Key Engineering Materials Vol. 669

Abstract: The work presents results of diffusion niobizing of titanium Grade 2 by gas-contact method. Microhardness, thickness, chemical composition and microstructure were investigation. Diffusion processes was carried out in a two powder mixture. First consisted of ferro-niobium, kaolin and ammonium chloride, second mixture contained pure niobium instead ferro-niobium. The processes were carried out at 950°C, 1000°C and 1050°C for 2, 4 and 6 hours. Due to the geometric surface structure quality and other properties like thickness or microhardness, the best diffusion layer was obtained using first powder mixture and following parameters: temperature 950°C and time of diffusion equal 2 hours. The diffusion layer established in these conditions, had structure of niobium solution in titanium, and niobium content of about 10%. Its hardness was 550 HV0.05 while thickness was 120 μm.

Abstract: The paper deals with the monitoring of utility properties of new coating type on the basis of Zn/Mg (ZM). For the comparison there was used commonly used coating in the series production of car-body panels on the basis of zinc (Z100). Measured results markedly contribute to improve production systems of car-body adhesion bonding on the basic of performed evaluation of applied coatings types utility properties quality with regard to influence of temperature and corrosion environment. Testing was carry out by T-peel test acc. to ISO 11339 when such type of loading represents crucial bonding fracture type. Thus results reveal information about behavior of adhesive joints strength properties together with the type of fracture as a criterion for suitable application of new coatings types on the basis of Zn/Mg and their implementation into series production of automobiles.

Abstract: Abrasive water jet technology is among the unconventional ways of machining. In today's modern and progressive era is often used for cutting and machining of various types of materials because of lower costs and environmental impact, as the cutting tool is water, in our case, with the addition of abrasives. Objective of the measurements was to evaluate the impact of vibration on the technological head in abrasive water jet technology in changing the selected technological parameters and the flow rate of technological head. In the given experiment, the used material - steel Hardox 500 with a thickness of 10 mm. The effort was to investigate the effects of changes in the speed rate of technological head (by speeds - 40, 200, 400 mm / min) on the size of the vibration acceleration amplitude and its frequency. Based on the measured values ​​of vibration to the technological head create the database and from it is evaluated the data in selected softwares (LabVIEW, SignalExpress and Microsoft Excel). Findings and conclusions are formulated on the basis of graphical dependencies, envelopes frequency spectra and comparison chart of envelopes.

Abstract: The automation of hydroerosion manufacturing processes comes to increase the demands on engineering works in the preparation of production, at shortening of deadlines for implementation of scientific knowledge into practice, at the design of production processes and at the economization in production processes. This process is associated with extensive utilisation of mathematical methods, using of computational procedures for specific tasks and at the utilisation of methodology of mathematics for methods of formulating solutions. During the solving of problem, there is mostly used: operational analysis, set theory, theory of structures, theory of algorithms and languages.

Abstract: Separation of materials is a fundamental technology for the production of machine parts. Division is involved in the overall use of the material and also impact on the overall production time. With the development of new materials increasing requirements for the construction, design and durability. This makes the development of new materials with higher mechanical, physical and chemical properties. These materials are difficult to machine, and this gives rise to the development of non-conventional technologies, which include water jet technology.

Abstract: The submitted paper presents a technical system for vibration measuring, processing and evaluating The technical system is presented as a part of a survey which main goal was to find out an influence of working conditions on creation and extend of vibration within production systems. The work introduces a demonstrational example of measured, processed and evaluated data of an experiment where parametres of vibrations, which were created due to water jet technological head parametres changes, were scanned.

Abstract: The article is focused on the evaluation of the effects of factors of the high-speed hydro-abrasive stream technology during the splitting of construction steels 12 050 and 11 523 through a factor experiment. The experiment examined the effect and significance of two selected factors (type of material and movement speed of the technological head). Measured results are depicted through graphic and numerical relations, based on which new knowledge and recommendations for operators is formulated.

Abstract: The paper describes abrasive kind and granularity change impact to technology head vibration generating during cutting of seven selected investigated kinds of steel by means of AWJ technology. The investigation of abrasive granularity impact is carried out for three speeds of the technology head shift. A set of 3D comparative graphs of vibration parameter relations for seven analyzed kinds of steel from graphical records of vibration acceleration amplitude to frequency relation was created. On the base of the comparative graphs a discussion about results is generated and conclusions are defined. The work presents a thematically integrated part of a dissertation results and completes a group of recent knowledge focused on production systems working state diagnostics with the water jet technology.

Abstract: AWJ abrasive water jet belongs to the unconventional methods of machining. Waterjet offers a number of advantages over other cutting methods. There is no heat or chemical material damage, high accuracy and precision, the ability to cut any material and others. Despite many advantages of AWJ has some technical elements that can be improved and optimized. This article deals with effect of vibration on the technological head and consequently wears. The aim of the experiments is to find the most appropriate feed rate, which extends the life of the technological head.

Abstract: The paper presents a database programme which was created on the base of the search focused on working condition impact to generating and extend of vibrations at AWJ technology production systems. The database programme serves for less complicated, but mainly quicker and more effective searching of an optimal combination of technological parametres to get minimal values of vibration parametres during AWJ technology selected materials cutting. The work presents a thematically integrated part of a dissertation.