Showing papers on "Equiaxed crystals published in 1988"
TL;DR: In this article, a spray cast strip of AISI 1026 and M2 has been produced by the Osprey™ process under controlled conditions of deposition, and surface condition, microstructure, and extent of porosity in the strip were characterized as a function of distance from top and bottom surfaces.
Abstract: Spray cast strip of AISI 1026 and M2 has been produced by the Osprey™ process under controlled conditions of deposition. Droplet flight distance was varied over the range 325 to 475 mm and strip was spray cast onto either planar or roller substrates of copper and steel. Substrate surface speed was in the range of 0.02 to 1 m/s, which produced strip of 0.025 to 0.0007 m thickness, respectively, with a width of 0.1 m. Surface condition, microstructure, and extent of porosity in the strip were characterized as a function of distance from top and bottom surfaces. The microstructure of the strip is comprised of three regions —a ‘chill zone’ at the bottom surface consisting of fine grains of ferrite and pearlite with numerous pores; a middle region containing equiaxed or columnar grains, Widmanstatten plates, and fine pores; and a top region made up of equiaxed grains comprising Widmanstatten plates and a few pores. Process variables of primary importance with respect to microstructural integrity and surface condition of the strip are substrate velocity, the surface condition of the substrate, flight distance, and the uniformity of droplet flux in the spray cone. Flight distance determines the amount of cooling of the droplets by the atomizing gas and, therefore, the average temperature of the spray incident on the substrate. Microstructure is determined by convective cooling of the spray, and, to a lesser extent, by the substrate velocity and temperature. The processing conditions required to spray cast strip with a homogeneous microstructure and uniform thickness/surface condition have been established.
90 citations
TL;DR: In this article, it was shown that thin single crystals and large bulk single crystals grow in films of vinylidene fluoride and trifluoroethylene copolymers when they are annealed at temperatures between the Curie point and melting point.
Abstract: Thick lamellar single crystals and large bulk single crystals are found to grow in films of vinylidene fluoride and trifluoroethylene copolymers when they are annealed at temperatures between the Curie point and melting point. The morphologies of these crystals are studied using SEM, TEM, and X-ray diffraction. The lamellar crystals are thick (0.1 µm) enough to be characterized as extended chain crystals. They are stacked together with their planes perpendicular to the film surface. The bulk single crystals exhibit various crystal habits with the maximum size 12 × 10 × 10 µm3. They are developed on the lamellar crystals from which the constituent molecules seem to be supplied. The growth of the crystals is discussed on the basis of the diffusive displacement of the molecules along the chain axis which becomes violent above the Curie temperature.
54 citations
TL;DR: In this article, a cube having edges of 52·1 mm was cut from a slowly cooled β-brass ingot which had equiaxed grains and the distributions of sizes and shapes of grain sections on the faces of the cube were determined.
Abstract: A study was undertaken to define better the concept of the statistical grain. A cube having edges of 52·1 mm was cut from a slowly cooled β-brass ingot which had equiaxed grains. The distributions of sizes and shapes of grain sections on the faces of the cube were determined. The grains were then separated in a solution of mercurous nitrate and nitric acid. Observations were made of the relationship between grain diameter and the number and shapes of faces. For the 941 separated whole grains, the frequency of distribution of grain diameters obeyed the log–normal law. A plane distribution curve was derived for the statistical grain which enables spatial distributions to be calculated from measurements made on a plane section.MST/825
47 citations
TL;DR: In this article, the effects of matrix composition, reinforcing phase, and thermal mechanical processing on properties have been studied using optical and various electron microscopy and mechanical and physical property measurement techniques to characterize the alloys.
Abstract: The advantages of reinforcing metals with ceramic particles to produce metal matrix composites are well known. The behavior of discontinuously reinforced intermetallic compounds, however, has not been extensively studied. Martin Marietta Laboratories has produced a new generation of discontinuously reinforced titanium aluminide composites using a proprietary casting process known as XD™ technology. These new materials possess enhanced properties at room and elevated temperatures and may be cast, extruded, or forged. The effects of matrix composition, reinforcing phase, and thermal mechanical processing on properties have been studied using optical and various electron microscopy and mechanical and physical property measurement techniques to characterize the alloys. To date, most work has been done on a two-phased lamellar Ti-45 a/o Al alloy reinforced with TiB2 ceramic having an equiaxed morphology. Data on temperature dependence of the dynamic Young’s modulus, coefficient of thermal expansion, deformation and fracture behavior, and microstructure are presented.
