Tools for crushing of undesirable advance growth and mulching wood are subjected to heavy wear in operation with the need for their frequent replacement shortly after deployment. It is important to address the problem of their wear due to price of tools, as well as the time necessary for their replacement. Tool life is shortened because of deformation taking place due to the loss of wolfram-carbide (WC) tips, what is an undesirable phenomenon. Solutions for increasing the tool lifetimes were designed on the basis of analysis of wear mechanisms that cause this deformation. Furthermore, effect of deformed layer was evaluated by measuring hardness and microhardness. It was found that there was a strain hardening the surface due to cyclic loading. Size and extent of deformation of the entire tool with the loss of material on the functional part were documented using an optical scanning sensor system. Effect of the deformation on the material structure change, as well as topography and extent of surface area affected by abrasive wear under impact loads, were assessed by means of light and electron scanning microscopy. On the basis of these analyses, an option for increasing the lifetime of exposed areas on the tool by application of hardfacing to increase the tool wear resistance was proposed. Prerequisite for extending their work lifetime in the field is creation of a sufficient coarse layer or multiple layers of wear resistant material at specific tool areas.

This paper presents a utilization of mulcher tools, their wear and possibilities of increasing their lifetime and durability based on analysis and tests. Mulcher tools are subjected to a very strong wear causing the loss of soldered WC tips in some cases and even permanent deformation of the body tool made of steel 14 220 (16MnCr5) during the continuous use. Images depicting the loss of material from the mulcher tool due to wear were produced by overlaying the pre- and after-wear tools by means of the optical scanning system. Input analyses - measuring of hardness, impact test and evaluating of microstructure showed that forging is without heat treatment. This does not provide sufficient mechanical properties to tools that would ensure work continuation after losing WC tips. Therefore, an appropriate process of heat treatment of the tool body has been proposed. By comparing the loss of material using abrasive test, it was observed that the wear of heat-treated material was three times lower than of material without heat treatment. This gives the precondition for increasing the resistance of the tool body and thus increasing of lifetime and durability after loss of WC tips. The implementation of such a solution could bring not only technical but also economic benefits.

The article is aimed at verifying the state of a real workplace using virtual reality. In analyzing the readiness of virtual reality applications, augmented reality was selected for the following work. The most significant advantage of augmented reality is the implementation of a virtual model and the ability to deal with the analysis in a real environment, which is particularly beneficial in the case of production plants. In the first phase of the work, an analysis of the current state of the workplace was carried out, where the requirements for the design of the new workplace were specified. This was followed by the phase of design preparation in 3D modeller. At this very stage it appeared to be advantageous to use virtual reality applications; in the design process, regular approval procedures are required as for an expert team (management, design, quality, ...), which puts high qualification requirements on the readiness of this team. In this phase, the 3D design of the new workplace was inserted into the application supported by augmented reality and some options were indicated to deal with the ergonomic and risk analysis. The result of this work is, in particular, an extension of options in designing and analyzing production workplaces and machinery in multidisciplinary teams.

The energy absorption at crash, usually described by stiffness and crashworthiness, is the key request for the car-body components, considering the material they were made from. The modified 3-point bending test with fixed ends has been developed in our department to assess materials for the carbody parts. The force and punch path are measured and used to calculate stiffness and crashworthiness. Experiments were performed on high strength low alloyed steel H220PD, dual phase steel DP 600 and austenitic stainless steels AISI 304 for base material and specimens welded by solid state fiber laser YLS-5000. Based on the experiments and analysis, the austenitic stainless steel is better to use for car body components of frontal deformation zones. Otherwise, the passenger's compartment is better protected by applying dual phase steel for car body parts when side impact occurs.

<p>The article is focused on the use of Quality Management tools to identify causes of formation deviations dimensions in cylinder head castings. Moreover,  methods of production of castings made from alloy AlSi9Cu1,  heat treatment of castings, as well as requirements of their quality are described. Research of the influence heat treatment parameters on the changes of castings' dimensions, with using Quality Management tools (Ishikawa diagram) is described too. In order to optimize the process for eliminate of deviations,  experiment for modelling  parameters of heat treatment was designed. The results processed in the Pareto diagram clearly pointed out the causes. Dimensional deviations were created during the heat treatment process. We have found the largest distortions in castings were created during rapid cooling.The article gives important information about using of research results in the production of cylinder head castings.</p>