摘要:
The present invention provides a Fe-group-based soft magnetic powder that is used for the pressed powder magnetic cores for a choke coil, reactor coil, etc., and that has a higher magnetic permeability. At least one selected from Fe, Co, or Ni that is generally used is used as the main component of the Fe-group-based alloy (iron-based alloy) soft magnetic powder. The soft magnetic powder is produced by adding a small amount of Nb (0.05-4 wt %) or V, Ta, Ti, Mo, or W, to the molten metal and by means of an inexpensive method such as the water-atomizing method.
摘要:
The present invention provides a duplex stainless steel sheet with excellent press-formability which defines the ingredients of the steel, Ni balance, and austenite phase rate to obtain a 0.2% proof stress and Erichsen value equal to that of SUS304 or another austenitic stainless steel, that is, a duplex stainless steel sheet which contains, by mass%, C: 0.05% or less, Si: 0.5 to 3%, Mn: 1 to 5%, Cr: 16 to 21%, Ni: 1 to 6%, Cu: 0.5 to 3%, and N: 0.07% or less, has an Ni-bai. value given by the following formula of -7.5 to -3.5, has a balance of Fe and unavoidable impurities, has an austenite phase rate of 50% to 95%, and has a balance of ferrite phases: €ƒ€ƒ€ƒ€ƒ€ƒ€ƒ€ƒ€ƒNi-bal.=30(C+N)+Ni+0.5Mn+0.3Cu-1.1(Cr+1.5Si)+8.2€ƒ€ƒ€ƒ€ƒ€ƒ
摘要:
PROBLEM TO BE SOLVED: To provide a hollow seamless pipe for high-strength spring, in which the generation of decarburizing at the internal surface layer of the pipe is reduced to the utmost, and sufficient fatigue strength can be secured in the spring to be molded by controlling the shape of flaws existing on the internal surface.SOLUTION: A hollow seamless pipe for high-strength spring comprises a steel material whose chemical component composition is properly adjusted. The depth of the whole decarburized layer in an internal surface layer is ≤100 μm, the depth of the flaws existing on the internal surface is ≤40 μm, and the width of the flaw is ≤60 μm. Further, the number density of carbides having a diameter equivalent to circle of ≥500 nm present in the internal surface is ≤1.8×10piece/μm.
摘要:
PROBLEM TO BE SOLVED: To provide a steel wire for a high strength spring which has good shaving properties and good discharging properties of shavings, and also can exhibit good SV treatment properties such that no disconnection is generated during SV treatment, and to provide the high strength spring obtained by using such a steel wire for a high strength spring as a raw material.SOLUTION: A steel wire for a high strength spring is a steel wire after hot rolling, has predetermined chemical component composition, and has structure including mainly pearlite, wherein an average value Pave of grain size number of pearlite nodules satisfies the following formula (1) 6.0≤Pave≤12.0, also the total decarburized depth of a surface layer is 0.20 mm or less, and the total amount of Cr-based alloy carbide is 7.5% or less.
摘要:
High performance high carbon wire with refined inclusions after wire rolling, extremely low wire breakage rates at the time of drawing even in tough applications, and excellent in fatigue characteristics after wire drawing, characterized by having a predetermined composition of ingredients and in that the number ratio of inclusions satisfying (% SiO2)=40 to 95%, (% CaO)=0.5 to 30%, (% Al2O3)=0.5 to 30%, (% MgO)=0.5 to 20%, and (% MnO)=0.5 to 10% and further satisfying (% Na)=0.2 to 7% and (% F)=0.17 to 8% (below, referred to as "inclusions covered due to composition") in the oxide-based nonmetallic inclusions of a short axis of 0.5 mum or more, a long axis of 1.0 mum or more, and a circle equivalent diameter (area converted to diameter) of 1 mum or more which are seen in the L direction cross-section of the wire (below, referred to as "inclusions covered due to size"), that is, the number of inclusions covered due to composition/number of inclusions covered due to size×100, is 80% or more.