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RECOMMENDED PRACTICE FOR REPAIR WELDING AND FABRICATION WELDING OF STEEL CASTINGS (19690958)
Published and Distributed only by Steel Founders' Society of America, Westview Towers, 21010 Center Ridge Road, Rocky River, OH 44116
The 50 page booklet contains descriptions of all processes used in welding steel castings, together with applicable specifications. Electrodes used for both gas and arc welding-- composition, properties and operating characteristics, as well as weld-metal properties--are covered. One section details recommended welding procedures for the most common types of carbon steel and low alloy steel castings, and for each type gives recommended electrode classifications, sizes, welding currents, deposition techniques, preheat and interpass temperatures, as well as postwelding heat treatments. The alloy steels covered include: Low Carbon Steel Castings, Compositions of CArbon and Low Alloy Steel Castings, Medium-Carbon Steel Castings, Medium-High-Carbon Steel Castings, High-Carbon Steel Castings, Nickel Steel Castings, Nickel-Chromium Steel Castings, Nickel-Chromium-Molybdenum Castings, Nickel Molybdenum, Medium- Manganese Steel Castings, Manganese-Molybdenum Steel Castings, Austenitic Manganese Steel Castings, Chromium-Molybdenum Steel Castings, Manganese-Chromium-Nickel-Molybdenum Steel Castings, Chromium Steel Castings, Molybdenum Steel Castings and Copper- Manganese-Silicon Steel Castings.

Steel Castings versus Steel Weldments (19681085)
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Cast steel is steel. Forged steel and rolled steel for weldments are steel. Certain physical values of steel pertain to steels regardless of the method of manufacture, such as Modulus of Elasticity, Modulus of Rigidity, Poissons Ratio, density, volume changes, melting and solidification temperatures, thermal, electrical and magnetic values. The designers and buyers of steel castings often confuse the situation by placing emphasis on castings and compare steel castings with other casting products. Comparison should not be permitted on this level as the physical values of steel are different from those of other cast products. There are variations that exist in the properties of cast steel and rolled steel and weldments because of the method of manufacture of the steel products. It is the purpose of this data file section to relate these differences and to illustrate their importance from the standpoint of the competitive position of cast versus wrought steel.

PREDICTION OF REOXIDATION INCLUSION COMPOSITION IN CASTING OF STEEL (20071943)
Metallurgical And Materials Transactions P571-588
A model is developed to calculate the composition of reoxidation inclusions that form during pouring of steel castings. The software package Thermo-Calc is used to obtain the inclusion phase fractions and compositions as a function of the temperature and oxygen content of the steel. Oxygen is assumed to be continually absorbed by the steel until the liquidus temperature is reached. Both lever rule and Scheil-type analyses are performed. The model is applied to reoxidation of two carbon steels, one low-alloy steel and one high-alloy steel. The effects of variations in the steel composition and the oxygen absorption rate on the inclusion composition are investigated in a parametric study. The mass fraction of absorbed oxygen is determined by matching predicted with previously measured reoxidation inclusion compositions for the various steels. Good agreement is obtained for most phases present in the inclusions. Interestingly, the agreement in the inclusion compositions occurs for all steel grades, when the percentage of absorbed oxygen is equal to 0.9 wt pct. This value is explained using a separate model for the rate of oxygen to be achieved. The model is then used to calculate the amount of alloy elements consumed and inclusions formed as a function of the oxygen boundary layer thickness in the atmosphere and the integrated free surface area of the liquid steel during pouring. It is found that for unprotected liquid steel transfer operations, such as tapping and ladle filling, the integrated free surface area and exposure time product can reach values of the order of 100 m2s per ton of steel, and that the air-to-steel volume ration during pouring can be as large as 40. It is concluded that, in order to create a comprehensive tool for simulating reoxidation formation, more detailed models are needed for the external oxygen transfer in the atmosphere, the flow of the liquid steel during pouring, and the internal transport and reactions of chemical species in the steel.

