Showing papers in "Metallography in 1988"

TL;DR: Upon increasing the precipitate size by prolonged aging, the microstructure of the martensite in aged specimens recovers to that observed in solution-treated specimens.

TL;DR: In this paper, the appearance of premartensitic transitions in an aged Ti-51at%Ni shape memory alloy has been studied by means of electrical resistance measurements, and electron diffraction and microscopy.

TL;DR: In this paper, the evolution of reverse-transformed austenite in a maraging Fe-19.5Ni-5Mn alloy was examined using transmission electron microscopy.

TL;DR: In this paper, the fracture toughness of 304 austenitic stainless steel was measured from the dimple size at the bottom of the cup portion in the fracture surface of round tension samples, employing SEM techniques and quantitative fractography.

TL;DR: In this article, the effect of electropolishing variables of time, bath temperature, and composition of electrolyte on the corresponding current density-voltage potentiometric curve were studied on 1 Cr, 1 2 Mo, T11 steel.

TL;DR: In this article, the authors compared a number of reagents used in studying Fe-C-Mo alloys, having carbon contents ranging from 0.08 to 0.27 wt% and molybdenum contents from 1.25 to 4.28 wt%.

TL;DR: In this paper, the authors present an analysis of the stereological problem of estimating the distribution of sizes and shapes of creep cavities from cavity measurements taken on polished plane sections, subject to the assumptions that the cavities may be represented as collections of oblate spheroids and that the shape and orientation of the spheroid is known a priori.

TL;DR: In this paper, les superalliages a base de nickel sont predisposes a la fissuration a chaud dans la zone thermiquement affectee, attribuee a la segregation du carbure de niobium dans les alliages forges et des phases de laves dans le alliage moules.

TL;DR: In this article, the effect of different heat treatments on the microstructure of powder metallurgical compacts has been studied and a detailed analysis of the sintering behavior has been made.

TL;DR: In this paper, the formation of a plastic deformation zone with fatigue crack propagation was observed and analyzed with surface roughness and etch-pit techniques on a macro scale, and both techniques were calibrated with respect to plastic strain in order to characterize the strain distribution within the plastic zone.

TL;DR: In this article, the melting of an Al-5 wt.% Co alloy has resulted in the formation of a supersaturated solid solution at very high cooling rates as obtained in the gun technique.

TL;DR: In this article, a new duplex phase FeAl10Mn29C0.4 stainless steel alloy has been developed as a substitute for the conventional duplex Fe-Ni-Cr stainless steels.

TL;DR: In this article, the pucker mechanism was used to increase the number of secondary cells in Fe-Zn alloys with 20 and 25 wt.% zinc, and the secondary cells were observed to nucleate at three different regions; namely, the original position of the grain boundary, the impinged region of two primary cells, and at the interface between the migrating cell boundary and original position.

TL;DR: The formation of butterfly martensite may not be a single continuous process, but rather a compound one comprised of separate stages as mentioned in this paper, where crossed or kinked thin-plate martensites are formed.

TL;DR: In this paper, the limitations of conventional reagents for the metallographic preparation of nickel-based alloys and, in particular, of the IN-657 alloy, which is the object of this study, are revealed.

TL;DR: In this paper, the authors present a computer program for the automatic plotting of standard projections of crystals of arbitrary lattice parameters, with any wanted central pole, in a given lattice.

TL;DR: In this article, feature-specific measurements of test circles of known size were conducted at different magnifications using a stored image of the detected circles (256 × 256 picture points within the guard frame).

TL;DR: In this paper, a box dimension method is developed to characterize the fractal behavior of the tungsten phase boundary of WNiFe presintered materials and powder allgomerates.

TL;DR: The microstructures of nominally stoichiometric ingots of Ni 3 Al with boron contents up to 1.12 at.% were examined in the as-received and in the homogenized states as discussed by the authors.

TL;DR: In this article, a study of the microstructural evolution during thermal aging was made on two heats of 12Cr-1Mo steel (HT-9) at various temperatures from 500 to 800°C for times of 30-10,000 h.

TL;DR: In this article, a stereological estimator is developed for the estimation of the sum of the squares of the areas of plane convex loops per unit volume, from the measurements performed on the plane of polish.

TL;DR: La methode est basee sur une attaque electrolytique dans de l'acide chromique a 6 V pour 1-2 min Presentation des resultats as mentioned in this paper.

TL;DR: In this article, a high resolution autoradiography technique was applied to observe the evolution of sulphur (S) segregation level in high-purity iron doped with carbon, about 30 ppm of S and/or aluminum (Al) and nitrogen (N).

TL;DR: In this article, two types of intermetallic precipitates were found in aluminum alloy 3003 creep tested at 300°C, and high resolution lattice imaging indicated the presence of a number of defect structures in the polycrystalline Al 12 (MnFeCu) 3 Si 2 precipitates.

TL;DR: In this paper, a potentiostatic etching in concentrated orthophosphoric acid at specific potentials is used to reveal the platelet, zonal, and/or grain boundary phases so that they can be viewed by conventional scanning electron microscopy.

TL;DR: In this paper, the methode de determination du rapport is defined: nombre total de particules par unite de volume dans la matrice au nomenclature par unite d'aire sur la replique.

TL;DR: In this paper, structural defects such as stacking faults and overlapping stacking faults, observed in different parts of disc samples, were used as nuclei for the transition from one close-packed structure to the other.

TL;DR: In this article, the microstructure of extruded ingots of Ni3Al containing boron (0.05, 0.09 and 0.12 at%) has been investigated.

TL;DR: In this article, the structure and deformation resistance of quinary Pb-(Al, Mg, Sn, Li) alloys were investigated and a strong trend or correlation existed between the alloy structure and the deformation behavior, both of which depended directly on alloying concentration.