problems that are appearing during the CFRP machining. Due to their properties, the composite materials began to replace traditional materials (ferrous and non-ferrous) in a lot of industries leading out the development of new methods of machining or adaptation of the classic. Unlike traditional material, drilling in CFRP is more difficult due to inhomogeneity of the material, its high hardness but also due to lack of knowledge relating to how these materials behave. This paper investigates different types of tool wears as corner wear, welding, crater wear that are appearing in drilling operation due to the highly abrasive nature of the carbon fibers. Also, here is presented an evaluation that refers to the machined hole quality and describe defects as delamination, pull outs, fibers projections, pyrolysis and shape errors. The main goal of this paper is to verify the current status of technique in CFRP drilling in order to develop and produce a new drill geometry in a cooperation between the Technical University of Cluj-Napoca and the cutting tool company Gühring KG.

This study presents new machining types of advanced materials. Super alloys, ceramics and fiber reinforced plastics started being used on a large scale in the last period, this making necessary the development of new machines and machining processes. This paper describes different methods of ultrasonic machining and makes a comparison between them. By ultrasonic machining can be understood a process that involves axial vibrations with a high frequency and low amplitude, for improving the machining conditions like chip flute removal, tool wear and temperature reducing. In this paper, are presented three different ultrasonic machining methods. In the first one, the cutting process is made by abrasive slurry inserted between the tool and the workpiece, in the second one is made by a rotating diamond-brazed tool and in the last one is made by a special drill. This paper aims to study the current status in this field in order to make a research program through collaboration between the Technical University of Cluj-Napoca and the tool company Gühring KG by which to develop ultrasonic drilling.