STEEL CASTINGS VERSUS STEEL WELDMENTS (19710413)
Casting Engineering March/April, 1971, p. 27-28, 30-32, 34- 36
The design engineer who employs cast steel over steel weldments is allowed much more freedom in the following design areas: 1) Tapered wall sections, compounded curve construction, internal curve construction, cored holes and passages are available when steel castings are employed. 2) Thick sections adjacent to thin sections can be easily made such as, for example, the addition of bosses. Weldments are limited by the thickness of the rolled plates employed. 3) The use of complicated sections in a design is uneconomical for weldments, especially when large amounts of welding are required. Complicated sections are produced easily as steel castings. Steel castings have reduced localized stress concentration because of the smoother curved construction, well-radiused fillets and section junctions. 6) Greater structural rigidity is an inherent attribute of steel castings because of the design freedom resulting from local increasing of section thickness when necessary. Fewer internal stresses usually exist in steel castings than in fabrication weldments. Steel castings are usually stress relieved or heat treated whereas weldments are seldom stress relieved. Less distortion is encountered in steel castings than in weldments because of the localized effect of the heat of welding. There are no joints in steel castings and since no human element is involved in joining, as in welding, no leaks or partial lack of attachment can occur.

A Newly-developed High Wear Resistance Cast Hot-forging Die Steel (20072479)
ISIJ International V47 N9 P1335-1340
The alloying design of the cast hot-forging die steels was analyzed. The key property and parameters for the alloying design were selected. The cast hot-forging die steel with high wear resistance was developed through optimizing the parameters. The wear resistance of the newly-developed cast die steel was evaluated in comparison with commercial H13 steels and 3Cr2W8V steel. The wear mechanism is also discussed. The newly-developed cast die steel takes VC as predominant carbide with solid solution strengthening of Cr and Mo. The cast die steel was found to have significantly lower wear rate than normal H13 steel and 3Cr2W8V steel, and almost he same wear rate as high-purified H13 steel. The high wear resistance of the new-developed cast die steel could be attributed to the reasonable alloying design and no sensitivity to detrimental function of S and P. Under the elevated-temperature air at 400°C, the wear for the cast die steels and commercial hot-forging die steels is a typical oxidation wear.

PRODUCTION OF LARGE STEEL CASTINGS BY USING LD COVERTERS (19680973)
Presented at the 35th International Foundry Congress( Oct. 6- 11, 1968) Kyoto, Japan, No. 32
LD molten steel was used for making various kinds of steel castings. One of the largest was a casting of rolling mill housing and weighting 320 tons in pouring weight. For molding such a large casting a number of chill blocks were buried under the bottom surface of drag mold. Cope mold was divided into three parts and after drying separately these mold members were assembled by a flask. The core for screw down nut hole was rammed within a mold steel case of the core form and a water-cooling pipe was inserted into the center of the core. Since LD steel has lower contents of impurities, it has higher ductility than electric arc steel of equal carbon content. In order to make the mechanical strength of LD cast steel, the contents of carbon and manganese were increased by amounts of 0.02 and 0.05% respectively in comparison with electric arc steel. LD cast steel thus produced was higher in fatigue strength that the conventional electric steel.

Thermodynamic Evaluation of Formation of Oxide-Sulfide Duplex Inclusions in Steel (20083484)
ISIJ International, Vol. 48, No. 11, P1552-1559, 2008
Calcium is widely used for improving the castability of liquid steel, as well as for improvement of steel cleanliness and inclusion modification for better quality steel. Calcium modifies solid alumina inclusions, arising out of deoxidation of liquid steel, into liquid calcium aluminate. Depending upon the steel composition, calcium sulfide (CaS) and/or various forms of calcium aluminates may form. Sulfides are often associated with the oxide phase, which is typically known as oxide-sulfide duplex inclusion. Formation of solid calcium sulfide must be avoided during the ladle treatment of liquid steel, since it is detrimental to the castability of steel. In the present work a thermodynamic model has been developed for predicting the formation of oxide-sulfide duplex inclusions arising out of competitive reactions between [O], [S] and [Ca] in Al-killed steel. The model predictions of the present work were compared with those reported in literature, as well as with the types of inclusions observed in steel samples collected from the plant. Reasonably good agreements amongst them were observed. The results indicated that in order to achieve completely liquid calcium aluminate without forming any sulfides the sulfur content of liquid steel must be sufficiently low, With increasing S content of liquid steel, complete modification of alumina inclusions into liquid calcium aluminum becomes difficult. The maximum sulfur content to avoid formation of CaS depends upon the steel composition, principally aluminum. The sulfide inclusions are often a solid solution of CaS and MnS. Thermodynamic analysis for this system was also carried out. Base don the analysis in the present work, it is possible to predict the influence of sulfide composition on formation of duplex inclusions.

