SwePub - search: WFRF:(Easterling K.E.)

Enumeration	Reference	Cover	Find
1.	Arzt, E., et al. (author) Practical applications of hotisostatic Pressing diagrams: Four case studies 1983 In: Metallurgical Transactions. A, Physical Metallurgy and Materials Science. - 0360-2133. ; 14:1, s. 211-221 Journal article (peer-reviewed)abstract The construction of mechanism maps for hot-isostatic pressing is described. Maps are constructed for a number of materials of commercial and scientific interest: a tool steel, a superalloy, Al2O3, and ice. They allow the processes involved in hot-isostatic pressing to be examined, and suggest ways of picking optimum combinations of pressure, temperature, and time to give maximum density.
2.	Ashby, M.F., et al. (author) The fracture and toughness of woods 1985 In: Proceedings of The Royal Society of London. Series A, Mathematical and physical sciences. - : The Royal Society. - 0080-4630. ; 398:1815, s. 261-280 Journal article (peer-reviewed)abstract Crack propagation in various woods has been examined by scanning electron microscopy, and the observations related to measurements of fracture toughness. It is found that the toughness is related in a simple way to the density of the wood, which is explained by a straightforward model. The apparent fracture toughness of wood for cracks that lie normal to the grain is larger, by a factor of about 10, than that for cracks which propagate parallel to the grain. This difference can be explained in terms of the fracture mechanics of very anisotropic solids
3.	Bengtsson, B., et al. (author) Laser hardening of steel 1984 In: Materials Research Society Symposia Proceedings. - Amsterdam : Elsevier. - 0444009019 ; , s. 789-793 Conference paper (peer-reviewed)
4.	Bengtsson, B., et al. (author) Quantitative STEM chemical analysis 1978 In: Scanning electron microscopy. - AMF O'Hare, Ill : Scanning Electron Microscopy, Inc.. ; , s. 655-662 Conference paper (peer-reviewed)
5.	Bengtsson, B., et al. (author) Quantitative STEM microanalysis 1978 In: Scandinavian journal of metallurgy. - 0371-0459 .- 1600-0692. ; 7:2, s. 57-59 Journal article (peer-reviewed)
6.	Easterling, K.E. (author) From powders to super-strength materials via hot isostatic pressing 1982 In: High pressure in research and industry. - Uppsala : Fysikalisk-kemiska inst., Univ. ; , s. 49-52 Conference paper (peer-reviewed)
7.	Easterling, K.E. (author) Metallurgical applications of scanning transmission electron microscopy 1977 In: Journal of Materials Science. - 0022-2461 .- 1573-4803. ; 12:5, s. 857-868 Journal article (peer-reviewed)abstract It is shown that scanning transmission microscopy (STEM) has followed two main lines of development, the pure STEM based upon a field emission electron source in which the emphasis is given to high resolution, and a combined system in which STEM is an attachment to a conventional transmission microscope (TEM+STEM). When used in combination with an energy dispersive X-ray spectrometer, the combined TEM+STEM system is shown to be extremely versatile and possibly the more useful for the applied metallurgist. The high vacuum requirements of pure STEM, however, make this system suitable to be used in conjunction with an Auger spectrometer. Examples of the various microanalysis facilities of STEM are given in the article, including micro-diffraction, rocking-beam channelling patterns, qualitative and quantitative X-ray spectroscopy analysis, particle analysis, and in situ experimentation. The controversial subject of whether thicker specimens can be studied in STEM compared with conventional TEM is also discussed
8.	Easterling, K. E., et al. (author) Metallurgical case studies for engineering students 1973 In: Metals and Materials. - 0026-0940. ; 7:10, s. 452-454 Journal article (peer-reviewed)abstract The course described attempts to help engineering students adapt themselves to solving problems typically encountered in the metals industries
9.	Easterling, K.E., et al. (author) On the growth of martensite in steel 1980 In: Acta Metallurgica. - : Elsevier BV. - 0001-6160. ; 28:9, s. 1229-1234 Journal article (peer-reviewed)abstract Criteria based on minimum energy and maximum stress considerations have been developed for the first stages of growth of martensite in steel. It is shown that the critical size of nucleus at which dislocation-assisted growth can occur is about 25 nm diameter. The mode of growth governing low carbon lath martensite forming on {111} austenite habit planes is found to be fundamentally different from that of plate martensite which forms on irrational habit planes. A mechanism for lath thickening and growth is advanced in which dislocations nucleate at the thickest section of the lath and then follow after the coherent leading edge of the lath to generate ledges. Plate growth on the other hand can occur by the formation of twins which nucleate and thicken laterally behind the coherent leading edge of the plate.
