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1–10 of about 10400 matches for cast iron
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Development of Ceramic Reinforced High Phosphorus Cast Iron Brake Shoe (20072329)
Proceedings of the 1st Korea-Japan Conference for Young Foundry Engineers P127-129
To develop the high quality brake shoe for railroad applications, ceramic reinforced high phosphorus cast iron brake shoes were prepared, and their structures and properties were investigated. Porous ceramic performs made of SiC were inserted in sand mold cavities, and melts of high P cast iron containing 3.3 mass%C, 1.7 mass%Si, 1.5 mass%Mn, 0.3 to 1.2 mass%P, 0.4 mass%Cr, 0.2 to 0.1 mass%V, 0 to 0.05 mass%B were cast at an atmospheric pressure. Pores of ceramic performs were almost completely filled by each melt, because the size of pores was rather large, about 2 to 6 mm. The microstructure of each cast iron was composed of steadite, cementite and flaky graphite distributed in pearlitic matrix. The amount of steadite increased with the increase in P content of cast iron, the amount of cementite also increased with the addition of minute amounts of B and they were distributed among cellular or dendritic ã-graphite eutectic. The wear resistance and the braking ability of each specimen were evaluated by using and original braking test machine and a full-size braking test machine. The full-size braking test almost showed the same results as the original braking test. Properties of cast iron brake shoe improved with additions of about 0.6 mass%P and 0.05 mass %B. Furthermore, that properties at an initial braking speed of above 95 km/h effectively improved with the reinforcement by ceramic performs. Properties of cast iron brake shoe enhanced with the increase in hard phases, viz., steadite and cementite distributed in pearlitic matrix. However the contact surface was heated over A1 temperature at the speed of over 95 km/h and pearlitic matrix containing hard phases was softened, which reduced those properties. On the other hand, the ceramic perform was harder than hard phases, and it was more excellent in the heat resistance than pearlitic matrix. Therefore, ceramic reinforced cast iron brake shoes showed higher properties at the speed of over 95 km/h.

CONSTRUCTING A FUTURE FOR CAST IRON (20050641)
Engineered Casting Solutions V 7 N 2 P 37 - 41 March/April 2005
The 2005 construction industry forecast shows sharp short-term gains for cast iron component shipments.

Microstructure and Properties of Cast Iron with Semi-Solid Process Using Cooling Plate Technique (20090364)
Proceedings of the Carl Loper Cast Iron Symposium, May 27-29, 2009, University of Wisconsin, Madison, WI
Semi-solid metal processing with the cooling plate technique is one of the key technologies for producing advanced materials. The multitude of cast iron families with their wide range of mechanical properties, and relatively low costs combined with the advantage of semi-solid processing allow production of high quality cast components from cast iron. The effect of semi-solid processing using the cooling plate technique on the microstructure and the properties of cast iron is studied. The investigated material is hypo-eutectic, hyper-eutectic gray iron, compacted graphite and ductile cast iron. The results indicated that the microstructure (primary austenite and graphite) becomes finer and more globular by increasing the fraction of solid. The tensile strength of semi-solid processed cast iron is relatively high compared with ordinary cast iron. The values of both the tensile strength and the elongation depend on the fraction of solid. The total fracture strength is observed to depend on the graphite morphology as well as the matrix contribution that mainly depends on fraction of solid. The wear resistance and damping capacity of cast iron were investigated as a function of the relative amount of primary fraction of solid.

Relationship Between Structure and Thermal Fatigue in Cast Iron (20082644)
Materials Science and Technology V4 March P222-226
Thermal fatigue of a material is determined by rupture stress, the elasticity modulus, heat conductivity, and thermal expansion. In addition to thermal expansion, one has to consider also the volume changes as a result of phase transformations. It is known that high rupture stress and high heat conductivity result in high resistance to thermal fatigue. A high Young’s modulus and high thermal expansion give low resistance to thermal fatigue. Cast iron is composite materials, consisting mostly of graphite, ferrite, and cementite. The graphite can occur in a number of different morphologies. It can be spherical, as in ductile cast iron, it can be flakelike, as in flake cast iron, but it can also be rodlike, as in vermicular or undercooled graphite. Many of the properties important for thermal fatigue are influenced by the shape of the graphite. By using various models to explain the properties of composite materials, the changes in the properties of cast iron as a function of graphite shape are analyzed. The analytical results are compared with experimental results. It is shown that the elasticity modulus and thermal expansion are lowest for flake graphite and that thermal conductivity is highest for this material. The conclusion is that gray cast iron has a better resistance to thermal fatigue than vermicular as well as nodular cast irons in spite of its lower rupture rate.

INJECTION OF FERRONIOBIUM IN GRAY CAST IRON (20000404)
Transactions of the American Foundrymen's Society V 107 Paper No 99-109 P 625-628, 1999 (4 p)
The addition of niobium (Nb) to cast iron and other high-carbon content materials is closely related to the carburization of the ferroalloy. Niobium carbides (NbC) form quickly and shield the ferroalloy lumps from melt contact. Therefore, the assimilation of Nb into the melt takes place through the dissolution of carbides, which requires long times to assure suitable recovery degrees. If the addition procedure is not properly optimized, carbide clusters and undissolved ferroalloy may subsist in the melt. Under similar conditions, the injection process has been more efficient than traditional practices of ferroniobium (FeNb) dumping, allowing 100% recovery degrees. This process also prevented the presence of carbide clusters and undissolved FeNb particles in the as-cast product with approximately 0.35 wt% Nb.

