The effect of 0.2% addition of Mg, Co and Ce to 99.9% cast aluminium was studied by evaluation of changes in microstructure and mechanical properties. The microstructure was analyzed by scanning electron microscopy and transmission electron microscopy. The Al99.9 alloy contained only Al-Fe-Si phase particles. Similar Al-Fe-Si particles were observed in alloy with 0.2% Mg addition, because this amount of magnesium was fully dissolved in the solid solution. The addition of cobalt resulted in the formation of Al9.02Co1.51Fe0.47 phase particles assuming the shape of eutectic plates. The electron backscattered diffraction map made for the alloy with 0.2% Co addition showed numerous twin boundaries with distances between them in the range from 10 to 100 µm. The addition of cerium was located in the grain boundary area. Cerium also gave rise to the formation of two types of particles, i.e. Al4Ce and Al-Ce-Fe-Si. The Al-Ce-Fe-Si phase is a nucleation site for the Al4Ce phase, which forms eutectic plates. The results showed that the introduction of additives increases the mechanical properties of the cast materials. The 99.9% cast aluminium has a hardness of 16.9 HB. The addition of 0.2% by weight of Mg, Co, Ce increases this hardness to 21.8 HB, 22.6 HB and 19.1 HB, respectively.

The aim of the study was to test and assess products extruded from the magnesium alloys type MgAlZn: AZ31, AZ61 and AZ80A alloys in the form of Ø35mm round bars and 80x15mm flat bars. The test material was extruded in a direct system with the ram feed speed of 1 mm/s and the extrusion ratio λ = 7 ÷ 9. The extruded bars were examined in as-extruded state and after heat treatment to the T5 temper and T6 temper. The strength properties were tested and microstructure was examined with calculation of the average grain size.

The aim of the study was to test and assess products extruded from the magnesium alloys type MgAlZn:AZ31, AZ61 and AZ80A alloys in the form of empty set35mm round bars and 80x15mm flat bars. The test material was extruded in a direct system with the ram feed speed of 1 mm/s and the extrusion ratio lambda = 7 divided by 9. The extruded bars were examined in as-extruded state and after heat treatment to the T5 temper and T6 temper. The strength properties were tested and microstructure was examined with calculation of the average grain size.

Studies of composite nickel coatings electrolytically deposited on aluminium alloys with different content of vanadium were described. Composite coatings were deposited from a Watts bath containing fine-dispersed SiC powder particles in an amount of 20 g/l and organic matters such as saccharin and sodium laurate. The morphology, structure and thickness of the obtained composite coatings were presented. The corrosion resistance of produced coatings was examined by electrochemical method. Basing on the results of studies it was found that coatings obtained with the sole addition of saccharin were characterized by numerous surface defects. The addition of sodium laurate eliminated the occurrence of defects caused by hydrogen evolution and the resulting coatings were continuous with good adhesion to the substrate. The distribution of the ceramic SiC phase in coatings was fairly uniform for all the examined variants of aluminium alloys. SEM examinations did not reveal the phenomenon of the ceramic particles agglomeration.

Studies of composite nickel coatings electrolytically deposited on aluminium alloys with different content of vanadium were described. Composite coatings were deposited from a Watts bath containing fine-dispersed SiC powder particles in an amount of 20 g/l and organic matters such as saccharin and sodium laurate. The morphology, structure and thickness of the obtained composite coatings were presented. The corrosion resistance of produced coatings was examined by electrochemical method. Basing on the results of studies it was found that coatings obtained with the sole addition of saccharin were characterized by numerous surface defects. The addition of sodium laurate eliminated the occurrence of defects caused by hydrogen evolution and the resulting coatings were continuous with good adhesion to the substrate. The distribution of the ceramic SiC phase in coatings was fairly uniform for all the examined variants of aluminium alloys. SEM examinations did not reveal the phenomenon of the ceramic particles agglomeration.

The problem of calculations and experimental validation of residual stresses in hot-rolled strips is considered in the paper. Residual stresses become of practical importance when the laser cutting of strips is applied. The goal of this paper is development and experimental validation of a model of residual stresses in hot-rolled strips based on the elastic-plastic material model. The models of elastic-plastic deformation during cooling of hot rolled strips during laminar cooling and in the coil were developed. Elastic-plastic properties of the material were determined experimentally using tests on GLEEBLE 3800. Industrial testing of residual stress in strips after cooling in coil was performed. For measurement of residual stress in strips the X-ray diffraction method was used.

