Showing papers by "Bethlehem Steel published in 1991"

A comparison of the fracture behavior of two commercially produced heats of HY180 steel differing in sulfide type

Abstract: The mechanical properties of two heats of HY180 steel are compared after aging at 425 °C or 510 °C. The two heats of material appear very similar microstructurally, except most of the sulfides in one are believed to be titanium carbosulfides, while the sulfides in the other heat appear to be manganese sulfides. At both aging temperatures, the crack tip opening displacement at fracture (δIC) of the heat containing the titanium carbosulfides is over twice that of the heat containing the manganese sulfides. Measurements of the void volume fracture as a function of strain indicate that the titanium carbosulfide particles are much more resistant to void nucleation than are the manganese sulfide particles. The unusually high toughness of the heat containing the titanium carbosulfides is attributed to this increased resistance to void nucleation.

Metal recovery method and system for electroplating wastes

Abstract: The present invention relates to a method of completely recovering nickel and zinc metal from multiple plating process waste streams by first separating the waste streams into a clean, relatively constant flow and/or concentration fraction and a dirty, variable flow and/or concentration fraction. Metal is recovered from the clean fraction by ion-exchange so as to concentrate the extracted metals for direct return to the plating bath. The effluent from the ion-exchange step is then blended with the dirty, variable flow and concentration fraction. This blended flow is first neutralized and then precipitated in a two-stage process using a sodium hydroxide solution. The resultant slurry containing the metal precipitate is filtered to yield a filter cake containing recovered nickel and zinc. This filter cake can then be further processed to recover the metal for reintroduction into the plating bath or for other uses.

Intergranular stress corrosion cracking of alloy 600 and x-750 in high-temperature deaerated water/steam

Abstract: Intergranular stress corrosion cracking (IGSCC) has been studied in two similar nickel-base alloys, alloys 600 and X-750, in deaerated steam at elevated temperatures (380 °C) In both cases, IGSCC occurs through the nucleation, growth, and linkup of grain boundary voids rather than by grain boundary dissolution The rate of IGSCC is much faster in both alloys when they are heat-treated so that carbon is kept in solution instead of precipitating as grain boundary carbides This higher carbon content allows the formation of a higher methane pressure in grain boundary voids Slip impingement on the grain boundary plays a central role in nucleating a set of voids with a spacing of about 02 μm A second set of more closely spaced bubbles develops between these through the action of stress-assisted diffusion of material from the first set of bubbles

Effects of vanadium and processing parameters on the structures and properties of a direct-quenched low-carbon Mo-B steel

Abstract: The structures and mechanical properties of a series of thermomechanically processed, direct-quenched martensitic 0.1C-1.4Mn-0.5Mo-B steels containing from 0 to 0.24 wt pct va have been investigated and compared to those obtained after a conventional austenitizing-and-quenching treatment. For all processing conditions, vanadium additions to the base composition are found to increase hardenability (ideal critical parameter,D,); the largest effects (up to a 90 pct increase inDI) are noted when samples are hot-rolled prior to direct quenching. Vanadium additions are also observed to provide significant strengthening in the quenched-and-tempered condition as the result of the precipitation of fine V-Mo carbides. The strengthening increment due to these precipitates is approximately 100 MPa/0.1 wt pct V over the range of vanadium additions examined. At the same time, however, these precipitates reduce notch toughness; on the average, the 20 J transition temperature increases by about 4 °C for each 10 MPa increment in yield strength. For the conditions examined, the best balance of strength and toughness is obtained in direct-quenched samples which are control-rolled(i.e., rolling is completed below the austenite recrystallization temperature) prior to quenching.

IGSCC crack growth of alloy 600 and X-750 in steam

Abstract: The crack growth rate for IGSCC has been measured in two nickel base alloys, Alloy 600 and X-750, in deaerated, superheated steam between 300 and 400° C. Measurements were made using MWOL ...

Hot-rolled microalloyed steel and its use in variable-thickness sections

Abstract: A vanadium-nitrogen microalloyed steel is continuously hot rolled to C-shaped sections that meet property requirements for side rails of truck frames with no heat treatment. Sections with different thicknesses of the web and flange regions can also be prepared by the same processing. The composition of the steel is from about 0,16 to about 0.20 percent carbon, from about 1.2 to about 2.0 percent manganese, from about 0.45 to about 0.55 percent silicon, from about 0.10 to about 0.30 percent vanadium, from about 0.001 to about 0.030 percent aluminum, from about 0.010 to about 0.027 percent nitrogen, less than about 0.080 percent phosphorus, less than about 0.030 percent sulfur, balance iron totalling 100 percent, with all percentages by weight. Variations of this steel containing either from about 0.01 to about 0.02 percent titanium or 0.04 to about 0.07 percent aluminum are also permissible.

Apparatus for retaining slag during the discharge of molten metal from a tundish

Abstract: Apparatus for retaining slag in a tundish or a ladle or similar vessel containing molten metal such as used in the steel industry. A refractory nozzle member and a refractory retainer member are secured to the bottom of the vessel around the molten metal discharge orifice. A refractory plug member of a density between that of the molten metal and the slag is positioned laterally within the retainer member but free to move vertically during discharge of the molten metal from the vessel.

The Effect of Chromium Content (0 to 35%) in Fe-Cr Alloys on Corrosion Rates and Mechanisms in 1.0 N Sulfuric Acid

Abstract: The effect of chromium content (0 to 35 percent) in Fe-Cr alloys on their dissolution in 1.0 N sulfuric acid was investigated. Corrosion rates increase with increasing chromium content. Corrosion rates were determined by three electrochemical techniques (Tafel extrapolation, three-point, and polarization resistance methods) and were compared with the rates determined by weight-loss measurements. The cathodic hydrogen evolution reaction is independent of the chromium content; that is, the exchange current density (i0) and the Tafel slope (βc) are essentially constant with changes in chromium content. The anodic Tafel constant (βa) for alloy dissolution is also independent of the chromium content. The increase in corrosion rates observed with increasing chromium content is directly proportional to the change in the active direction of anodic open-circuit potential and, therefore, also the corrosion potential in this case. Some effects of this phenomenon on pitting and crevice corrosion in chloride ...

