Marek Sadílek

Surface Roughness after Machining and Influence of Feed Rate on Process

The aim of the work is find out influence of feed rate on the quality for the machined surface, especially surface roughness. The experiment was carried out by cutting tool HURCO VMXt30 with respect to the following cutting parameter: cutting speed 250; 350; 450; 550 and 850 m.min-1, feed 0,1; 0,5 and 1,0 mm/tooth. For testing was used two most common materials in the steel grade 1.1191 (12 050) and 1.2343 (19 552), and we chose two ordinary parameters of surface roughness; Ra - arithmetical mean roughness deviation and Rz - the largest inequalities height profile in the transverse direction and the longitudinal direction of machining. The structural equations will be the result which can describe the character depending on the cut surface parameters.

THE EFFECTIVENESS OF STRATEGIES PRINTING PRINTER EASY 3D MAKER

The article tackles the possibilities and effectiveness of different printing strategies on Easy 3D MAKER printer. This printer uses Fused Deposition Modeling (FDM) method. The operating software of the 3D printer offers various settings, which influence the quality and efficiency of printing. In the article there is described the printing of a sample with all fillament print strategies available in the 3D maker software. The fillament print strategy of the printed model fundamentally influences the consumption of printing material and time at printing the component. The consumption of printing material was assessed indirectly by weight of particular printed samples. For each printing strategy there were 5 samples printed out. The Octagramspiral strategy resulted as the best in material consumption aspect. The most effective strategy in printing time perspective is the Concentric strategy.

The effect of feed rate on durability and wear of exchangeable cutting inserts during cutting Ni-625

Rad se bavi postupkom rezanja super legure nikla i odabirom odgovarajucih parametara rezanja za njezino lako i ucinkovito rezanja. U eksperimentalnom dijelu predlažu se tri izmjenljive plocice i određuje ucinak parametra posmaka tijekom obrade na trajnost i trosenje reznog alata. Ovisno o izboru posmaka rezanja i kolicini trosenja tih izmjenljivih plocica, procijenjena je kvaliteta tokarene povrsine i određeni parametri visine hrapavosti. U zavrsnom dijelu iznosimo opažanja do kojih smo dosli tijekom obrade Inconel 625, određujemo ucinak posmaka na trajnost i trosenje plocica, procjenjujemo i preporucujemo prakticne korake, opisujemo mehanizme trosenja reznog klina, određujemo trajnost alata i hrapavost tokarene povrsine.

The Influence of Motor Skills on Measurement Accuracy

Abstract This innovative study trying to do interdisciplinary interface at first view different ways fields: kinantropology and mechanical engineering. A motor skill is described as an action which involves the movement of muscles in a body. Gross motor skills permit functions as a running, jumping, walking, punching, lifting and throwing a ball, maintaining a body balance, coordinating etc. Fine motor skills captures smaller neuromuscular actions, such as holding an object between the thumb and a finger. In mechanical inspection, the accuracy of measurement is most important aspect. The accuracy of measurement to some extent is also dependent upon the sense of sight or sense of touch associated with fine motor skills. It is therefore clear that the level of motor skills will affect the precision and accuracy of measurement in metrology. Aim of this study is literature review to find out fine motor skills level of individuals and determine the potential effect of different fine motor skill performance on precision and accuracy of mechanical engineering measuring.

Identification of Tool Wear when Machining of Austenitic Steels and Titatium by Miniature Machining

Abstract Application of miniature machining is currently rapidly increasing mainly in biomedical industry and machining of hard-to-machine materials. Machinability of materials with increased level of toughness depends on factors that are important in the final state of surface integrity. Because of this, it is necessary to achieve high precision (varying in microns) in miniature machining. If we want to guarantee machining high precision, it is necessary to analyse tool wear intensity in direct interaction with given machined materials. During long-term cutting process, different cutting wedge deformations occur, leading in most cases to a rapid wear and destruction of the cutting wedge. This article deal with experimental monitoring of tool wear intensity during miniature machining.

Influence of Machining and Heat Treatment on Deformations of Thin-Walled Bearings

Paper deals with identification of the main causes of deformations of the thin-walled bearings and comprehensive analysis of the causes of bearing deformation and suggestion of the possible solutions. It deals with the analysis of bearing steel, its characteristics and causes of deformation of bearing rings during heat treatment and manufacturing process. Provides experimental measurement and report of uniformities on the surface of bearing rings - called oval and cradle, metallographic analysis of rings, as well as an analysis of various processes affecting the formation of deformations.

Locking Compression Plate for Distal Tibia Fractures

This article represents a multidisciplinary approach to biomechanics (engineering + medicine) in the field of distal tibia fractures. The objective of the present study was to carry out a strength and reliability assessment of a medial plate for the treatment of distal tibia fractures. This was performed via numerical modelling (FEM) and experimental methods (compression test and Electronic Speckle Pattern Interferometry – ESPI method). The plate is used for internal fixation in orthopaedics and traumatology. Analyses were performed for non-fused bone with comminuted fracture in the distal metaphysis (i.e. unsuccessful treatment, where all loads in the metaphysis are carried by the plate). An anatomical tibia model (based on CT images in Mimics software) was used for FE analysis. In the experiments, the bone was replaced with a shaped piece of spruce wood (based on Mimics software) and the plate was loaded until its failure (major plastic deformation). Numerical and experimental results were evaluated and compared.

Hard Machinable Machining of Cobalt Super Alloys

Abstract The article deals with difficult-to-machine cobalt super alloys. The main aim is to test the basic properties of cobalt super alloys and propose suitable cutting materials and machining parameters under the designation 188 when machining. Although the development of technology in chipless machining such as moulding, precision casting and other manufacturing methods continues to advance, machining is still the leading choice for piece production, typical for energy and chemical engineering. Nowadays, super alloys are commonly used in turbine engines in regions that are subject to high temperatures, which require high strength, high temperature resistance, phase stability, as well as corrosion or oxidation resistance.