10.	Easterling, K.E., et al. (author) On the mechanics of balsa and other woods 1982 In: Proceedings of The Royal Society of London. Series A, Mathematical and physical sciences. - : The Royal Society. - 0080-4630. ; 383:1784, s. 31-41 Journal article (peer-reviewed)abstract The structure of balsa wood has been characterized by scanning microscopy. The moduli and crushing strengths of the wood, in three orthogonal directions, have been related to the structure and its reponse to load: during deformation the cell walls bend elastically and collapse plastically or by fracture. It is found that the moduli, crushing strengths and anisotropy of balsa and of other wood are determined, in part, by the properties of the cell-wall material, and, in part, by the dimensions and shape of the cells themselves.
11.	Easterling, K. E. (author) Recent developments in quantitative electron microscopy 1977 In: International Metals Review. - : Informa UK Limited. - 0308-4590. ; 22:1, s. 1-24 Journal article (peer-reviewed)abstract Recent developments across the whole field of electron microscopy and associated equipment and techniques are reviewed with particular emphasis on quantitative measurements and analysis. The review is intended to cover a wide field embracing transmission, scanning, and scanning transmission microscopy as well as X-ray spectroscopy, on-line image analysis, and in situ experimentation, with the object of seeing how and to what effect quantitative electron microscopy is serving materials technology.
12.	Easterling, K.E. (author) Scanning-transmission electron-microscopy and microanalysis 1977 In: Scandinavian journal of metallurgy. - 0371-0459 .- 1600-0692. ; 6:1, s. 3-5 Journal article (peer-reviewed)
13.	Easterling, K.E., et al. (author) Some recent developments in powder metallurgy in Sweden 1979 In: Science of Sintering. - 0350-820X. ; 11:spec, s. 105-120 Journal article (peer-reviewed)abstract The authors concentrate on some recent scientific and technological developments in the two main areas of activity in Sweden, i.e. cemented carbides and steel powder metallurgy. They also give a few details of some interesting preliminary work on the hot isostatic pressing of silicon nitride and the development of sintered oxide containers for storing nuclear waste materials
14.	Easterling, K.E., et al. (author) The microstructure and properties of high Tc superconducting oxides 1990 In: Science Progress. - 0036-8504 .- 2047-7163. ; 74:293, s. 69-90 Journal article (peer-reviewed)abstract There has been considerable progress in producing and characterizing high Tc superconductors, but a number of materials science-related problems still exist, before their mechanical and electrical properties meet the requirements of many of the proposed applications. These materials are brittle, ceramic compounds with long unit cells that can be thought of as formed from layers of various oxides are an important common feature. The long unit cell structure leads to anisotropy in their electrical and mechanical properties, including the current carrying capacity or current density Jc. The crystallography and microstructure of the three major families of high Tc superconductors are reviewed and possible solutions to some of the materials problems are presented
15.	Easterling, K.E., et al. (author) The nucleation of martensite in steel 1976 In: Acta Metallurgica. - : Elsevier BV. - 0001-6160. ; 24:4, s. 333-341 Journal article (peer-reviewed)abstract Calculations of the total energy for transforming austenite to martensite in the form of thin ellipsoidal plates, fully coherent with the austenite, show that the process may be spontaneous in the presence of pre-existing dislocations. It is found that dislocations, or groups of dislocations, in the austenite are suitable sites for martensite nucleation in that their strain fields may interact favourably with the strain field associated with the Bain deformation thereby eliminating the energy barrier to nucleation. The driving force for twinning to occur virtually simultaneously with nucleation is large and when this happens energy is released for thickening and growth of the nucleus. It is also found that the strain energy of coherent plates of martensite, whether twinned or untwinned, is a function of their orientation in the austenite, although the lowest strain energy case occur nevertheless over a relatively wide range of orientations