The paper presents the results of the die forging tests of a modified EN AW-6101 alloy with the addition of Zr, using two types of the feedstock materials. The first feedstock materials were ingots cast in a vertical semi-continuous process, the second feedstock materials were extruded rods. The die forging process was carried with parameters enabling “on line” heat treatment (T5 temper). For comparison, forgings were also heat treated to the T6 temper and to thermo-mechanical treated to the T8 and T9 temper. Then forgings made from both feedstock materials were characterised in terms of structure, mechanical properties and electrical conductivity.

The structure and properties of AZ61 alloy after deformation by ECAE were characterised. Alloy structure was examined after the successive passes of ECAE process, to study the effect of deformation on the morphology of gamma phase precipitates and the size and shape of grains. Based on EBSD analysis, the occurrence of high angle boundaries was stated. An attempt was made to describe the mechanisms that are operating when the deformation route is changed at 300 degrees C in the AZ61 alloy processed by ECAE method. Alloy hardness after the first cycle of deformation was stabilised at the level of 80-90 HB. Based on the hardening curve and the occurrence of high angle grain boundaries (>15 degrees), the possibility of further deformation of the AZ61 alloy was confirmed.

The object of this study was to develop parameters of plastic deformation process of magnesium alloy - ZK60A. The tests have showed that for this alloy it is possible to use the temperature of the plastic deformation process ranging from 350 degrees C to 450 degrees C. Samples were characterized by mechanical properties and structure in different heat treatment tempers. This magnesium alloy obtained in the T5 temper higher mechanical properties then T6 temper. The paper also presents research results of investigation of conversion coating on ZK60A magnesium alloy by anodic oxidation method in non-chromium solutions. It was found that the coating produced in non-chromium solutions show considerable increase of corrosion resistance of tested alloy.

One of the most important characteristics of the material allowing us to predict its applicability for specific tasks as a single object or as an integral part of the whole structure is the presence of stresses. There are many methods to measure stress. Among them, increasingly important and recognised as the most accurate non-destructive method is the X-ray measurement technique. The aim of this study was validation of the results obtained by the X-ray stress measurement method. Stress measurements were performed on samples of the three materials subjected during measurement to the effect of tensile forces. Studies revealed close relationship between the stress values measured by X-ray technique and actual values present in the examined material. The summation of residual stresses present in the material and stresses caused by the effect of external forces was observed.

The object of this study was to develop parameter of the die forging process, such as feedstock temperature and to investigate her impact on the structure and mechanical properties of magnesium alloys in different heat treatment conditions. Tests were carried out on a 2,5MN maximum capacity vertical hydraulic press using forgings of sample ( model) shapes. Then, based on the results obtained in previous work, research was carried out to develop for items forged from magnesium alloys the parameters of heat treatment to the T5 and T6 condition in the context of achieving possibly homogeneous and fine-grained structure and, consequently, high mechanical properties.

The object of this study was to develop parameter of the die forging process, such as feedstock temperature and to investigate her impact on the structure and mechanical properties of magnesium alloys in different heat treatment conditions. Tests were carried out on a 2,5MN maximum capacity vertical hydraulic press using forgings of sample (model) shapes. Then, based on the results obtained in previous work, research was carried out to develop for items forged from magnesium alloys the parameters of heat treatment to the T5 and T6 condition in the context of achieving possibly homogeneous and fine-grained structure and, consequently, high mechanical properties.

The article consists test results of direct extrusion AZ80A & ZK60A magnesium alloys. Extrusion process was conducted in the temperature range 350 degrees C-450 degrees C at different extrusion speeds (ram speed 0.8 mm/s and 2.8 mm/s). In order to find optimum precipitation strengthening parameters the aging curves have been made. Extruded rods were characterized by mechanical properties in different tempers. Basic structure researches of magnesium alloys have been made.

The paper presents the results of the investigation of the influence of duration and temperature of tempering process on the magnetoacoustic properties of P91 tempered martensite ferritic steel. During tempering of martensitic steels the dislocation density, which initially is very high, systematically decreases what is confirmed both by analysis of the width of X-ray diffraction peaks and hardness measurements. Magnetic hysteresis loops undergo a systematic change resulting in the monotonous decrease of magnetic “hardness” of the investigated samples. The influence of the tempering time on the Barkhausen noise (BN) and magnetoacoustic emission (MAE) signals intensity was investigated in order to verify the possibility of application of those methods for a nondestructive monitoring of heat treatment quality. Barkhausen noise signal envelopes change their shape very strongly during the initial stages of tempering, yet the overall signal intensity is weakly affected. As for the magnetoacoustic emission a very strong increase of its intensity is observed for almost all the tempering times and temperatures. It was concluded that the MAE signal intensity is a suitable parameter for the evaluation of tempering time, as for the BN signal the envelope shape analysis would be necessary for such a purpose.