42 citations
Patent•
20 Oct 1988TL;DR: In this paper, the authors present a method and apparatus for controlling radial solidification in cast turbine wheel or nozzle assembly so as to produce an equiaxed fine grain structure in a hub portion (24) and a directionally solidified grain structure (21) by means of adjustable heat shields (40, 50) and heating elements (30, 70) disposed above and below the mold.
Abstract: Method and apparatus for controlling radial solidification in cast turbine wheel or nozzle assembly so as to produce an equiaxed fine grain structure in a hub portion (24) and a directionally solidified grain structure in an integral blade portion (21) by means of adjustable heat shields (40, 50) and heating elements (30, 70) disposed above and below the mold.
33 citations
TL;DR: In this paper, the effect of variations in wheel speed and melt superheat on ribbon dimensions and microstructures of Ag-19wt.%Cu melt spun under high vacuum conditions were examined.
19 citations
TL;DR: In this article, the structure and compositions of single-phase and two-phase La2O3-doped Y 2O3 materials fabricated by the transient solid second-phase sintering were defined.
Abstract: Transmission electron microscopic analyses defined the structures and compositions in single-phase and two-phase La2O3-doped Y2O3 materials fabricated by the transient solid second-phase sintering. The composition in single-phase, 10-mol%-La2O3-doped, sintered and annealed samples was found to be uniform, indicating that diffusivity was sufficiently high for homogenization in the single-phase field. Two-phase, 16-mol%-La2O3-doped, sintered and annealed samples showed two morphologies: (1) intragranular, lath-like, monoclinic second-phase particles (twinned and untwinned) and (2) equiaxed cubic matrix. The second-phase particles were identified as the monoclinic phase derived from the high-temperature hexagonal phase through a rapid phase transition. A short, high-temperature anneal (2200°C for 1 min) of 9 mol% La2O3-Y2O3 composition was found to retain the hexagonal phase. Microchemical analyses of the phases suggested adjustments to the Y2O3-La2O3 phase diagram. Observation of the interactions of the intragranular second-phase particles with crack propagation indicated crack deflection as one of the mechanisms responsible for toughening (1.5 vs 0.9 MPa · m1/2).
18 citations
TL;DR: A series of critical experiments was performed on single crystal CMSX-3 and equiaxed grain Mar-M246 specimens to identify the mechanisms responsible for the degradation in stress-rupture properties of 0.020 in. thick miniflats machined from airfoils as mentioned in this paper.
Abstract: A series of critical experiments was performed on single crystal CMSX-3 and equiaxed grain Mar-M246 specimens to identify the mechanisms responsible for the degradation in stress-rupture properties of 0.020 in. thick mini-flats machined from airfoils compared with 0.250 in. diameter standard test bars. Both materials exhibited approximately a factor of 3X life degradation at a stress level of 20,000 lb/in.2, when uncoated airfoil mini-flats were tested in air. To determine the influence of specimen geometry on test results, a series of tests was conducted on CMSX-3 alloy using 0.020 in. thick miniflats and 0.020 in. wall-thickness cylindrical hollow specimens. Both types of specimens were machined from 5/8 in. diameter bars. The results obtained indicated no noticeable difference in stress-rupture lives, suggesting that, in this material, specimen geometry does not influence the test results. The next series of tests was conducted using aluminide coated CMSX-3 airfoil mini-flats tested in air and uncoated airfoil mini-flats tested in high purity argon. The stress-rupture lives obtained were equivalent to those obtained on 0.250 in. diameter baseline specimens, suggesting that, in this material, the life degradation observed in airfoil mini-flats is primarily due to environmental effects. The last series of tests was conducted using aluminide coated equiaxed grain Mar-M246 airfoil mini-flats. No improvement in stress-rupture Superalloys 1988 Edited by S. Reichman, D.N. Duhl, G. Maurer, S. Antolovich and C. Lund The Metallurgical Society, 1988 653 lives was obtained compared with uncoated airfoil mini-flats tested in air, suggesting that the primary life degradation mechanism in this material is related to the behavior of grain boundaries in thin sections.