16.	Guo, S.J., et al. (author) Improved single crystal growth in the Bi-Sr-Ca-Cu-O system using a sealed cavity technique 1990 In: Journal of Crystal Growth. - : Elsevier BV. - 0022-0248 .- 1873-5002. ; 100:1-2, s. 303-308 Journal article (peer-reviewed)abstract Bi-Sr-Ca-Cu-O single crystals obtained thus far commonly have a very small thickness in the c-axis because of the weak bonding between two adjacent BiO layers and the high vapour pressure of Bi2O3 at high temperature. To overcome these difficulties a presintered SrCaCu4O6 was used to seal the Bi-Sr-Ca-Cu-O melt from which the single crystals grew during slow cooling. In the SrCaCu4O6 sealed cavity the Bi loss through vaporization was prevented and Sr and Ca were enriched in the superconducting crystals. The resulting single crystals have a dimension of up to 3.0×1.5×0.7 mm3, which is two orders of magnitude thicker than those grown from alkali chloride flux. The composition of the crystals is Bi2.2Sr1.8Ca0.75Cu1.8Ox and they possess a zero resistance at temperature above liquid nitrogen
17.	Helle, A.S., et al. (author) Hot isostatic pressing diagrams : new developments 1985 In: Acta Metallurgica. - : Elsevier BV. - 0001-6160. ; 33:12, s. 2163-2174 Journal article (peer-reviewed)abstract The equation and procedures for constructing hot-isostatic pressing diagrams are simplified and clarified. In earlier work, three classes of mechanism were modelled: plastic yielding, power-law creep and diffusional densification. In this paper two further mechanisms are added: diffusional deformations of particles when the grain size is smaller than the particle size, and separation of pores from boundaries when grain growth occurs. Application of HIP diagrams to tool steels, alumina and copper are discussed
18.	Li, Wen-Bin, et al. (author) Instantaneous and residual stresses developed in hot isostatic pressing of metals and ceramics 1991 In: Metallurgical and Materials Transactions. A. - 1073-5623 .- 1543-1940. ; 22:5, s. 1071-1078 Journal article (peer-reviewed)abstract Under many conditions, hot isostatic pressing (HIP) of metallic or ceramic porous preforms occurs by the densification of a shell at the surface of the preform, which then thickens until the whole sample is fully densified. The development of such a dense shell reduces the effective pressure acting to densify the remaining porosity. Furthermore, this pressure difference can lead to anisotropic creep of the shell, and this may be a contributary cause of shape change of samples during HIP. The stresses occurring during cooling of the sample and the residual stresses are calculated as a function of all of the various material and pressing parameters. It is found that, in many cases, the cooling stresses which are tensile at the surface may well be large enough to cause cracking in ceramic samples
19.	Li, Wen-Bin, et al. (author) On densification and shape change during hot isostatic pressing 1987 In: Acta Metallurgica. - Cambridge : Elsevier BV. - 0001-6160. ; 35:12, s. 2831-2842 Journal article (peer-reviewed)abstract When the temperature of a powder compact is raised, heat diffuses inwards from the surface. If the compact is under pressure (as it is during HIPing), the surface layers start to densify, increasing the local thermal conductivity. Under certain conditions a densification front then propagates into the powder, and this leads to changes of shape of the compact, which is no longer identical to the preform shape. The conditions which lead to non-uniform densification are analysed and the consequences are discussed, and compared with experiments