PRE-SHRINKAGE EXPANSION IN SEMI-CONTINUOUSLY CAST IRON PIPES (19680417)
Russian Castings Production (Feb. 1967) p. 82-84 Translated by the BCIRA
The influence of the steelmaking pig iron content of the cupola charge is shown. As the carbon equivalent or silicon content of the cast iron is increased, pre-shrinkage expansion increases and actual pro-pearlitic shrinkage decreases. If at a constant carbon equivalent an increased proportion of steelmaking pig iron is used in the charge, pre-shrinkage expansion decreases and actual pro- pearlitic shrinkage increases. Cast irons contain 30 or more elements in microscopic or sub-microscipic proportions. These exert an influence on the solidification process, the crust properties and consequently the shape of the kinetic shrinkage curve of the cast iron. Thus for example, the artificial introduction of trace amounts of up to 0.01% metallic arsenic to soft LK2 iron led to a considerable reduction in pre-shrinkage expansion and an increase in pro-pearlitic shrinkage. Oxygen and nitrogen in the free state retard graphitization and delay preshrinkage expansion. When oxygen and nitrogen are combined in the form of oxides and nitrides the reverse effect can be obtained under certain circumstances, since the sub-microscopic non- metallic inclusions formed act as inoculatns, promote graphitization, increase pre-shrinkage expansion and reduce actual pro-pearlitic shrinkage. Hydrogen stabilizes cementite. It usually enters the cast iron from moisture in the blast and readily diffuses into the metal. Diffusion on the other hand reduces its content before pouring. It has been established that as the silicon content of an iron decreases its nitrogen ocntent, whereas foundry pig, especially those with a high silicon content, contain somewhat less nitrogen.

HEAT CONTENT OF CAST IRON (19730868)
AFS Transactions 1973, p. 108-109, Preprint No. 73-33, $3.00
A mathematical assessment of the heat content of molten cast iron alloys suggests that the generally accepted value of 330 kwh/ton at 1572C (2750F) and with a rate of change of 10 kwh/ton/100oF (62 1/2C), is applicable to only those alloys of the metastable iron-cementite system. The heat content for alloys of the stable iron-cementite system is somewhat higher. Likewise, cast irons produced synthetically from steel, carbon and ferro-silicon have higher heat requirements to melt than do returns of the same composition.

BEHAVIOR OF NITROGEN IN CAST IRON (19680982)
Presented at the 35th International Foundry Congress (Oct. 6- 11, 1968) Kyoto, Japan, No. 41
The present investigation has been carried out in order to get further information about the behavior of nitrogen in white, gray and magnesium-treated cast irons by using the Kjeldahl method. First the influence of nitrogen on the rate of the first stage and the second stage graphitization of white cast iron, and the behavior of nitrogen in the iron during the annealing process were investigated. Second, the influence of silicon, manganese, sulphur, titanium and vanadium on the nitrogen content and the degree of graphitization of the gray cast iron were investigated. Last, the behavior of nitrogen in magnesium-treated cast iron was investigated. Nitrogen retards the graphitization of white cast iron. The nitrogen which governs the time for the completion of the second stage graphitization is not NS in as-cast white iron, but is NS in the iron just before the second state graphitization temperature. It has been considered from the experimental evidence that nitrogen can be removed from the iron by forming gaseous nitrogen. The degree of graphitization of gray cast iron decrease with the increase in N content, and vice-versa.

Application of complex inoculants in improving the process-ability of grey cast iron for cylinder blocks (20072169)
China Foundry V3 N2 P96-101
Effect of several complex inoculants on mechanical properties, process-ability and sensibility of grey cast iron used in cylinder block were investigated. The experimental results showed that the grey cast iron treated with 60% FeSi75+40%RE complex inoculants has tensile strength consistently at about 295 MPa along with good hardness and improved metallurgy quality. While the grey cast iron inoculated with 20%FeSi75+80%Sr compound inoculants has the best process-ability, the lowest cross-section sensibility and the least microhardness difference. The wear amount of the drill increases correspondingly with the increase of the microhardness difference of matrix structure, indicating the great effect of homogeneousness of matrix structure in the grey cast iron on the machinability of the grey cast.

AUSTEMPERING KINETICS OF LOW-CARBON ALUMINUM CAST IRON (19980337)
Transactions of the American Foundrymen's Society V 104 Paper 97-44 P 757-761, 1997 (5 p)
X-ray diffraction technique and light microscopy have been used to characterize the austempering kinetics of low-carbon austempered nodular/compacted aluminum cast iron (1.8% C, 2.2% Al). The results indicate that the microstructure and the principles of austempering transformation kinetics in these irons are similar to conventional austempered ductile cast irons. The rate of the first stage is very high, and the rate of the second stage is relatively similar to the normal austempered cast irons. The volume fraction of carbon-enriched austenite is lower than other austempered cast irons and is equal to low-carbon silicon cast iron.

1–10 of about 10400 matches for cast iron
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