17 citations
TL;DR: In this paper, changes in the texture and grain shape of an Al-Li alloy sheet superplastically deformation into the shape of a cone have been measured as a function of strain.
Abstract: Changes in the texture and grain shape of an Al–Li alloy sheet superplastically
deformed into the shape of a cone have been measured as a function of strain. The
starting microstructure was characterised by strong {110}〈112〉 and {123}〈634〉
orientations, together with a number of minor orientations, and an elongated grain
shape. Increases and decreases in the intensities of the individual orientations
occurred at low values of strain (<0.5) as the elongated grains became equiaxed.
Once all the grains were equiaxed, however, there was a continuous decrease in the
intensities of all orientations, except for those of some minor orientations which
remained essentially constant. The results are explained in terms of slip occurring in
the early stages of deformation, because elongated grains will experience difficulty in
sliding and rotating, but becoming negligible when grains are equiaxed and are free
to slide and rotate. There was some evidence of dynamic recrystallisation but only
whilst slip occurred.
11 citations
TL;DR: In this paper, a PC-based single specimen unloading technique was described in Part I of the paper, where the applicability of the technique was demonstrated using two different materials: a nuclear grade pressure vessel material, A533B Class I steel and an α-β titanium alloy, CORONA-5.
10 citations
TL;DR: In this article, a titanium alloy of nominal composition Ti-6·5Al-3·3Mo-1·6Zr (wt-%) for three strain rates (1·04 × 10−3, 2·1 × 10-3, and 4·2 × 10 −3s−1) and in the temperature range 1123-1223 K for microstructures obtained by different processing schedules.
Abstract: Superplasticity in terms of total tensile elongation was studied in a titanium alloy of nominal composition Ti–6·5Al–3·3Mo–1·6Zr (wt-%) for three strain rates (1·04 × 10−3, 2·1 × 10−3, and 4·2 × 10−3s−1) and in the temperature range 1123–1223 K for microstructures obtained by different processing schedules. Fine equiaxed microstructure with a low aspect ratio of 1·15 was accomplished in this alloy by combining two types of deformation. While the first step consists of heavy deformations for refining and intermixing the phases, a second step, consisting of light homogeneous reductions in several stages, was necessary to remove the banding that developed during the first step. The resulting microstructure underwent enormous tensile elongation (1700–1725%), even under relatively high strain rates (1·04 × 10−3 and 2·1 × 10−3s−1), making this alloy most suitable for commercial superplastic forming. The present investigation also revealed that the usual sheet rolling practice of heavy reductions to refi...
TL;DR: In this article, the bend strength of polycrystalline H3O+β-δ-ε β-ε/β-ε Al2O3 and ZrO2 was > 200 MPa.
TL;DR: In this article, the effect of temperature, initial strain rate and cold rolling on the superplasticity of duplex stainless steel was investigated, and the results were compared with the same type of steel manufactured by the conventional process.
Abstract: Characteristics of superplasticity in a duplex stainless steel produced by a direct strip casting (DSC) technique have been studied. The thickness of a strip is 1.2mm. The effect of temperature, initial strain rate and cold rolling is investigated. The results are compared with the same type of steel manufactured by the conventional process. An as-cast strip shows superplasticity at 1273K. The superplasticity is enhanced by cold reduction through recrystallization and sigma phase precipitation during heating. An as-cast strip followed by 50% cold reduction without annealing is superplastic at 1173K or higher temperatures. The obtained maximum elongation of cold rolled strip is 1029% when strained for a rate of 8.33×10-4s-1 at 1273K. The mechanism of superplasticity in these materials is discussed. The precipitation of fine austenite phases occurs during heating, and the straining at a high temperature causes grain rotation so that the microstructure is equiaxed. Rapid cooling by a pair of drums makes it possible to reduce compositional segregation. The effect of cold reduction is remarkable by acceleration of precipitation of both sigma phase and austenite phase to supply large grain or inter phase boundary area. The superplastic ductility by the sigma phase is enhanced at a relatively higher strain rate range than by austenite phase. This may be explained by that sigma phase precipitation occurs faster than recrystallization of austenite phases at heating and straining stage.
Patent•
25 Mar 1988
TL;DR: In this article, the authors describe a material (504), having adjacent regions of differing strength and ductility, that has been formed by rapidly deforming a suitable base metal (501) having a banded structure, such as illustartively a previously cold worked low carbon steel alloy, in order to generate a high rate of change in the internal energy of the base metal.