Apparatus and method for replacing a bull gear on a trunnion

Abstract: An apparatus for installing a new bull gear onto a trunnion shaft of a BOF, the apparatus comprising a first stop removably attached to the end face of a turnnion shaft, a gear press shaft extending through an aperture within the first stop means, the gear press shaft having a first end portion with an enlarged segment inserted into a recess provided within the trunnion shaft, a second stop adjustably attached to a second end portion of the gear press shaft, a gear press plate removably attached to the gear and encircling the gear press shaft between the first and second stops and a jack means located between the gear press plate and the second stop.

Top chord member for railway cars

Abstract: A sidewall and top chord member for an open top gondola or hopper railway car. The top chord member is a lightweight rectangular tubular extrusion of aluminum having a pair of spaced wear pads on the top surface thereof to contact rotary or shaker type car unloading equipment.

Apparatus for retrieving a slag sample during a steelmaking operation

Abstract: Apparatus for retrieving a sample of slag from the surface of molten steel contained in a ladle. A hoist positioned above the ladle lowers and raises an elongated metal rod which has cardboard and metal sleeves surrounding the lower portion of the elongated metal rod. A clean sample of molten slag tightly adheres to the metal sleeve as it is raised from the molten slag layer. The metal sleeve and slag sample are easily removed from the elongated metal rod for analysis.

Metal sheet and method for producing the same

Abstract: Disclosed is a method for producing a metal sheet having a full-hard central portion extending between at least two softer side edge portions of the sheet. The method comprises the step of heating the side edge portions of the sheet portions of the sheet to a higher temperature than the central portion.

Retaining Structures and Excavations

Abstract: Structures that retain lateral forces from soil and/or water are composed of various materials, constructed by numerous procedures and methods, and are used for many purposes. In this chapter the manner of support is used to classify the different types of structures. Reinforced earth structures are not included, as that type of structure is covered in Chapter 21. The three means of support consist of restrained, gravity, and cantilever systems. Each support system has variations—the restrained system having the greatest number and cantilever the least. Gravity structures are far more numerous than the other two since they are used for the construction of many small structures such as soil-retaining walls. The largest retaining structures are of the gravity type. Restrained structures are prominent in the construction of waterfront facilities and excavations. Cantilever structures are the least used because they allow large deflections to occur. Combinations of support types are sometimes used.

Method and apparatus for dross free burning of slabs

Abstract: A method and torch-cutting apparatus for slabs to prevent dross from forming on the underside of the slabs in the area of a cut includes a device to be positioned beneath a slab. The device applies a tight clamping pressure to the underside of the slab in the area of the cut to thereby prevent dross from flowing laterally and forming on the underside of the slab in the area of the cut during the cutting operation.

Protective shield having heat conductive properties

Abstract: A shield comprising a refractory material resistant to pentration by a continuous stream of molten steel and a retaining means to hold the refractory material contiguous to a heat absorption surface.

Railway car with vented bolster to facilitate the thawing of lading

Abstract: A railway car suitable for rotary or bottom dump unloading. The body bolster is fitted with vents to permit a heating of the slope floor at the ends of the car to thaw the lading prior to unloading.

Apparatus for measuring variations in windings of coiled material

Abstract: Apparatus for measuring lap to lap variations between windings of a coiled sheet product comprising a light source, a light measuring cell, and a light directing chamber located between the light source and the light measuring cell. The light directing chamber includes a cavity adapted to receive a shutter, and a light directing duct having a slot communicating with the cavity of the light directing chamber. The slot is adapted to provide an opening for inserting the shutter into the interior portion of the light directing duct.

High-sensitivity interferometric technique for strain measurements

Abstract: A high sensitivity strain measurement procedure that combines moire interferometry and digital image processing, has been successfully implemented to determine thermally induced strains in electronic components. The technique is called Fractional Fringe Moire Interferometry (FFMI). It produces whole field displacement information that are used to compute strains in a certain plane. Displacements in the submicron domain are detected with excellent spatial resolution over the area of interest. An example is presented here to illustrate the use of the technique to monitor thermally induced deformations in a specimen made from a plastic DIP device. The specimen was uniformly heated from room temperature to 90 degree(s)C, and the resulting moire fringe patterns were recorded, analyzed using digital-image-processing and in plane displacements in the package were determined. Strain components were then computed by simple differentiation of the acquired displacement fields. Contour maps showing actual thermo/mechanical strain components in the device were constructed. Those maps can provide an excellent tool for strain analysis of microelectronic devices regardless of the structural complexity of the device.© (1991) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Durability and Protection of Foundations

Abstract: Failure of structures due to deterioration of the foundations occurs infrequently in some applications and far too frequently in others. Waterfront facilities (particularly in marine and tidal exposures) have a much higher incidence of material deterioration than land-based facilities. Protection of materials in aggressive environments and operations (or use) has long been recognized as a necessity. Satisfactory protection systems are available, but are, in many instances, misapplied or ignored. Foundation deterioration is. usually thought of in terms of electrochemical and chemical phenomena; however, causes of deterioration also include heat, abrasion, and inadequate time-dependent strength properties. Deterioration due to low-temperature environments and temperature cycling occurs rarely and is usually related, in the case of concrete, to severe exposure while curing. Foundations are not subjected to the temperature extremes that the supported structures are. This is a decided benefit.