20.	Li, Wen-Bin, et al. (author) On the Zener drag pressure by cubic shaped particles 1988 In: Strength of metals and alloys. - Amsterdam : Elsevier. - 0080348041 ; , s. 1345-1350 Conference paper (peer-reviewed)abstract All models of the Zener drag effect, in which precipitate particles hinder the movement of migrating grain boundaries, are based on spherical or ellipsoidal particles. Zener drag by cubic shaped particles is modelled. It is shown that cubic particles are generally more effective than spherical particles in holding up grain growth, and that coherent particles are better in this respect that incoherent particles
21.	Li, Wen-Bin, et al. (author) Residual stresses in laser transformation hardened steel 1986 In: Surface Engineering. - : Informa UK Limited. - 0267-0844 .- 1743-2944. ; 2:1, s. 43-48 Journal article (peer-reviewed)abstract A simple analytical solution is developed for calculating the residual stresses which occur as a result of the laser transformation hardening of steel surfaces. The solution is based mainly on taking account of the dilatation resulting from the martensitic transformation and allows the influence of the many and varied parameters involved in laser transformation hardening (beam size and intensity, material properties, composition, etc.) to be readily assessed. Satisfactory agreement between the theoretical predictions and reported experimental measurements of residual stress is obtained
22.	Loberg, Bengt, et al. (author) Improvement in toughness of welded constructional steels through titanium additions 1980 In: Philosophical Transactions of the Royal Society of London. Series A. - : The Royal Society. - 0080-4614 .- 2054-0272. ; 295:1413, s. 306- Journal article (peer-reviewed)abstract Summary form only given. The authors present an interim report on the effect of various alloying additions in the weld deposit and base material on the precipitate dispersion and stability, the microstructure and toughness of microalloyed constructional steels, in both the as-welded as well as welded and stress-relieved conditions. Materials investigated include welded AlTi, AlTiV, AlTiNb and AlV steels with the use of electrodes either with or without Mo additions
23.	Navara, E., et al. (author) Martensite formation in the haz of welded microalloyed steels 1982 In: Scandinavian journal of metallurgy. - 0371-0459 .- 1600-0692. ; 11:4, s. 169-172 Journal article (peer-reviewed)abstract THE WELDING OF FINE GRAINED MICROALLOYED STEELS CAN BRING ABOUT CONSIDERABLE GRAIN GROWTH IN THE HEAT AFFECTED ZONE (HAZ) AND THIS IN TURN INCREASES THE POSSIBILITY OF MARTENSITE FORMATION. WELDING DIAGRAMS HAVE RECENTLY BEEN DEVELOPED FORPREDICTING THE AMOUNT OF GRAIN GROWTH IN THE HAZ OF VARIOUSSTEELS. THE OBJECT OF THE PRESENT WORK WAS TO STUDY THE AMOUNT OF MARTENSITE AS A FUNCTION OF GRAIN SIZE IN THE HAZ, AND TO SUPERIMPOSE THESE FIGURES ON THE WELDING DIAGRAM OF A NB-STEEL.
24.	Navara, E., et al. (author) Surface treatment of steel by laser transformation hardening 1984 In: Heat treatment, Shanghai '83. - London : Minerals, Metals & Materials Society. - 0904357651 ; , s. 40-44 Conference paper (peer-reviewed)
25.	Niska, John, et al. (author) Effect of oxygen loss on densification when hot isostatic pressing YBa2Cu3O7-δ 1989 In: Journal of The American Ceramic Society. - : Wiley. - 0002-7820 .- 1551-2916. ; 72:8, s. 1508-1510 Journal article (peer-reviewed)abstract Hot isostatic pressing of the high-Tc superconductor YBa2Cu3O7-δ can lead to loss of oxygen and transformation of the material from the high-Tc orthorhombic phase to the nonsuperconducting tetragonal phase. It is shown that glass encapsulation helps retain the orthorhombic structure, whereas steel encapsulation resulted in formation of the tetragonal phase. Reasons for this phenomenon are discussed. The equilibrium oxygen gas pressure for the oxygen decomposition reaction in YBa2Cu3O7, however, prevents full densification of this material in glass when employing hot isostatic pressing conditions of 200 MPa and 845°C.
