Bethlehem Steel

About: Bethlehem Steel is a based out in . It is known for research contribution in the topics: Coating & Corrosion. The organization has 1529 authors who have published 1559 publications receiving 19098 citations. The organization is also known as: Bethlehem Steel Corporation.

Method of injection molding a structural foamed thermoplastic article having a uniform swirl-free and indent-free surface

Abstract: A process for producing a swirl-free, indent-free foamed thermoplastic structural article in which water is utilized as a foaming agent. Water and a melted thermoplastic resin are mixed together in an extruder to form a pressurized foamable mixture. The foamable mixture from the extruder is collected in an accumulator and from there is delivered to a cavity in a mold in a suitable clamping device. The pressure in the cavity is lower than the pressure of the foamable mixture in the accumulator or extruder therefore when the foamable mixture enters the cavity the foaming agent is released and the thermoplastic resin is frothed and expands to completely fill the cavity. The melted foamed thermoplastic resin cools in the mold and solidifies to form a foamed thermoplastic structural article. The quantity of water introduced into the extruder is between about 0.1 weight percent to about 0.5 weight percent of the thermoplastic resin charge in the extruder. To produce a swirl-free foamed thermoplastic structural article the quantity of water introduced into the extruder is between about 0.1 weight percent and about 2.0 weight percent of the thermoplastic resin charge in the extruder.

Method of improving the ductility of the coating of an aluminum-zinc alloy coated ferrous product

Abstract: This invention relates to an aluminum-zinc alloy coated ferrous product whose coating is highly ductile, and to the method whereby such improved coating ductility may be realized. The process is characterized by the steps of thermally treating the aluminum-zinc alloy coated product by heating to a temperature between about 200° F. (93° C.) and 800° F. (427° C.) and holding for a period of time to effect metallurgical structure changes, among them being the precipitation of a second phase incoherent with the matrix, followed by slow cooling to at least 400° F. (205° C.). The resulting product is characterized by an aluminum-zinc alloy coating with a hardness no greater than about 115 VHN, and preferably no greater than about 110 VHN.

Method of reducing ores

Abstract: METHOD OF REDUCING ORES Abstract of the Disclosure Iron ore and a mixture of methane and hydrogen are red into a plasma arc torch and form a swirling flim of material that slowly-descends the walls of the torch. The ore is reduced in the torch, and metallic iron is collected in a crucible below the torch.

Effects of zinc coatings on the stress corrosion cracking and hydrogen embrittlement of low-alloy steel

Abstract: The effects of electroplated and hot-dip zinc coatings on the fracture of low-alloy steel AISI 4140 bars tempered to hardnesses in the range Rc 33 to 49 were studied. Either electroplated or hot-dip zinc coatings decrease resistance to stress corrosion cracking,i.e., they reduceKsc, the threshold stress intensity for stress corrosion cracking in 3.5 wt pct NaCl solution. AboveKscelectroplated-zinc coatings do not appear to affect the crack-growth rate, although the incubation period prior to the onset of crack growth is reduced. Hot-dip zinc coatings increase stress corrosion crack growth rates slightly because of the additive effect of internal dissolved hydrogen. Hot-dip zinc coatings reduce the critical stress intensity for fracture in the absence of a corrosive environment because of embrittlement by internal hydrogen which is released from traps during hot-dip coating and confined by the inter metallic coatings which form on the steel surface in the hot dip bath. A simple fracture mechanics analysis indicates that either increasing diameter or the presence of a zinc coating lowers the critical hardness at which the stress corrosion cracking of structural bolts can occur.