HEAT TREATMENT METHOD OF ROD-SHAPE WORKPIECE

    公开(公告)号:US20190241986A1

    公开(公告)日:2019-08-08

    申请号:US16312368

    申请日:2017-05-26

    申请人: NTN CORPORATION

    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.

    Carbonitriding method, machinery component fabrication method, and machinery component
    10.
    发明授权
    Carbonitriding method, machinery component fabrication method, and machinery component 有权
    碳氮共渗法,机械部件制造方法和机械部件

    公开(公告)号:US09062355B2

    公开(公告)日:2015-06-23

    申请号:US12296054

    申请日:2007-04-03

    申请人: Chikara Ohki

    发明人: Chikara Ohki

    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)