26.	Niska, John, et al. (author) Thermal expansivity of HIP synthesized YBa2Cu4O8 1991 In: Physica Scripta. - : IOP Publishing. - 0031-8949 .- 1402-4896. ; 44:1, s. 93-94 Journal article (peer-reviewed)abstract The thermal expansion coefficient of a sample of the YBa2Cu4O8 phase superconductor was measured using a low temperature X-ray diffractometer. The thermal expansivity was found to be highly anisotropic. The average coefficient of thermal expansion over the temperature range of 150 to 450 K was approximately equal for the a and b axes at 9×10-6/°C, vs a coefficient of about 15×10-6/°C for the c axis. This would indicate that the bonding is weaker along the c-axis than in the ab-plane and that the specific heat of single crystals of the high Tc superconductors can depend on their geometry. The low thermal expansivity in the ab-plane relative to typical metal conductors as copper and silver could lead to compressive stresses in the superconductor when cooling a composite metal-superconductor wire having good alignment of the ab-plane along the wire axis
27.	Porter, D.A., et al. (author) Dynamic studies of the deformation and fracture of pearlite using 200 kV SEM 1978 In: Electron microscopy 1978. - Toronto : Microsopical Soc. of Canada. - 0920622062 ; , s. 578-579 Conference paper (peer-reviewed)abstract Summary form only given, as follows. The influence of interlamellar spacing on the mechanics of deformation was studied and the materials examined ranged from coarse pearlite, with a mean interlamellar spacing λ~0.4 μm, to fine pearlite with λ~0.1 μm. The problems of ex post facto reasoning regarding the modes of deformation were avoided by continuously following deformation with the TV monitor and recording high resolution slow scan micrographs from the same area both before and after straining. The results of this investigation have shown that there are large differences in the deformation and fracture mechanisms between coarse and fine pearlites, especially when the cementite lamellae are aligned close to the tensile axis
28.	Porter, D.A., et al. (author) Dynamic studies of the tensile deformation and fracture of pearlite 1978 In: Acta Metallurgica. - : Elsevier BV. - 0001-6160. ; 26:9, s. 1405-1422 Journal article (peer-reviewed)abstract High resolution 200 kV scanning electron microscopy has been used to study in situ the tensile deformation and fracture of a range of pearlites, from relatively coarse mean interlamellar spacing of about 400 nm, to very fine mean spacing of about 90 nm. It was found that there were considerable differences in the tensile deformation behaviour between fine and coarse pearlites. A model is proposed to account for the differences based upon a combination of pile-up and fibre loading stresses, in which the operating deformation mode is largely determined by which type of mechanism is dominant
29.	Porter, D.A., et al. (author) Dynamic studies of the tensile deformation and fracture of pearlite using high-resolution 200-KV sem 1978 In: Scandinavian journal of metallurgy. - 0371-0459 .- 1600-0692. ; 7:2, s. 55-56 Journal article (other academic/artistic)
30.	Ringer, S.P., et al. (author) Liquid film simulation of Zener grain boundary pinning by second phase particles 1991 In: Materials Science and Technology. - : Informa UK Limited. - 0267-0836 .- 1743-2847. ; 7:3, s. 193-200 Journal article (peer-reviewed)abstract The geometry of the interaction of second phase particles with migrating grain boundaries has been studied using a liquid film simulation. The geometries observed show that the perimeter of intersection between boundary and particle can be complex, often not lying in a single plane through the particle. The curvature of the boundary when in contact with the particle is also complex, sometimes displaying double curvature and often of opposite sign. These observations have been used to modify previous calculations quantifying the grain boundary pinning effect. Measurements from the photographs of these interactions have been applied to a force equilibrium approach for calculating the pinning force and these results are found to be in good agreement with values obtained using an energy analysis based on grain boundary shape change