Abstract: The invention relates to a material (504), having adjacent regions of differing strength and ductility, that has been formed by rapidly deforming a suitable base metal (501) having a banded structure, such as illustartively a previously cold worked low carbon steel alloy, in order to generate a high rate of change in the internal energy of the base metal. This energy change depressed the transformation temperatures of the base metal and induced an allotropic phase transformation to occur therein. Specifically, prior to being deformed, the base metal is maintained at a fairly low temperature, e.g. at or near room temperature. The tooling, preferably rolls, that is used to provide the deformation is maintained at a modestly elevated temperature. Subsequent rapid deformation of the base metal causes an extremely high heating rate to occur at each surface thereof which, in turn, depresses the upper and lower on heating transformation temperatures at surface regions of the base metal and thereby causes the banded structure of the metal situated in these surface regions to transform into equiaxed grains. If the heating rate is insufficient to raise the temperature of the core of the base metal, which contains banded grains, to a level that causes metal in the core to transform, then the core will retain its banded cold worked structure. Consequently, the transformed surface regions (510, 510') will possess an equiaxed grain structure which provides increased ductility; while the core (511) of the material retains its banded (deformed) grain structure which provides high strength. Hence, the surfaces (512, 512') of the material become soft and ductile while the core possesses considerably higher amounts of hardness, yield and tensile strength than either surface. This material advantageously exhibits both good workability and relatively high strength. Alternatively, if the deformation rate is increased, such as by using small diameter rolls, in order to increase the bulk heating rate of the base metal and the appropriate thickness of the base metal has been chosen, then the entire base metal transforms into equiaxed grains. In this case, the resulting material (404) possesses a ductility and hence workability similar to that of a fully annealed structure.
Patent•
22 Mar 1988
TL;DR: In this article, the authors describe a method for forming a material with high strength and good workability by rapidly deforming a suitable base metal having a banded structure, such as illustratively a previously cold worked plain low carbon steel alloy, in order to generate a high rate of change in its internal energy which depresses the transformation temperatures of the base metal and thereby induces an allotropic phase transformation to occur therein.
Abstract: The invention relates to apparatus and accompanying methods for use therein for forming a material (504), which has high strength and good workability, by rapidly deforming a suitable base metal (501) having a banded structure, such as illustratively a previously cold worked plain low carbon steel alloy, in order to generate a high rate of change in its internal energy which depresses the transformation temperatures of the base metal and thereby induces an allotropic phase transformation to occur therein. This rapid deformation can be produced through rolling, extrusion or forging and causes an extremely high heating rate to occur at each surface of the base metal. Prior to being deformed, the base metal is maintained at a fairly low temperature, e.g. at or near room temperature. The tooling, preferably rolls, that is used to provide the deformation is maintained at a modestly elevated temperature. Subsequent rapid deformation of the base metal causes an extremely high heating rate to occur at each surface thereof which, in turn, depresses the upper and lower on heating transformation temperatures at surface regions of the base metal and thereby causes the banded structure of the metal situated in these surface regions to transform into equiaxed grains. If the heating rate is insufficient to raise the temperature of the core of the base metal, which contains banded grains, to a level that causes metal in the core to transform, then the core will retain its banded cold worked structure. Consequently, the transformed surface regions (510, 510') will possess an equiaxed grain structure which provides increased ductility; while the core (511) of the material retains its banded (deformed) grain structure which provides high strength. Hence, the surfaces (512, 512') of the material become soft and ductile while the core possesses considerably higher amounts of hardness, yield and tensile strength than either surface. This material advantageously exhibits both good workability and relatively high strength. Alternatively, if the deformation rate is increased, such as by using small diameter rolls, in order to increase the bulk heating rate of the base metal and the appropriate thickness of the base metal has been chosen, then the entire base metal transforms into equiaxed grains. In this case, the resulting material (404) possesses a ductility and hence workability similar to that of a fully annealed structure.
TL;DR: Two schemes have been proposed to explain the observed Nb3Sn layer morphology in bronze-processed superconducting wire as mentioned in this paper, where columnar grains develop very early during layer growth and retain approximately constant length.