WHAT IT TAKES TO MAKE ALLOY STEEL (19710171)
Steel Furnace Monthly (August 1970), p. 223-225
A number of elements are added to the molten steel either in the form of alloys or iron (master alloy) commonly known as ferro alloys or as metals to achieve certain desirable changes, such as deoxidation of the molten metal, control of grain size, improvement of mechanical and physical properties of steel, improvement of corrosion resistance of steel or attainment of specific effects. Elements such as manganese, silicon, chromium, molybdenum, tungsten, vanadium, etc., are mostly introduced in the molten steel in the form of ferro-alloys. Nickel, cobalt, aluminum, etc., are added as metals. Ferro-chromium - Chromium is added in almost all alloy steels either as low-carbon ferrochrome or high-carbon ferro-chrome depending upon the type of steel and process adopted. Addition of chromium improves mechanical properties, creep resistance, and corrosion resistance. Nickel, in conjunction with cromium, it forms a series of anti-corrosive heat resisting steels. Nickel is not only used for the manufacture of stainless steel but also a wide variety of constructional steels, including case-hardening steels and in die-blocks; as compared with carbon steels, nickel steels show greater toughness and greater strength combined with greater ductility both in the normal and heat-treated conditions. Ferrmanganese - Manganese when added in alloy steels deoxidizes and cleans molten steel; combines with sulphur to improve the hot working property of the steel; and by forming in alloy, improves the strength, toughness and response to heat treatment of various steels. Tungsten is an essential speed steels, the tungsten content is about 18%.

Steel Slag Aggregates in Bituminous Mixtures -- Final Report (20091157)
Bureau of Bridge and Roadway Technology, Pennsylvania Department of Transportation, 1992
This report covers the evaluation of steel slag from open hearth, basic oxygen, or electric arc steel making processes used as an aggregate for bituminous asphalt mixes. Bituminous asphalt mixes demonstrate several good mix characteristics with steel slag aggregates. The characteristics include high stability, high skid resistance, longer heat retention after mixing, and ease of compaction without "shoving" in front of a roller compactor. Steel slag aggregates are abundant in Pennsylvania due to the once large steel processing centers. However, steel slag aggregates have potential for volumetric expansion due to the fast occurring hydration of Calcium Oxide and the slower hydration of Magnesium Oxide found in steel slag. For this reason, steel slag aggregates were evaluated in a Pennsylvania FB-2 binder and wearing course and in an FJ-1 wearing course to determine any potential for blow-ups or pop-outs at the pavement surface. Laboratory test results indicated no problems with any of the steel slag bituminous mixes. Steel slag specimens demonstrated a higher percent retained tensile strength and stability with less stripping than limestone specimens. The percent swell of the steel slag specimens were also with tolerable limits. Field pavements also had no problem.

Chromium and Nickel Aerosols in Stainless Steel Manufacturing, Grinding and Welding (20072439)
American Industrial Hygiene Association Journal V42 P596-601
Composition, morphology and solubility of chromium and nickel in fumes from stainless steel manufacturing, based on ferrochrome, and in dusts from grinding of stainless steel, were studied. The results were compared with corresponding analyses of stainless steel welding fumes. In fumes from the melting of ferrochrome and stainless steel, as well as in dusts from the grinding of stainless steel, chromium is only slightly oxidized to the hexavalent state. Therefore, chromates are present in very low concentrations in contrast to manual metal arc chromates. Nickel occurs in fumes from stainless steel manufacturing mainly as metallic alloyed element in the iron matrix or in small amounts as oxide (NiO). In stainless steel welding fumes, separate nickel oxide particles have been found. Airborne particles originating from the melt are typically round and possibly covered by a slag layer.

1–10 of about 14000 matches for steel
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