31.	Ringer, S.P., et al. (author) On the interaction and pinning of grain boundaries by cubic shaped precipitate particles 1989 In: Acta Metallurgica. - : Elsevier BV. - 0001-6160. ; 37:3, s. 831-841 Journal article (peer-reviewed)abstract Previous models of the Zener pinning of migrating grain boundaries by precipitates are all based on spherical or ellipsoidal particles. In this work, theoretical and experimental studies are made of pinning by stable, cubic-shaped particles. It is shown that cubic-shaped particles are generally more effective than spherical particles in holding up grain growth. Pinning is also more effective if particles are fully coherent. Transmission electron microscopy is used to study actual grain boundary/particle interactions in a Ti-microalloyed steel in which the coherent precipitate is a stable, cubic-shaped titanium nitride compound. The interactions observed are discussed in the light of the models developed
32.	Sotkovszki, P., et al. (author) Secondary ion analysis of segregation in welded steels 1979 In: Metal Science. - : Maney Publishing. - 0306-3453. ; 13:10, s. 597-601 Journal article (peer-reviewed)abstract The role of weld defects, such as root cracks, or cold cracking in helping to initiate fatigue failure or reducing the impact toughness of welded constructions is now fairly well established. In the case of cold cracking, it is now standard procedure to use the basic (low-hydrogen) electrodes when welding high-strength micro alloyed fine grained or quenched and tempered steels. However, it has to be acknowledged that the mechanism of cold cracking and its relation to the dispersion of inclusions or the amount of hydrogen in steels is not well understood. It has been established that cold cracking may arise in welds containing martensite due evidently to the fact that hydrogen has a lower solubility in martensite than ferrite. However, whether the expelled hydrogen then congregates at the martensite/ferrite phase boundary or elsewhere has not been clarified. It was thus the object of the present work to consider some of the metallurgical consequences of using basic or rutile electrodes when welding high-strength steels, with particular reference to the segregation of the various alloying elements around inclusions. For this purpose the relatively new technique of secondary ion analysis was employed in conjunction with light and electron microscopy. The unique feature of secondary ion analysis is that hydrogen can be detected even when present in relatively small amounts.
33.	Strid, J., et al. (author) On the chemistry and stability of complex carbides and nitrides in microalloyed steels 1985 In: Acta Metallurgica. - : Elsevier BV. - 0001-6160. ; 33:11, s. 2057-2074 Journal article (peer-reviewed)abstract Light optical and elctron microscopy, and quantitative (STEM-EDX) micro-analysis are employed to characterize a number of different Ti-micro-alloyed steels, containing various alloying additions including high and low levels of nitrogen, and a Nb-steel is used as a comparison. Weld thermal cycling treatments substantially change particle compositions compared to the as-received (rolled or normalized) conditions, and even the energy input of the welding process is of importance in this respect. As a general rule, TiN-containing steels provide for good grain growth control during weld cycling, although the presence of additional alloying elements in the particles may affect particle stability in a complicated way. It is shown that equilibrium thermodynamics can be used to make reasonable predictions of particle compositions provided the prior heat treatment is such to allow the particles to remain near their equilibrium condition
34.	Strid, J., et al. (author) On the strength, deformation and fracture of directional eutectic alloys tested in uniaxial tension 1982 In: Scandinavian journal of metallurgy. - 0371-0459 .- 1600-0692. ; 11:6, s. 295-298 Journal article (peer-reviewed)abstract Three dimensional eutectic alloys, Al-Cu, Al-Fe and Ag-Cu, are investigated using SEM and TEM to characterize the microstructures, and in-situ uniaxial tensile testing in the high resolution SEM stage of a STEM to study the detailed deformation and fracture mechanisms. It is found that if predictions of the strength and fracture behaviour of these alloys are to be reliable, the effect of both the interlamellar spacings and the many different types of eutectic inhomogeneities must be accounted for.