Abstract: Two schemes have been proposed to explain the observed Nb3Sn layer morphology in bronze-processed superconducting wire. One scheme attributes the morphology to the competition between nucleation and growth of Nb3Sn grains at the niobium interface while the other ascribes it to a breakup of the columnar grains. Microstructural observations show that the latter scheme operates. Columnar grains develop very early during layer growth. With subsequent layer growth they retain approximately constant length. Since the layer continues to grow this requires that the columnar grains formed earlier in the reaction break-up. This process is responsible for the observed equiaxed grain morphology. The few dislocations observed in the columnar or equiaxed grain regions are present to accommodate the crystallographic mismatch between grains. Recrystallization is not indicated since fine grains are not observed. The specific mechanism for the columnar grain break-up remains unclear; however, two classes of processes have been excluded, polygonization and recrystallization.
Patent•
06 Sep 1988
TL;DR: In this paper, an Al-Mg-Zn alloy with a specific composition and preliminary heat treatment is applied to the above under specific conditions, and growing equiaxed crystalline grains.
Abstract: PURPOSE: To improve surface characteristics, stress corrosion cracking resistance, etc., after forging, heat treatment, and anodizing treatment by casting an Al-Mg- Zn alloy with a specific composition, applying preliminary heat treatment to the above under specific conditions, and growing equiaxed crystalline grains. CONSTITUTION: A bar having a composition consisting of, by weight, 0.40-2.50% Mg, 3.5-6.5% N, 0.2-0.8% Mn, 0.03-0.25% Zr, ≤0.30% Cu, ≤0.25% Cr, 0.01-0.20% Ti and/or 0.002-0.050% B, and the balance Al with inevitable impurities is cast. Preliminary heat treatment is applied to the above cast bar at 400-550°C for 1-24hr, by which the structure is grown into equiaxed crystalline grains of 50μm-5mm grain size extensively from the surface layer part to the central part. By this method, the cast Al-alloy bar in which the formation of coarse recrystallized grains is prevented at the time of hot forging and heat treatment and which has superior surface characteristics after anodizing treatment can be obtained. COPYRIGHT: (C)1990,JPO&Japio
TL;DR: A series of electromagnetic stirring experiments was carried out in this article to specify the most effective factor on the generation of equiaxed zone, and it has been shown that the volume of the evaporation zone has a good correlation with the wall shear stress calculated on the basis of the kW model of turbulence.
Abstract: A series of electromagnetic stirring experiment was carried out in order to specify the most effective factor on generation of equiaxed zone. It has been shown that the volume of equiaxed zone has a good correlation with the wall shear stress calculated on the basis of the kW model of turbulence. The correlation is consistent both with the remelting theory of dendrite arms and the mechanical fracture theory of dendrite arms.
Patent•
02 Jun 1988
TL;DR: In this paper, a low-temp steel sheet having excellent low-tope toughness, and particularly the toughness in the central part of the sheet thickness by subjecting a slab having a specific compsn and equiaxed crystal rate to casting, then to hot rolling and heat treatment is presented.
Abstract: PURPOSE:To permit production of an Ni-contg steel sheet having excellent low temp toughness, and particularly the toughness in the central part of the sheet thickness by subjecting a slab having a specific compsn and equiaxed crystal rate to casting, then to hot rolling and heat treatment CONSTITUTION:A molten steel consisting, by weight %, <=02% C, 001-04% Si, 03-20% Mn, <=0004% P, 30-10% Ni, and the balance Fe and inevitable impurities is used as a starting material The slab having 5-10% equiaxed crystal rate defined by the equiaxed crystal rate = the thickness of the equiaxed crystal part/the total thickness of the slab X 100 is produced from the molten steel having such components by a continuous casting method The segregation state of P which largely affects the toughness of the Ni-contg steel is control lable by the equiaxed crystal and P content in the above-mentioned manner Since this production process is effective to prevent the deterioration in the toughness in the central part of the sheet thickness, the low temp steel sheet having high safety is provided
TL;DR: The authors summarizes recent research on intergranular fracture and alloy design of L12 ordered Ni3X intermetallics and shows that boron is effective in ductilizing the first three alloys but not in Ni3Ge.
