Showing papers in "Materials Science and Engineering in 1981"

TL;DR: In this article, an energy-based method of local elastic-plastic stress and strain calculation is presented, where the theoretical stress concentration factor k t can be related to the unit elastic strain energy at a notch root.

TL;DR: The role of grain boundaries in corrosion product scales as short-circuit transport paths for the outward diffusion of metal and the inward ingress of oxygen, sulfur and carbon needs to be clarified.

TL;DR: In this article, the authors analyzed the Portevin-Le Chatelier effect by measuring the stress drop Δσ and found no agreement between the theory and the experimental results for a ferritic stainless steel.

TL;DR: In this paper, the influence of powder characteristics, dopant addition, sintering atmosphere, firing schedules and the intrinsic grain boundary properties on microstructural development are discussed, and it is concluded that particle coarsening and rapid grain growth during densification must be minimized, possibly by dopant additions and a control of the sinting atmosphere.

TL;DR: In this article, the high temperature steady state deformation behavior of PbSn eutectic alloy was investigated over wide ranges of grain size (9.7 − 32.0 μm), temperature (298 − 443 K) and strain rate (10 −7 − 10 −2 s −1 ), after stability of microstructure and strength had been achieved through prior tensile deformation.

TL;DR: In this paper, the precipitation behavior of a PH 13-8 Mo stainless steel was investigated in the temperature range 450 − 575 °C using optical microscopy, transmission electron microscopy and X-ray diffraction techniques.

TL;DR: In this paper, the authors used deformation mechanism maps for a 1CrMoV steel to describe damage formation under high temperature cyclic-hold test conditions and used a grain boundary sliding regime to indicate the onset of wedge crack formation.

TL;DR: In this paper, the effects of the applied strain amplitude and crystal orientation on rapid hardening in fatigue were explored by constant-strain-amplitude tests on copper single crystals.

TL;DR: In this article, the experimental results of a study on the self-diffusion coefficients of both components in the f.c.d. phase of the FeNi binary system were presented.

TL;DR: Pipe diffusion can be important in a number of creep mechanisms, including diffusional, grain boundary sliding and slip creep as mentioned in this paper, and is predicted to be especially important for the creep of fine-grained materials at intermediate stresses and temperatures.

TL;DR: In this paper, the diffusion coefficients for the components in the f.c. phase of the binary systems FeCr and NiCr were measured using 59 Fe, 63 Ni and 51 Cr radioisotopes.

TL;DR: In this article, a study was made of the near-threshold fatigue crack propagation behavior of a wrought nickel-base superalloy, Rene 95, with reference to the effect of crack size on the threshold stress intensity ΔK0 no detectable crack growth.

TL;DR: In this article, the slip step behavior can be explained by the glide of groups of like-handed screw dislocations in the persistent slip bands (PSBs) and is not consistent with a model in which any significant part of the strain is due to edges bowing out of the PSB walls.

TL;DR: In this paper, different cell sizes of foamed or cellular glass were tested in tension (the Brazil test), flexure and compression at various stress rates, and it was observed that the strength increased with stress rate and also varied with the macrostress state.

TL;DR: In this article, the authors found a direct correlation between the atomic radius and the increase in crystallization temperature, and the effect is related to the viscosity of the alloy.

TL;DR: In this article, the low cycle fatigue behavior of Rene 77, a nickel-base superalloy, was studied at 927 °C and it was found that even though the precipitate structure is stable with respect to thermal exposure, reversed plastic deformation had the effect of producing rapid coarsening which was associated with cyclic softening.

TL;DR: In this article, an X-ray diffraction technique was used to measure the residual stresses of an aluminum matrix-graphite fiber composite, and the results can be related to interface structures and transverse properties of the composites.

TL;DR: In this article, the authors report measurements of the lives of crystals which have different orientations for strains in the plateau range using tension-compression tests; the results show that Coffin-Manson behavior actually occurs.

TL;DR: The current state of understanding of shape memory behavior is reviewed in this paper, where the authors present a review of the state-of-the-art shape memory models and their interrelationships.

TL;DR: In this article, arc-melted molybdenum was fully recrystallized and annealed below 1100 K under various atmospheres and they were tested by bending.

TL;DR: In this article, the cyclic hardening and softening behavior of Cu-2.0at.%Co, Cu-1.4at.%.Co and Al 2.1 at.%Mg was studied in the underaged and peakaged states on single crystals at plastic stran amplitudes ranging from 5.5 × 10−5 to 7.8 × 10 −3.

TL;DR: In this article, the relationship between melt puddle length and ribbon thickness in spin casting of Fe81.5B14.5Si4 amorphous ribbons is analyzed with a continoues casting model to estimate the ribbon formation temperature Tt and the metal wheel interfacial conductance h.

TL;DR: In this article, the electrical conductivity of graphite fiber-epoxy resin composites was measured for samples containing 64 or 65 vol% of carbon fibers, and the measured conductivity results from contact between neighboring fibers due to an irregular arrangement and was based on the random resistor network model of Kirkpatrick.

TL;DR: In this paper, the microstructures developed after normalizing and tempering 0.5Cr0.25V ferritic steels and the changes which occur during service in electricity-generating plant.

TL;DR: In this article, the authors show that dislocation profiles extending from the grain boundaries, and associated with ledges on the boundary plane, increase in frequency (the number of profiles per unit length of grain boundary plane) with increasing strain.

TL;DR: In this article, a wall structure on {100} planes is discussed in terms of multiple slip in polycrystalline Cu-Ni alloys fatigued to saturation using transmission electron microscopy.

TL;DR: In this paper, the critical grain size for microcracking in Al2O3 was estimated by a method, based on fracture mechanics, which predicts a linear relationship between the temperature TMB at which micro-cracking begins and the reciprocal square root of the grain size.

TL;DR: In this paper, the effect of reactive and non-reactive ceramic inclusions on the low cycle fatigue life of low carbon Astroloy subjected to hot isostatic pressing was studied at 25 °C and at 500 °C.

TL;DR: In this article, the development of geometric imperfections in tensile deformation was re-examined with particular attention to the influence of the temperature sensitivity of the flow stress.