Download or read book Irradiation effects on fatigue crack propagation in austenitic stainless steels written by D. J. Michell and published by . This book was released on 1977 with total page 22 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Neutron Irradiation Effects on Fatigue Crack Propagation in Type 316 Stainless Steels at 6490C written by Donald Joseph Michel and published by . This book was released on 1980 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Neutron Irradiation Effects on Fatigue Crack Propagation in Type 316 Stainless Steels at 649 C written by and published by . This book was released on 1980 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt: The fatigue and creep-fatigue crack propagation performance of Type 316 stainless steel was investigated following fast neutron irradiation to a fluence level of about 5 x 10 to the 22nd power n/sq. cm (> O.1 MeV), about 26 displacements per atom (dpa), at 649 C. The results from fatigue tests of both annealed and 20 percent cold worked steel show that irradiation produced no significant effect on crack propagation rate when compared with unirradiated steel tested at 649 C. For tests conducted using creep-fatigue cycling, the inclusion of a two-minute hold time at the maximum cyclic load resulted in a marked increase in the crack propagation rate of the annealed steel. The effect of a one-minute hold time in the 20-percent cold worked, irradiated steel was to significantly increase the crack propagation rate at 649 C. Scanning electron microscope examination of the tested specimens revealed that the crack propagation mode of the specimens which exhibited increased crack propagation rates was primarily intergranular while a transgranular mode was observed for specimens with lower crack propagation rates. The results point toward a synergistic relationship between thermochemical history, precipitate formation, and hold time effects as the responsible mechanism for the crack propagation performance. (Author).

Download or read book Effect of Neutron Irradiation on Fatigue Crack Propagation in Types 304 and 316 Stainless Steels at High Temperatures written by P. Shahinian and published by . This book was released on 1973 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt: Resistance to fatigue crack propagation of pre- and postirradiation AISI Types 304 and 316 stainless steels was determined at 800 and 1100 F (427 and 593 C) using the fracture mechanics approach. The effect of irradiation on fatigue resistance was dependent upon test temperature and irradiation conditions. In general, irradiation degraded fatigue resistance at 1100 F (593 C) but at 800 F (427 C) enhancement as well was observed. In both steels irradiated in a thermal reactor to a fluence of 1.8 x 1021 n/cm2 >0.1 MeV, fatigue crack growth rates at 800 F (427 C) were lower than in the unirradiated steels for a given stress intensity factor range (?K). However, at 1100 F (593 C) the effect was reversed and crack growth rates were higher in the irradiated steels. Irradiation in a fast reactor to a fluence of ~1.2 x 1022 n/cm2 >0.1 MeV caused fatigue crack growth rates at 800 F (427 C) to increase at low values of ?K and decrease at high values of ?K. At 1100 F (593 C) the crack growth rates in the irradiated steel were either the same as or higher than in the unirradiated steel. The influence of irradiation on fatigue life generally reflected the effect observed on crack growth rate.

Download or read book Fatigue Life and Crack Growth Predictions of Irradiated Stainless Steels written by Robert William Fuller and published by . This book was released on 2018 with total page 156 pages. Available in PDF, EPUB and Kindle. Book excerpt: One of prominent issues related to failures in nuclear power components is attributed to material degradation due the aggressive environment conditions, and mechanical stresses. For instance, reactor core support components, such as fuel claddings, are under prolonged exposure to an intense neutron field from the fission of fuel and operate at elevated temperature under fatigue loadings caused by start-up, shut-down, and unscheduled emergency shut-down. Additionally, exposure to high-fluence neutron radiation can lead to microscopic defects that result in material hardening and embrittlement, which significantly affects the physical and mechanical properties of the materials, resulting in further reduction in fatigue life of reactor structural components. The effects of fatigue damage on material deterioration can be further exacerbated by the presence of thermal loading, hold-time, and high-temperature water coolant environments. In this study, uniaxial fatigue models were used to predict fatigue behavior based only on simple monotonic properties including ultimate tensile strength and Brinell hardness. Two existing models, the Bäumel-Seeger uniform material law and the Roessle-Fatemi hardness method, were employed and extended to include the effects of test temperature, neutron irradiation fluence, irradiation-induced helium and irradiation-induced swellings on fatigue life of austenitic stainless steels. Furthermore, a methodology to estimate fatigue crack length using a strip-yield based model is presented. This methodology is also extended to address the effect of creep deformation in a presence of hold- times, and expanded to include the effects of irradiation and water environment. Reasonable fatigue life predictions and crack growth estimations are obtained for irradiated austenitic stainless steels types 304, 304L, and 316, when compared to the experimental data available in the literature. Lastly, a failure analysis methodology of a mixer unit shaft made of AISI 304 stainless steel is also presented using a conventional 14-step failure analysis approach. The primary mode of failure is identified to be intergranular stress cracking at the heat affected zones. A means of circumventing this type of failure in the future is presented.

