An iron-based alloy composition including: boron (B): 1. 6-2.4 wt. %; carbon (C): 2.2-3.0 wt. %; chromium (Cr): 3.5-5.0 wt. %; manganese (Mn): below 0.8 wt. %; molybdenum (Mo): 16.0-19.5 wt. %; nickel (Ni): 1.0-2.0 wt. %; silicon (Si): 0.2-2.0 wt. %; vanadium (V): 10.8-13.2 wt. %; and balanced with iron (Fe). Further, an item including a substrate portion and a hardfacing coating bonded to the substrate portion, wherein the hardfacing coating is made by an overlay welding process using the iron-based alloy composition.

The present invention relates to an iron-based alloy that is able to provide a coating on a substrate, the coating having simultaneously high hardness and wear resistance. The iron-based alloy consists of 3.0-7.0% by weight Cr; 1.3-3.0% by weight C; 0.2-2.0% by weight B; 2.0-10.0% by weight V; optionally 1.5% by weight or less Si; optionally 1.0% by weight or less Mn, optionally 2.0% by weight or less Mo; optionally 1.5% by weight or less Ni; the balance being Fe and unavoidable impurities. The present invention further relates to an article comprising a substrate and coating formed thereon, the coating being formed from the alloy, and to a method for forming a coated article. The method preferably employs HVOF, laser cladding or plasma cladding.

The present invention relates to an iron-based alloy that is able to provide a coating on a substrate, the coating having simultaneously high hardness and wear resistance. The iron-based alloy consists of 3.0-7.0% by weight Cr; 1.3-3.0% by weight C; 0.2-2.0% by weight B; 2.0-10.0% by weight V; optionally 1.5% by weight or less Si; optionally 1.0% by weight or less Mn, optionally 2.0% by weight or less Mo; optionally 1.5% by weight or less Ni; the balance being Fe and unavoidable impurities. The present invention further relates to an article comprising a substrate and coating formed thereon, the coating being formed from the alloy, and to a method for forming a coated article. The method preferably employs HVOF, laser cladding or plasma cladding.

The coupler system of a railway car truck is constructed such that basic overall appearance may be maintained, but the actual material of which it is constructed is changed. According to one embodiment, the coupler is constructed from cast austempered ductile iron; whereas cast iron has a density, 0.26 lbs/in{circumflex over ( )}3, which is approximately 8% less than steel, 0.283 lbs/in{circumflex over ( )}3, thereby allowing for a reduction in weight over steel. A suitable austempering process is used to produce the austempered metal coupler and components thereof. A second benefit of embodiments of the present invention provides for a more efficient use of materials, meaning less metal is used to make the same final shape, as a way of reducing the coupler weight. Both factures combined allow for a lighter weight coupler, while utilizing the standard designs. Alternate coupler configurations are disclosed for further reducing coupler weight.

The coupler system of a railway car truck is constructed such that basic overall appearance may be maintained, but the actual material of which it is constructed is changed. According to one embodiment, the coupler is constructed from cast austempered ductile iron; whereas cast iron has a density, 0.26 lbs/in{circumflex over ( )}3, which is approximately 8% less than steel, 0.283 lbs/in{circumflex over ( )}3, thereby allowing for a reduction in weight over steel. A suitable austempering process is used to produce the austempered metal coupler and components thereof. A second benefit of embodiments of the present invention provides for a more efficient use of materials, meaning less metal is used to make the same final shape, as a way of reducing the coupler weight. Both factures combined allow for a lighter weight coupler, while utilizing the standard designs. Alternate coupler configurations are disclosed for further reducing coupler weight.

