摘要:
When a rod-shaped workpiece (W) having an outer peripheral surface with a circular cross section is inductively heated to a quenching temperature while being conveyed at a predetermined velocity along an axial direction of the rod-shaped workpiece (W), the rod-shaped workpiece (W) being currently conveyed is heated to a predetermined temperature equal to or lower than the quenching temperature by a first heating coil (2A), which is electrically connected to a first high-frequency power supply (3) and has a constant output. Then, the rod-shaped workpiece (W) being currently conveyed is heated so as to be maintained at the quenching temperature by a second heating coil (2B), which is electrically connected to a second high-frequency power supply (4) and has a constant output.
摘要:
A method for heat treating a steel component, which comprises the steps of: (a) carbonitriding the steel component, and (b) austenitically nitrocarburizing the steel component.
摘要:
A bearing steel includes, as a metallographic structure, inclusions which contain complex oxysulfides including Rare Earth Metal, Ca, O, S, and Al, TiN, MnS, Al2O3, and complex oxides including Al and Ca, wherein, a number fraction of the complex oxysulfides in a total number of the inclusions is 50% to less than 100% and a number of complex oxysulfides having a major axis of 5 μm or more is 0.001 pieces to 2 pieces in an observed section of 1 mm2, and a number of TiN existing independently from the complex oxysulfides and having a major axis of 5 μm or more is 0.001 pieces to less than 1.0 piece in an observed section of 1 mm2.
摘要:
A method for surface hardening at least one part of a surface of a metal component is provided. The steps include a) enriching the at least one part of a surface of a metal component with at least one of carbon and nitrogen, and b) induction hardening the at least one part of the surface of the metal component.
摘要:
A bearing part according the present invention includes, as the chemical composition, by mass %, C: 0.95% to 1.10%, Si: 0.10% to 0.70%, Mn: 0.20% to 1.20%, Cr: 0.90% to 1.60%, Al: 0.010% to 0.100%, N: 0.003% to 0.030%, P: 0.025% or less, S: 0.025% or less, O: 0.0010% or less, and optionally Mo: 0.25% or less, B: 0.0050% or less, Cu: 1.0% or less, Ni: 3.0% or less, and Ca: 0.0015% or less, and a remainder including Fe and impurities; metallographic structure includes a retained austenite, a spherical cementite and a martensite; an amount of the retained austenite is 15% to 25%, by volume %; an average grain size of prior-austenite is 8.0 μm or less; and a number density of a void having a circle equivalent diameter of 0.02 μm to 3.0 μm is 2000 mm−2 or less in the metallographic structure.
摘要:
A carburisable steel alloy suitable for bearing components comprising, in percent by weight: C 0.05-0.5 wt. % Cr 2.5-5.0 wt. %, Mo 4-6 wt. %, W 2-4.5 wt. %, V 1 -3 wt. %, Ni 2-4 wt. %, Co 2-8 wt. %, optionally one or more of the following elements: Nb 0-2 wt. % N 0-0.5 wt. % Si 0-0.7 wt. %, Mn 0-0.7 wt. %, Al 0-0.1 5 wt. %, wherein the combined amount of Nb+V is within the range 1 -3.5 wt. %, the combined amount of C+N is within the range 0.05-0.5 wt. %, the balance being Fe and unavoidable impurities.
摘要:
A steel alloy for a bearing is provided. The alloy having a composition including from 0.04 to 0.1 wt. % carbon, from 11.5 to 13 wt. % chromium, from 1.5 to 3.5 wt. % molybdenum, from 0.3 to 0.8 wt. % vanadium, from 0.3 to 1.75 wt. % nickel from 6 to 9 wt. % cobalt, from 0.1 to 0.4 wt. % silicon, from 0.2 to 0.8 wt. % manganese, from 0 to 2 wt. % copper, from 0 to 0.05 wt. % niobium, from 0 to 0.1 wt. % aluminum, from 0 to 250 ppm nitrogen, from 0 to 30 ppm boron, and the balance iron, together with any unavoidable impurities.
摘要:
An outer ring, an inner ring, and a ball, each of which is a bearing part, are made of a quench-hardened steel containing not less than 0.90 mass % and not more than 1.05 mass % of carbon, not less than 0.15 mass % and not more than 0.35 mass % of silicon, not less than 0.01 mass % and not more than 0.50 mass % of manganese, and not less than 1.30 mass % and not more than 1.65 mass % of chromium with the rest consisting of an impurity. A contact surface thereof with another part has a nitrogen concentration of not less than 0.25 mass %. A remaining austenite amount in the contact surface is not less than 6 volume % and not more than 12 volume %.
摘要:
A rolled wire rod includes, as a chemical component, by mass %, C: 0.95% to 1.10%, Si: 0.10% to 0.70%. Mn: 0.20% to 1.20%, and Cr: 0.90% to 1.60%, the balance consisting of Fe and unavoidable impurities, in which a metallographic structure of the rolled wire rod includes, by an area ratio, 90% to 100% of pearlite, 0% to 5% of proeutectoid cementite, and 0% to 10% of degenerate pearlite having granular cementite, an average size of a pearlite block of the pearlite is 1.0 μm to 15 μm, and a maximum size of the pearlite block is 1 to 4 times the average size.
摘要:
A carbonitriding method that can improve the nitrogen permeating rate to render the carbonitriding process effective includes an atmosphere control step, and a heating pattern control step. The atmosphere control step includes an undecomposed NH3 partial pressure control step, and a CO/CO2 partial pressure control step. The undecomposed NH3 partial pressure control step and the CO/CO2 partial pressure control step are carried out in the atmosphere control step such that ac* defined by the following equation (1) is at least 0.88 and not more than 1.27, and α defined by equation (2) is at least 0.012 and not more than 0.020, where PN is the undecomposed ammonia partial pressure and PH is the hydrogen partial pressure in the heat treatment furnace, wherein a c * = ( Pco ) 2 K × Pco 2 ( 1 ) PCO: partial pressure of carbon monoxide (atm), PCO2: partial pressure of carbon dioxide (atm) K: equilibrium constant at +CO2 2CO α = P N 0.006 × ( P H ) 3 2 × ( 1.877 - 1.055 × a c * ) 100 . ( 2 )
摘要翻译:可以提高氮渗透速度使碳氮共渗工艺有效的碳氮共渗方法包括气氛控制步骤和加热模式控制步骤。 气氛控制步骤包括未分解的NH 3分压控制步骤和CO / CO 2分压控制步骤。 未分解的NH 3分压控制步骤和CO / CO 2分压控制步骤在气氛控制步骤中进行,使得由下式(1)定义的ac *为至少0.88且不大于1.27,α由 式(2)为0.012且不大于0.020,其中PN为未分解的氨分压,PH为热处理炉中的氢分压,其中ac * =(Pco)2 K×Pco 2(1 )PCO:一氧化碳分压(atm),PCO2:二氧化碳分压(atm)K:CO 2 + CO 2的平衡常数2COα= PN 0.006×(PH)3 2×(1.877-1.055×ac *)100。 (2)