Abstract: Titanium alloy Ti6Al4V represents one of the most frequently used alloys in medical as well as in aerospace industry and is considered as a difficult to cut material. In this paper, cutting experiments within throughput drilling were carried out under the varying cutting speed, feed and tool geometry (cutting edge radius and clearance angle). The effects of cutting speed feed and tool geometry on thrust force in drilling Ti6Al4V alloy were investigated applying design of experiment (DoE) according to Taguchi plan L16. The effect of above mentioned parameters was investigated through analysis of the S/N ratios (smaller is better) and ANOVA analysis. All analyses were performed using statistical software Minitab and Matlab. In the case of thrust force, the feed is the main influencing factor, followed by cutting speed, cutting edge radius and clearance angle.
Abstract: The paper focuses on tool wear and surface roughness indicators evaluation associated with hole making of nickel based super alloy Inconel 718 widely used in aero engine industry. Within study of tool wear and surface integrity, series of experimental tests were performed on an Inconel 718 specimen. Special attention was paid to ensure that the cutting conditions correspond to the industrial practice. Two steps of hole making sequence consists of a drilling process applying a twist drill that removes most of the stock. This operation is followed by a second machining process, typically applying a face – cutting finisher (reamer), which removes an additional (radial) stock between 0.1 mm to 0.25 mm per side. Tool wear appeared predominantly as flank wear VBmax and evolution of surface roughness Ra and Rz has a similar trend for drilling and finishing.
Abstract: The article deals with comparison and evaluation of the milling strategies that are available in CAM systems and are used to produce components with freeform surfaces. For the purpose of the experiment, sample with freeform features was designed to employ different milling strategies when 3 axis machining. Evaluation of the milling strategies was carried out by surface roughness measurement, comparison of the actual machining time with a simulation time as well as visual control of the sample surface with a surface obtained in simulation. Acquired research results can be utilized within production process of tools with sculptured surfaces, such as tools for metal sheet forming, dies, molds for plastics and many others.
Abstract: There is a difference in machining by the cutting tool with defined geometry and undefined geometry. That is one of the reasons of implementation of hard turning into the machining process. In current manufacturing processes is hard turning many times used as a fine finish operation. It has many advantages – machining by single point cutting tool, high productivity, flexibility, ability to produce parts with complex shapes at one clamping. Very important is to solve machined surface quality. There is a possibility to use wiper geometry in hard turning process to achieve 3 – 4 times lower surface roughness values. Cutting parameters influence cutting process as well as cutting tool geometry. It is necessary to take into consideration cutting force components as well. Issue of the use of wiper geometry has been still insufficiently researched.
Abstract: The paper deals with the tribological properties of investigated types of hard-faced materials at erosive wear process. Influence of inclination angle of elements on friction resistance and microhardness changes of hard-faced layer were investigated too. From quantitative aspect were hard-faced layers evaluated on the base of weight loses. From achieved results follow that inclination angle is one from determining factors on to material’s wear measure.
Abstract: The paper presents the application of weld layers used in renovations of functional surfaces of components that are exposed to several tribodegradation factors in operation of metallurgical and engineering industries. Surfaces of selected components are renovated using arc welding processes, namely: (MMAW) Manual Metal Arc Welding, (SAW) Submerged Arc Welding methods, (GMAW) Gas metal arc welding and (FCAW) Flux cored wire metal arc welding without gas shield. Claddings were made always three-layered directly on the surfaces of renovated components using dedicated cladding machines in operations and laboratory conditions respectively. Their quality was assessed using non-destructive tests, namely (VT) visual testing by STN EN ISO 17637 and (UT) Ultrasonic testing STN EN ISO 11666. Within the destructive tests the quality of claddings was evaluated using the metallographic analysis conducted on a light microscope Olympus BX and electron microscope Jeol where the impact of mixing the weld metal as well as heat treatment after cladding on the final structure of claddings was observed. Using the Shimadzu HMV 2 device the microhardness of cladding layers was evaluated on metallographic samples by STN EN ISO 9015-2. In laboratory conditions the resistance of cladding layers to abrasive wear was verified on the device Di-1. Experimental testing of the claddings confirmed that the selected additives and cladding parameters witting individual technology were chosen correctly as in cladding layers no presence of internal defects was observed.
Abstract: 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.
Abstract: Application of beam welding methods for joining austenitic, duplex and other stainless steels is the right choice which not only lowers weld joint degradation but increases the production efficiency. There are many different demands on butt joints of duplex steels. One of them is equal ratio between austenite and ferrite of weld metal, because it can significantly influence the weld joints performance in real environment. The aim of this paper is to evaluate the influence of filler material on mechanical and technological properties of weld joints made from stainless steel SAF 2507.
Abstract: During of aluminum alloy materials, it is possible to find three surface types which can be distinguish as primary, secondary and tertiary sections. In practice this is a big problem in case of finding the basic parameters of roughness and waviness as described by ISO 4288. According to our research, it is possible to use optical microscopy in the first step and subsequently to scan the surface in 3D in order to distinguish the type of. Another problem is how to determine the boundaries between the individual structures. The article describes methods to distinguish the boundaries in a more precise way by the cumulative functions, leading to more accurate determination of the surface quality parameters.