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This article deals primarily with the problem of determining the cutting force when machining hardened steels. For this study, the steel used was 100 Cr6, number 1.3505. The secondary aspects of the study focused on the evaluation of the surface quality of machined samples and the recommendation of cutting conditions. A wide variety of components are used in engineering, the final heat treatment of which is hardening. These components are usually critical in a particular product. The quality of these components determines the correct functioning of the entire body of technical equipment, and ultimately, its service life. In our study, these are the core parts of thrust bearings, specifically the rolling elements. The subject of this experiment involves machining these components in the hardened state with cubic boron nitride tools and the continuous measurement of the cutting force using a dynamometer. The machining is carried out on a conventional lathe. A total of 12 combinations of cutting conditions were set. Specifically, for three cutting speeds of 130, 155 and 180 m·min−1, the feed rates of 0.05 and 0.1 mm·rev−1 and the cutting widths of 0.2 and 0.35 mm, were evaluated The evaluation assessed the surface quality by both touch and non-touch methods. A structural equation with the appropriate constants and exponents was then constructed from the data obtained using the dynamometer. The experiment confirmed the potential of achieving a value of the average arithmetic profile deviation Ra in the range of 0.3–0.4 when turning hardened steels with cubic boron nitride. [ABSTRACT FROM AUTHOR]

The paper deals with the production of a prototype of aesthetic eye prosthesis using procedures related to reverse engineering technology. Due to the complexity of the prosthesis shape, the 3D model was obtained by scanning a hand-made acrylic prosthesis on the ATOS Compact Scan. Following the pattern of manual production, the model geometry underwent a modification in 3ds Max software, where a planar surface was created in the selected area for the iris texture. By this shape change, the core of the prosthesis prototype was created. Using the UV mapping, the texture of the iris was placed on the surface of the model, which was obtained by modifying a photo from a slit camera. The core of the prosthesis prototype was printed on a full-color 3D printer Stratasys J750, which uses additive PolyJet technology based on the curing of photopolymers. In order to form a biocompatible surface, the printed core was embedded in a clear acrylate in a mold made using an original acrylate prosthesis. The paper concludes with an overall evaluation of the achieved results with a description of problematic production steps and a proposal for a procedure for the future production of prostheses by 3D printing. [ABSTRACT FROM AUTHOR]

The article deals with data in the cutting process of wood-based materials. The cutting process influences the shape and dimensions of a cutting edge. The experiments were focused on monitoring the changes of the cutting edge in machining of particle board and the influence of cutting speed on the tool wear. Cutting tests were performed during milling at cutting rates in the range 7.95 to 17.9 m/s (477 to 1074 m/min), a depth of cut of 9.5 mm, and a tooth feed of 0.05 mm. The wear process of cutting wedge during particle board milling is characterized by a decrease in the cutting edge of insert blades. The comparative digital dial gauge was used for measurement of the cutting wedge recession. The course of the wear of wood based materials exhibited similarity in graphical representation with abrasive material cutting. The resulting dependency may be used for selection of the most suitable cutting conditions according to operator requirements. [ABSTRACT FROM AUTHOR]

The paper deals with the analysis of the finishing of very precise holes by the applied MT3 reaming head from FINAL Tools Inc. In the case of a narrow range of customers with particularly high demands on the quality of the holes is currently appearing effort to elaborate a detailed evaluation of surface quality through evaluation of surface integrity. These facts led to the design of an experimental part in the form of an analysis of the surface integrity of the test holes machined by the reaming head MT3 during its durability. Surface integrity was assessed from the point of view of circularity, cylindricality, surface roughness, surface defects controlled by electron microscopy, microhardness and metallographic analysis of lateral extrusion. For the completeness of the measured parameters, the dimension of the reamed test holes was also measured. [ABSTRACT FROM AUTHOR]

Reverse engineering is a technology that enables acceleration of data acquisition for CAD, CAM, CAE systems and thus greatly reduces the time of development, design and production of components. In general, reverse engineering technology can be considered as the conversion of analog data to digital data, which is further processed. Individual industries are still increasing their demands for accuracy, size, quality, and so, therefore the use of digitization is found in many manufacturing areas such as the automotive, aerospace, shipping, medicine, industrial design, design, and so on. The paper deals with the analysis of the prototype component of the agitator gearbox in the form of a rough and chip-machined casting. The inspection of the shape of the gearbox consisted in reading the reference CAD model, establishing the digitized shape with respect to this reference model, checking the dimensions and creating a color map of the variations at selected points. [ABSTRACT FROM AUTHOR]

Well designed storage facility is the heart and soul of every logistic system. The subject of detailed storage solution and layout is so far inadequately covered. My goal was to create a software program that would support companies in their selection of ideal types of storage racks and pallets to store various materials on inside their warehouse. For this purpose, I've decided to specifically focus on the concept of weight load and storage capacity utilization as an optimal criteria as part of a system application. This criteria belongs to the most important vantage points according to which storage equipment is selected in real practice. In today's market, there exist a great deal of companies that offer various types of racks and pallets. The structure of available data however (e.g. company e-catalogues) is highly diverse and as a result doesn't offer automatic processing and devising. This is why I have made it my goal to design a clear cut database which stores only those parameters of racks and pallets that are important for work with a computer system when searching for an optimal solution. The actual structure of the proposed database, lets the computer program choose optimal racks and pallets from stored data, conduct capacity calculation of a warehouse as well as draw a possible layout of the proposed number of racks and pallets stored inside a storage facility. The key solution for creating similar computer programs is in fact a well designed database of specific objects (e.g. pallets) used in technological planning. [ABSTRACT FROM AUTHOR]

The issue of tool wear in the machining of non-metallic materials is a very under-researched area. The theory is based on the findings known in metals and is extended by interaction of the tool with wood-based materials. These materials have completely different properties, most of them are characterized by poor thermal conductivity and a different behaviour in different directions of load (axial, radial and tangential). The course is based on a tool wear in the wear curves. Criterion wear defines the maximum wear - a period corresponding to the working state of edge. Studying the process of wear is monitored mainly due to determine dependencies between the durability of the cutting tool and the cutting speed. Addiction is characterized by Taylor's relationship. Determination of tool life vs. cutting speed (T - vc ) is the starting basis for determining machinability . It is a material property that characterizes its suitability for machining. Measurement of tool wear in metal materials was carried out mainly on the back or top rake. However, for non-metallic materials, this wear is negligible and difficult to measure. This article is focusing on the issue of defining and measuring the radial edge wear. [ABSTRACT FROM AUTHOR]

This article discusses the issue of hardened steel machining. Many components in the engineering industry use hardening as the final heat treatment. These components usually occupy a significant position in a given assembly unit. They guarantee the correct operation of the entire technical equipment in total cooperation with other components. The quality of these components depends on the integrity of their surface. The production of these parts is usually carried out by traditional technological procedures. Clearly, an example of such a technology is grinding. However, this article discusses the application of other finishing technologies using a tool material made of cubic boron nitride (CBN). The technology used is finishing turning with subsequent tumbling technology. The subject of the evaluation is the integrity of the surface. In this part of the experiments, there are mainly individual parameters of surface roughness. Compared components are bearing rings, in this case the inner surface of the housing ring. [ABSTRACT FROM AUTHOR]