Download or read book Fatigue Crack Propagation in Fast Neutron Irradiated Stainless Steels and Welds written by P. Shahinian and published by . This book was released on 1975 with total page 14 pages. Available in PDF, EPUB and Kindle. Book excerpt: Neutron irradiation to a fluence of 1.2 x 1022 neutrons (n)/cm2, > 0.1 MeV caused a small decrease in the resistance to fatigue crack propagation of Types 308 and 316 submerged-arc weld metals at 800 and 1100°F (427 and 593°C). Nevertheless, the postirradiation fatigue resistances of the weld metals were generally comparable to those of the corresponding base metal. Fatigue crack growth in Types 304 and 316 base metals were also affected by irradiation; the effect was dependent on the stress intensity factor and temperature. Although resistance to crack growth of cold-worked (25 percent) Type 304 stainless steel was only slightly reduced at 800°F by irradiation, the resistance at 1100°F was reduced markedly.

Download or read book Effect of Neutron Irradiation on Fatigue Crack Propagation in Types 304 and 316 Stainless Steels at High Temperature written by P. Shahinian and published by . This book was released on 1972 with total page 19 pages. Available in PDF, EPUB and Kindle. Book excerpt: The resistance of pre- and postirradiated AISI Types 304 and 316 stainless steels to fatigue crack propagation was determined at 800 and 1100F (427 and 593C) using the fracture mechanics approach. The effect of irradiation on the fatigue resistance of these steels was dependent upon test temperature and irradiation conditions. (Author).

Download or read book Irradiation Effects on Reactor Structural Materials written by Lendell E. Steele and published by . This book was released on 1974 with total page 60 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report, covering research for the period, 1 February to 31 July 1975, includes: (1) the effect of hold time on fatigue crack propagation in neutron irradiated Type 316 stainless steel; (2) the simulation of irradiation-induced creep in nickel; (3) the elastic plastic toughness of Type 316 stainless steel forging; (4) swelling in dilute binary alloys; and (5) the influence of delta ferrite content on notch toughness of austenitic stainless steel weldments.