A method for producing a zinc or zinc-alloy coated steel sheet with a tensile strength higher than 900 MPa, for the fabrication of resistance spot welds containing in average not more than two Liquid Metal Embrittlement cracks per weld having a depth of 100 μm or more, with steps of providing a cold-rolled steel sheet, heating cold-rolled steel sheet up to a temperature T1 between 550° C. and Ac1+50° C. in a furnace zone with an atmosphere (A1) containing from 2 to 15% hydrogen by volume, so that the iron is not oxidized, then adding in the furnace atmosphere, water steam or oxygen with an injection flow rate Q higher than (0.07%/h×α), α being equal to 1 if said element is water steam or equal to 0.52 if said element is oxygen, at a temperature T≥T1, so to obtain an atmosphere (A2) with a dew point DP2 between −15° C. and the temperature Te of the iron/iron oxide equilibrium dew point, then heating the sheet from temperature T.sub.1 up to a temperature T.sub.2 between 720° C. and 1000° C. in a furnace zone under an atmosphere (A2) of nitrogen containing from 2 to 15% hydrogen and more than 0.1% CO by volume, with an oxygen partial pressure higher than 10.sup.−21 atm., wherein the duration to of heating of the sheet from temperature T.sub.1 up to the end of soaking at temperature T.sub.2 is between 100 and 500 s, soaking the sheet at T.sub.2, then cooling the sheet at a rate between 10 and 400° C./s, then coating the sheet with zinc or zinc-alloy coating.

A composite roll for rolling having a structure comprising centrifugally cast outer and intermediate layers of an Fe-based alloy integrally fused to an inner layer of ductile cast iron; the outer layer having a composition comprising by mass 1-3% of C, 0.3-3% of Si, 0.1-3% of Mn, 0.5-5% of Ni, 1-7% of Cr, 2.2-8% of Mo, 4-7% of V, 0.005-0.15% of N, and 0.05-0.2% of B, the balance being Fe and inevitable impurities; the intermediate layer containing 0.025-0.15% by mass of B; the B content in the intermediate layer being 40-80% of that in the outer layer; and the total amount of Cr, Mo, V, Nb and W in the intermediate layer being 40-90% of that in the outer layer.

A composite roll for rolling having a structure comprising centrifugally cast outer and intermediate layers of an Fe-based alloy integrally fused to an inner layer of ductile cast iron; the outer layer having a composition comprising by mass 1-3% of C, 0.3-3% of Si, 0.1-3% of Mn, 0.5-5% of Ni, 1-7% of Cr, 2.2-8% of Mo, 4-7% of V, 0.005-0.15% of N, and 0.05-0.2% of B, the balance being Fe and inevitable impurities; the intermediate layer containing 0.025-0.15% by mass of B; the B content in the intermediate layer being 40-80% of that in the outer layer; and the total amount of Cr, Mo, V, Nb and W in the intermediate layer being 40-90% of that in the outer layer.

A terrific stainless steel alloy and turbocharger kinematic components are provided. A ferritic stainless steel alloy includes or consists of, by weight, about 20% to about 35% chromium, less than about 2% nickel (i.e., from 0% to about 2%), about 1% to about 4% carbon, about 1.5% to about 1.9% silicon, less than about 0.4% nitrogen (i.e., from 0% to about 0.4%), about 0.5% to about 15% molybdenum, less than about 1% niobium (i.e., from 0% to about 1%) and a balance of iron, and other inevitable/unavoidable impurities that are present in trace amounts. The turbocharger kinematic components are made at least in part using this stainless steel alloy.

An iron-based welding and forging alloy with a complex chemistry produces a dense, homogenous weld deposit that is resistant to hardness loss at elevated temperatures with less reliance on cobalt content. Such an alloy may comprise, in approximate percentages by weight: cobalt: 5-25; chromium: 7-14; tungsten: 2.5-10; molybdenum: 2-9; nickel: 1-6; carbon: 0.01-5; manganese: 0.01-3; with iron and residual elements comprising the balance. The residual elements may include one or more of the following: silicon, vanadium, phosphorus, and sulfur. The amounts of the residual elements may be up to 1% by weight. The inventive alloys may be provided in any suitable form for welding purposes, including metal-core TIG (GTAW), coated electrode (SMAW) and metal-core-wire (MCAW). The inventive alloy combinations may be fabricated as welding filler, providing resistance to high temperature softening, facilitating use in applications that previously dictated a specific cobalt-based material.