The paper concerns the effect of annealing time and temperature on the properties of the nitride layer on X37CrMoV51 tool steel used in the extrusion aluminium industry. Samples made from X37CrMoV51 steel were hardened and tempered, and then nitrided at 530 °C. After nitriding, the samples were annealed in a furnace at 470 °C for 8 h, 12 h, 24 h, 30 h and 60 h, and additionally for 20 h at 270 °C. The samples were tested for structure, hardness and abrasion immediately after nitriding and again after annealing. It was found that annealing the nitrided samples leads to degradation of the nitride layer, accounting for the decrease of hardness. The annealing of the samples at 470 °C, over 12 h causes a decrease in mean hardness value from 1176 HV to 1103 HV, and annealing the samples over 30 h at this temperature leads to a decrease in hardness to 964 HV. The changes in nitrogen content in the white (compound) and diffusion layers and the resulting consequences of changes in phase composition and properties were evaluated. Annealing over 30 h at 470 °C caused the white layer to disappear and the average nitrogen content in the diffusion layer to decrease to the level of about 5–6 at%.

This paper presents a study on the perspectives of structure refinement of aluminum and its alloys by reciprocating extrusion (cyclic extrusion compression—CEC). The study included Al99.5 and Al99.992 aluminum and AlMg5 and AlCu4Zr alloy. Aluminum and alloys were deformed by reciprocating extrusion (CEC) in the strain range ϕ = 0.42 (1 CEC cycle) to ϕ = 59.8 (67 CEC cycles). After deformation, the structure of the specimens was investigated by optical microscopy (OM) and transmission electron microscopy (TEM), which revealed that the primary mechanism of hardening, over the range of applied strains, was the result of the propagation of shear bands throughout the specimens. The intersection of shear bands was found to divide the volume of the specimens into nano and microvolumes with dimensions limited by the width of the microbands. Due to structure renewal processes such as polygonization and dynamic geometric recrystallization, the formed micro and nano volumes were transformed into nano and micrograins with large misorientation angles. In terms of the occurrence of grain microstructure, a sustained uniform level of hardening was found, which was defined as steady-state flow. The research has shown that the steady state of flow is a result of the competitive interaction between the processes of hardening and structure renewal. The higher the metal purity, the higher the intensity of the structure renewal processes was. The formation of new grains and their growth under dynamic and post-dynamic recrystallization was observed in Al99.992 aluminum, in which high purity of the metal and high strain accumulation caused the growth of new grains at room temperature.

The article investigates the effect of temperature and annealing time on the surface quality of WNLV nitrided steel used for the production of dies for extrusion of aluminum alloys. Eight annealing variants were tested, differing in the total annealing time at temperatures of 460 °C and 590 °C. The results show the effect of the annealing time on the width of the diffusion layer, which increased with the increasing length of the annealing time. The hardness decreased as the annealing time increased. It was found that annealing of the steel causes its oxidation. The oxide layer formed consisted of two layers, more specifically, an Fe2O3 oxide layer and a lower Fe3O4 oxide layer adhering to the steel surface. The surface of sections pressed on oxidized matrices was tested. The roughness of the surface of the oxide layers was also tested. The research revealed that an increase in the surface roughness of the oxides deposited on the matrices causes an increase in the roughness of the extruded sections. These results can potentially be used to improve the efficiency of the extrusion process and the quality of the extruded sections.

Assessment and management of risk constitute the subject of many researches. Nevertheless, many more specific factors are applicable during the implementation of innovative technological projects. On the article identified risk factors, which have been supplemented, systematized and assigned to the individual risk categories. The risk assessment methods for R&D projects have been analysed, as well as the risk sheets have been developed for the R&D project through the use of dotProject application. Also shown that networking and clustering is a change for fruitful cooperation within difference EU projects, which create trust between business and sciences and reduce the risk.

This chapter describes and analyzes the 6xxx aluminum alloys used in the shape extrusion sector dedicated to automotive and construction industry. The division and application of 6xxx aluminum alloys are performed. The precipitation hardening of 6xxx (Al-Mg-Si) alloys is presented as these alloys easily undergo deformation and present the potential for new kinds of alloys for high-speed extrusion. The mechanisms of strengthening are shown with the evolution of precipitation sequences. Also some examples of industry applications of 6xxx aluminum alloys are presented.

The paper concerns the effect of annealing time and temperature on the properties of the nitride layer on X37CrMoV51 tool steel used in the extrusion aluminium industry. Samples made from X37CrMoV51 steel were hardened and tempered, and then nitrided at 530 • C. After nitriding, the samples were annealed in a furnace at 470 • C for 8 h, 12 h, 24 h, 30 h and 60 h, and additionally for 20 h at 270 • C. The samples were tested for structure, hardness and abrasion immediately after nitriding and again after annealing. It was found that annealing the nitrided samples leads to degradation of the nitride layer, accounting for the decrease of hardness. The annealing of the samples at 470 • C, over 12 h causes a decrease in mean hardness value from 1176 HV to 1103 HV, and annealing the samples over 30 h at this temperature leads to a decrease in hardness to 964 HV. The changes in nitrogen content in the white (compound) and diffusion layers and the resulting consequences of changes in phase composition and properties were evaluated. Annealing over 30 h at 470 • C caused the white layer to disappear and the average nitrogen content in the diffusion layer to decrease to the level of about 5-6 at%.