35.	Strömgren, M., et al. (author) The effect of interparticle contact area on the strength of cold-pressed aluminium powder compacts 1973 In: Powder Metallurgy. - : Informa UK Limited. - 0032-5899 .- 1743-2901. ; 16:32, s. 155-165 Journal article (peer-reviewed)abstract Measurements of the tensile strength of spherical cold-pressed aluminium powder, pressed to various densities up to the theoretical maximum, have shown that compaction is a two-stage process. At some high, intermediate pressure, interparticle sliding occurs in a way that does not itself increase densification but makes it easier for further deformation to occur. It is likely that the pressure at which this sliding takes place is dependent on the work-hardening rate of the powder as well as the powder size and morphology. In any case, it is shown to be important to the densification and strength reached by the compact. It is concluded that the strength of a green compact is dependent upon the interparticle metallic contacts made during compaction. However, the green strength is well below that of wrought aluminium, probably due to the presence of broken-up oxides, which act as stress-concentrators at the interparticle boundaries.
36.	Vishnu, P. Ravi, et al. (author) A model based investigation into the promise of using pulsed GRAW for weld repairs 1993 In: International trends in welding science and technology. - Materials Park, Ohio : ASM International. - 0871704765 ; , s. 399-404 Conference paper (peer-reviewed)abstract Pulsed GTAW is shown to have certain advantages which can make it competitive to other "temper-bead" procedures developed in the past for in situ weld repairs. Low pulse frequencies and low welding speeds are shown to be required for obtaining the necessary degree of microstructural refinement for such applications. This conclusion is drawn from a model based analysis experimental data from pulsed GTRAW weldments on a AT steel. Relating the model to the experimental results was possible only after the heat flow model was calibrated with the experimental data obtained from a metallograhic characterisation of the pulsed welds and partially from dilatometric measurements during thermal cycle simulation. This phenomenological or "inverse modelling" procedure of estimating the physical constants in the heat flow model was made easier and more "well-conditioned" because transient information about the thermal cycles and phase transformations could be inferred from the pulsed weldments and the weld simulation trials.
37.	Vishnu, P. Ravi, et al. (author) Phenomenological modelling of heat flow and microstructural changes in pulsed GTA [TIG] welds in a quenched and tempered steel 1993 In: Mathematical modelling of weld phenomena. - London : Institute of Materials. - 0901716162 ; , s. 241-300 Book chapter (other academic/artistic)abstract mathematical model is presented for determining the thermal cycles in pulsed TIG welds in a quenched and tempered microalloyed steel (0.15%C, 1.4%Mn, 0.026%Nb, 0.061%V, 0.064%Al, 0.083%Mo, 12 mm thickness). The heat flow model is also used to characterise the phase transformations. The modelling of the kinetics of phase transformations using the dilatometric plots obtained during the simulation trials is also described. Bead-on-plate welds were made without filler wire. The application of pulsed welding to weld repairs is discussed
38.	Åström, H., et al. (author) Hot cracking and micro-segregation in 18-1 0 stainless steel welds 1976 In: Metal Science. - : Maney Publishing. - 0306-3453. ; 10:7, s. 225-234 Journal article (peer-reviewed)abstract Advanced quantitative chemical and image analysis techniques based on scanning and scanning-transmission electron miCroscopy have been used to study hot cracking and micro-segregation in an 18%Cr-10%Ni weld metal. It is found that the main cause of hot cracking is sulphur segregation. In fully austenitic welds, manganese remains in solution and when the last of the S-rich 'melt solidifies Mn is simply not available to break up the sulphide films. The present practice of substantially increasing the amount of Mn in austenitic welds, or adding cerium, would thus seem to be justified. Phosphorus also aggravates the problem of hot cracking, but fortunately it does not appear to segregate so markedly as sulphur, being much more soluble in austenite. If the weld metal is so alloyed that solidification to the two-phase austenite plus ferrite occurs, hot cracking does not occur. The two main reasons are concluded to be: (1) manganese is less soluble in ferrite than austenite and a sufficient quantity of Mn is evidently released to combine with S and form inclusions; (2) the structural refinement of two-phase structures, compared to the single-phase austenite, results in a more even distribution of Sand P throughout the weld metal, and marked segregation is thus avoided.

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