The tool wear evaluation has a very strong impact on the product quality as well as efficiency of themanufacturing process. This paper presents the further development of an innovative and reliable direct measuringprocedure for measuring spatial cutting tool wear. The influence of the orientation of measurement head accordingto the measurand was examined. Based on the analysis of measurements accuracy and the amount of capturedreliable data, the optimal setup of the measuring system was defined. Further a special clamping system wasdesigned to mount the measurement device on the machine tool.To test the measurement system tool life experiment wereperformed, where cutting tool wear was measured directlyon machine tool. The results showed that novel tool wear diagnostic represent objective estimation, performed on amachine tool that provides higher productivity and quality of the machining process.
COBISS.SI-ID: 13336347
The development of cutting simulation still requires an improvement in the understanding of the frictional phenomena at the tool-work material interface. This paper introduces a method for a fast identification of friction and heat partition models, based on a special tribometer able to simulate wide ranges of contact pressures and sliding velocities, similar to those occurring along the tool-work material interface in cutting. The method is applied for a wide spectrum of work materials and lubrication conditions. Combined with an analytical post-treatment, this set-up provides a modelling of the frictional behaviour that may improve significantly thermal aspects in cutting simulations.
COBISS.SI-ID: 12859163
A simple method with high efficiency for generating high pure hydrogen by hydrolysis in tap water of highly activated aluminum dross is established. Aluminum dross is activated by mechanically milling to particles of about 45 um. This leads to removal of surface layer of the aluminum particles and creation of a fresh chemically active metal surface. In contact with water the hydrolysis reaction takes place and hydrogen is released. In this process a Zero Waste concept is achieved because the other product of reaction is aluminum oxide hydroxide (AlOOH), which is nature-friendly and can be used to make high quality refractory or calcium aluminate cement. For comparison we also used pure aluminum powder and alkaline tap water solution (NaOH, KOH) at a ratio similar to that of aluminum dross content. The rates of hydrogen generated in hydrolysis reaction of pure aluminum and aluminum dross have been found to be similar. As a result of the experimental setup, a hydrogen generator was designed and assembled. Hydrogen volume generated by hydrolysis reaction was measured. The experimental results obtained reveal that aluminum dross could be economically recycled by hydrolysis process with achieving zero hazardous aluminum dross waste and hydrogen generation.
COBISS.SI-ID: 12247579
In this paper, the influence of hard coatings (nanolayer AlTiN/TiN, multilayer nanocomposite TiAlSiN/TiSiN/TiAlN, and commercially available TiN/TiAlN) and cutting parameters (cutting speed, feed rate, and depth of cut) on cutting forces and surface roughness were investigated during face milling of AISI O2 cold work tool steel ( 61 HRC). The experiments were conducted based on L27 OA factorial design by response surface methodology, and response surface equations of cutting forces and surface roughness were obtained.
COBISS.SI-ID: 25973287
This paper presents results of the influence of cryogenic machining on the process stability. The stability diagrams are obtained experimentally using the coarse-grained entropy rate estimator for chatter detection from measured cutting forces. In comparison with conventional machining, enlarged stability windows are observed for the case of cryogenic machining. Based on the defined specific force models in turning operations, it is shown that a higher machining stability is achievable in cryogenic machining due to the reduction of specific cutting force components, in comparison with dry machining.
COBISS.SI-ID: 11827739