[en] Cadmium severely embrittles Zircaloy-2. The phenomenon was observed to occur with solid cadmium at 300/degree/C, liquid cadmium at 340/degree/C, and cadmium dissolved in liquid cesium over a range of temperatures. In liquid cesium alone at 300/degree/C, high reduction of area and only ductile fracture morphology was observed. The effect of texture was briefly evaluated using tensile samples machined from cross-rolled plate in different orientations. The results are presented in terms of fractography, and stress-elongation data obtained by constant extension rate tensile tests. 23 refs

[en] There are cases in surface fracture investigations in which one cannot use a direct micrographic surface fracture evaluation in the laboratory. The following work describes a technique enabling these evaluations indirectly via impressions. The quality of the impressions can be vastly improved when using 'lacquer matrixes' (dry-in matrixes), where the lacquer film is filled with technovite to strengthen it. This form of preparation with thin, technovite strengthened lacquer films which on the one hand, wet the fracture structures well in liquid state and on the other hand, can be removed in the solid state without too much sticking, enables evaluations to resolutions of approx.= 1 μm in the SEM investigations of the negative impressions. The characteristic microstructures for e.g. honeycombed fracture, cleavage, cyclic stress, H² embrittlement, stress crack corrosion and hot cracking can be clearly indentified. (orig.)

[en] Analysis of changes in fractographs quantitative indicators of the polymer composite fracture surfaces in the aging process in temperate continental climate is carried out on the basis of the offered technique. It is found out that the strength of polymer samples at tension depend on the square of the fracture surface mirror zone. (paper)

[en] The method is proposed to determine average rate of crack propagation under creep conditions based on complex analysis of flat sample fractures and diagrams of crack boundaries displacement. The method has been tested on 15Kh1M1FL cast steel. The presence of a 12 mm-deep, single-ended sharp notch on the sample and as sharp but not deep (1.0 mm) side grooves facilitates an abrupt suppression of plastic deformation in the fracture. It is determined that the proposed method gives results close to the data published earlier. The possibility is shown to investigate using the method crack propagation conditions at all stages (initial, accelerated and avalanche) during strong suppression of creep deformation

[en] Fractographic examinations have been performed on a series of miniature compact tension specimens of HT-9 tested at room temperature and below. Reductions in toughness found for these specimens are shown to be associated with transgranular cleavage fracture and are a function of the plastic deformation which occurs prior to the onset of brittle fracture

[en] Recent years have seen the emergence of a new engineering technique based on the statistical analysis of the topography of a fracture surface. While this technique follows in the footsteps of fractography, a science developed in the middle of the last century to interpret the shapes created when a part breaks, it pushes back the boundaries. By providing hitherto inaccessible information on the mechanical properties of a material and the conditions of its fracture, it now makes it possible to trace the thread of damage step by step to determine its causes. And so guide the development of safer materials and structures

[en] Fracture stress data obtained by tensile testing of circumferentially notched round tensile specimens made of 20MnMoNi55 and SA333 (Grade 6) steels at different subzero temperatures down to −150 °C have been analysed following Weibull statistics. It is observed that between −50 and −100 °C the mean Weibull modulus of 20MnMoNi55 steel obtained by employing linear regression technique over the complete range of data population for every test temperature increases in a perfectly linear manner with lowering of test temperature. A sharp decrease in the modulus value with further decrease of test temperature to −150 °C is observed. The data population for −50 and −70 °C, however, do not agree well with single straight-line relationship of Weibull statistics. In case of SA333 (Grade 6) steel nearly two fold increase in the value of mean Weibull modulus is observed on lowering of test temperature from −100 °C to −150 °C. Scanning electron fractography reveals different failure modes in both the steels depending upon test temperatures

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No abstract available

[en] A fractographic method for estimating the fatigue life of IKhI3, IKhI3Sh, EhI415, 30KhMA steels in corrosive medium in the course of cyclic loading by testing the laboratory samples for fatigue and drawing fatigue curve sigma=f(N) and the dependence Ksub(1c)sup(sc)=F(N) is proposed