Abstract: This paper summarizes recent research on intergranular fracture and alloy design of L12 ordered Ni3X intermetallics The grain boundaries in Ni3AI, Ni3Ga, Ni3Si, and Ni3Ge are intrinsically brittle, and boron additions are effective in ductilizing the first three alloys but not in Ni3Ge The beneficial role of boron is to increase grain-boundary cohesive strength, to enhance plastic flow in the boundary region, and to disorder grain boundaries Boron is ineffective in ductilizing Ni3X alloys with × > 25% The room-temperature ductility of undoped Ni3Al can be improved also by change in grain shape from equiaxed to columnar
TL;DR: In this paper, the formation of this microstructure is analyzed in terms of the existence of an undercooled molten pool containing nucleants for the heterogeneous nucleation of b.c. iron.
Abstract: Laser alloying has been used to create hard surface layers on a ferritic stainless steel. Alloying elements were introduced very simply by painting the steel surface with a suitably charged paint. The materials obtained were examined by electron metallographic techniques and analysed by energy-dispersive spectroscopy and diffraction. Suitable control of laser conditions makes it possible to regulate the depth of substrate melting and the alloy composition. A second melting was necessary to homogenize the material and simultaneously to select the grain size. Microstructures obtained were typically equiaxed with grains of size 0.25–1 μm. The formation of this microstructure is analysed in terms of the existence of an undercooled molten pool containing nucleants for the heterogeneous nucleation of b.c.c. iron. Such microstructures are created because crystal growth requires diffusion and large undercoolings and because suitable nucleant particles are present.
[...]
TL;DR: In this paper, a model of a casting is presented which describes the freezing of a mushy zone, growing with a dynamically calculated undercooling at the dendrite tips, which resembles a combination of the Stefan and mushy zones problems.
TL;DR: The microstructure of a high-coercivity, bulk (Fe,Co)-Nd-B magnet was studied by optical and electron microscopy, X-ray diffraction and electron probe microanalysis (EPMA) as mentioned in this paper.
TL;DR: VADER's unique solidification mechanisms continuous produce cast ingots equiaxed characterized by a grain relatively fine structure as mentioned in this paper, and the understanding of these mechanisms and how they are affected by various alloy and process modifications is essential to the optimization of VADER.
Abstract: VADER's unique solidification mechanisms continuous produce cast ingots equiaxed characterized by a grain relatively fine structure. The understanding of these mechanisms and how they are affected by various alloy and process modifications is essential to the optimization of
TL;DR: In this article, the results of an investigation on the low cycle fatigue (LCF) behavior, at room temperature and 400°C for four conventional microstructures (Widmannstatten, basket-weave, equiaxed, and duplex) in a TC6 titanium alloy are presented.
Abstract: The results of an investigation on the low cycle fatigue (LCF) behavior, at room temperature and 400°C for four conventional microstructures (Widmannstatten, basket-weave, equiaxed, and duplex) in a TC6 titanium alloy arepresented. The fatigue crack nucleation and propagation in fatigue-tested specimens have been observed by scanning electron microscopy (SEM). The duplex microstructure is associated with the longest LCF life at room temperature and 400°C, while the Widmannstatten microstructure has the shortest. The crack initiation sites and propagation paths were examined and discussed. The cracks primarily initiated along slip bands on the specimen surface for all four microstructures. In addition, many voids appeared along slip bands for the equiaxed microstructure. By linking-up these voids, the formation of microcracks is realized. The propagation of interior cracks in specimens with Widmannstatten structure proceeded by cross-cutting Wa platelets by way of a plastic blunting mechanism, whereas for the equiaxed microstructure interior cracks grew by the linking-up of voids by way of a renucleation mechanism.
TL;DR: In this article, the influence of carbon content and alloying elements on the central billet quality of continuous casting has been studied and a difference in the CEZ behaviour was found between plain carbon steel and low alloy steels.
Abstract: The influence of carbon content and alloying elements on the central billet quality of continuous casting has been studied. In plain carbon steels the higher central equiaxed zone (CEZ) value (the area, expressed as a percentage, of equiaxed crystals) is obtained for medium carbon content. For lower and higher carbon contents, this value becomes smaller. However, the decrease is more pronounced in the latter situation than in the former and it is associated with a deterioration of the central quality of the billet. A difference in the CEZ behaviour was found between plain carbon steel and low alloy steels. This difference can be explained by the modification that alloying elements produce in the percentage of material that transforms from δ-ferrite into austenite during the peritectic reaction.MST/796