Download or read book The Impact of Inelastic Deformation Radiation Effects and Fatigue Damage on Fusion Reactor First Wall Lifetime written by Robert David Watson and published by . This book was released on 1981 with total page 418 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Effects of Neutron Irradiation on Fatigue and Creep Fatigue Crack Propagation in Type 316 Stainless Steel at 649 C written by DJ. Michel and published by . This book was released on 1981 with total page 23 pages. Available in PDF, EPUB and Kindle. Book excerpt: The fatigue and creep-fatigue crack propagation performance of Type 316 stainless steel has been investigated following fast neutron (n) irradiation to fluence levels of ~1.5 x 1022 and ~5 x 1022 n/cm2 (>0.1 MeV), ~6 and 26 displacements per atom (dpa), respectively, at 649°C. The purpose of this work was to evaluate the effects of neutron fluence and temperature on the crack propagation resistance and failure mode of the steel. The results from fatigue tests of the annealed steel show that irradiation to both fluence levels at 649°C produced no significant effect on the crack propagation rate when compared with unirradiated steel tested at 649°C. For the 20 percent cold-worked steel, however, irradiation to the lower fluence level increased the crack propagation rate while at the higher fluence level the crack propagation rate was only slightly increased relative to the unirradiated material. For tests conducted using creep-fatigue cycling, the effect of a 1-min hold time at the maximum cyclic load was to produce a marked increase in the crack propagation rate of the annealed steel irradiated to the lower fluence level. At the higher fluence level, the inclusion of a 2-min hold time in the creep-fatigue cycle resulted in a further increase in the crack propagation rate. The effect of a 1-min hold time in the irradiated, 20 percent cold-worked steel was to significantly increase the crack propagation rates, particularly at the low fluence level at 649°C. Scanning electron microscope examination of the fracture surfaces of the tested specimens revealed that the failure mode of the specimens which exhibited increased crack propagation rates was primarily intergranular while a transgranular mode was observed for specimens with lower crack propagation rates. The results point toward a synergistic relationship between thermomechanical history, precipitate formation, and hold time effects as the responsible mechanism for the crack propagation performance.

Download or read book Effect of Neutron Irradiation on Fatigue Crack Propagation in Type 316 Stainless Steel at 649C written by and published by . This book was released on 1979 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt: The effect of fast neutron irradiation on the fatigue crack propagation performance of Type 316 stainless steel was investigated at 649C and compared with previous results at 593C. The results show that, during continuous cycling, no significant effect of irradiation on crack propagation rate was observed in annealed steel. The inclusion of a one minute hold time increased the crack propagation rates in the irradiated annealed steel when compared with the results at 593C. Irradiation was found to increase the crack propagation rates in 20 percent cold worked steel during both continuous cycling and one minute hold time tests. Scanning electron microscopy (SEM) examination of the fracture surfaces of the unirradiated fatigue specimens revealed that intergranular carbide precipitation during testing at 649C acted to delay the transition to a purely intergranular failure mode with hold time as previously observed at 593C.

Download or read book Effects of Radiation on Substructure and Mechanical Properties of Metals and Alloys written by and published by ASTM International. This book was released on 1973 with total page 546 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Interpretation of the influences of irradiation upon fatigue crack propagation in austenitic stainless steels written by G. J. Lloyd and published by . This book was released on 1982 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Fatigue Crack Propagation in Austenitic Stainless Steels at Cryogenic Temperatures written by Zequn Mei and published by . This book was released on 1990 with total page 230 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Effects of Radiation on Materials written by D. S. Gelles and published by ASTM International. This book was released on 1996 with total page 1169 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Fatigue Crack Growth of Low Fluence Neutron Irradiated Stainless Steel DIN 1 4948 written by MI. de Vries and published by . This book was released on 1982 with total page 15 pages. Available in PDF, EPUB and Kindle. Book excerpt: Compact-tension (CT) specimens of stainless steel DIN 1.4948, which is similar to AISI Type 304, have been irradiated up to a fluence level of 2.1024 n.m.-2 (E > 0.1 MeV) at temperatures ranging from 330 to 823 K. Post-irradiation constant-load-amplitude crack propagation (fcp) tests were performed in air at temperatures from 298 to 823 K with frequencies ranging from 10-3 to 10 Hz and R-ratios (min. load/max. load) of 0.05 and 0.30. Irradiation hardening after the low temperature irradiations (573 K and below) caused a reduction of the fatigue crack growth rate. Irradiation at the higher temperatures did not affect the fcp at the high frequency of 10 Hz. At 823 K the combination of high R-ratio and low frequency (10-2 Hz) resulted in an increase of the post-irradiation crack growth rate with a factor 10. This irradiation effect is attributed to the observed intergranular crack propagation.

Download or read book Effects of Radiation on Materials written by and published by ASTM International. This book was released on with total page 767 pages. Available in PDF, EPUB and Kindle. Book excerpt: