A preparation method of glassless grain-oriented silicon steel includes the following operations. During a decarburization annealing, a thickness of an oxide film on a surface of strip is 1.5-2.5 μm; an atomic weight ratio of Si element and Fe element in the oxide film satisfies: Si/(Si+Fe)≥0.76; during a high-temperature annealing, a cooling stage includes sequentially: cooling with an inner cover when a temperature drops from 1200° C. to 500° C.; wherein a protective gas is a mixed gas containing nitrogen and hydrogen, and a volume percentage of the hydrogen in the mixed gas is >3%; cooling with the inner cover when the temperature drops from 500° C. to 200° C.; wherein the protective gas is nitrogen; and cooling in air by removing the inner cover when the temperature is <200° C.

Provided are an anisotropic rare earth sintered magnet having a ThMn.sub.12-type crystal compound as a main phase and exhibits good magnetic characteristics, and a method for producing it. The anisotropic rare earth sintered magnet has a composition of a formula (R.sub.1-aZr.sub.a).sub.v(Fe.sub.1-bCo.sub.b).sub.100-v-w-x-y(M.sup.1.sub.1-cM.sup.2.sub.c).sub.wO.sub.xC.sub.y (where R is one or more kinds selected from rare earth elements and indispensably includes Sm, M.sup.1 is one or more kinds of elements selected from the group consisting of V, Cr, Mn, Ni, Cu, Zn, Ga, Al, and Si, M.sup.2 is one or more kinds of elements selected from the group consisting of Ti, Nb, Mo, Hf, Ta, and W, and v, w, x, y, a, b, and c each satisfy 7≤v≤15 at %, 4≤w≤20 at %, 0.2≤x≤4 at %, 0.2≤y≤2 at %, 0≤a≤0.2, 0≤b≤0.5, and 0≤c≤0.9), which contains a main phase of a ThMn.sub.12-type crystal compound in an amount of 80% by volume or more with the average crystal particle diameter of the main phase being 1 μm or more, which contains an R oxycarbide in the grain boundary area, and which has a density of 7.3 g/cm.sup.3 or more. The production method for the anisotropic rare earth sintered magnet includes grinding an alloy that contains a ThMn.sub.12-type crystal compound phase but does not contain an oxycarbide, then molding it in a mode of pressure powder molding with magnetic field application thereto to give a molded article, and thereafter sintering it at a temperature of 800° C. or higher and 1400° C. or lower to form an oxycarbide in the grain boundary area.

The present invention relates to a high manganese steel for low temperature applications and a method for manufacturing the same. The high manganese steel contains 0.3 wt % to 0.8 wt % of C, 18 wt % to 26 wt % of Mn, 0.01 wt % to 1 wt % of Si, 0.01 wt % to 0.5 wt % of Al, 0.1 wt % or less of Ti (excluding 0%), 1 wt % to 4.5 wt % of Cr, 0.1 wt % to 0.9 wt % of Cu, 0.03 wt % or less of S (excluding 0%), 0.3 wt % or less of P (excluding 0%), 0.001 wt % to 0.03 wt % of N, 0.004 wt % or less of B (excluding 0%), and a remainder of Fe and other inevitable impurities, wherein a microstructure comprises an austenite single phase structure, and an average grain size of the austenite is 50 μm or less.

The present invention relates to a high manganese steel for low temperature applications and a method for manufacturing the same. The high manganese steel contains 0.3 wt % to 0.8 wt % of C, 18 wt % to 26 wt % of Mn, 0.01 wt % to 1 wt % of Si, 0.01 wt % to 0.5 wt % of Al, 0.1 wt % or less of Ti (excluding 0%), 1 wt % to 4.5 wt % of Cr, 0.1 wt % to 0.9 wt % of Cu, 0.03 wt % or less of S (excluding 0%), 0.3 wt % or less of P (excluding 0%), 0.001 wt % to 0.03 wt % of N, 0.004 wt % or less of B (excluding 0%), and a remainder of Fe and other inevitable impurities, wherein a microstructure comprises an austenite single phase structure, and an average grain size of the austenite is 50 μm or less.

A method for manufacturing a watch component is a method for manufacturing a watch component formed of austenitized ferritic stainless steel including a base formed of a ferrite phase and a surfacing layer formed of an austenitized phase in which the ferrite phase is austenitized, the method including a first processing step for forming a hole portion or a recessed portion at a base material formed of ferrite stainless steel, a heat treatment step for performing a nitrogen absorption treatment on the base material to form the surfacing layer at a surface side of the base, and a second processing step for cutting a surfacing layer corresponding to the hole portion or the recessed portion to form the watch component.

Disclosed is a ferritic stainless steel with improved high temperature creep resistance. The disclosed ferritic stainless steel comprises by weight %: 0.005 to 0.03% of C, 0.005 to 0.03% of N, 0.05 to 0.9% of Si, 0.05 to 0.9% of Mn, 14.0 to 19.0% of Cr, 0.1 to 0.6% of Ti, 0.1 to 0.6% of Nb, 0.1 to 0.6% of Cu, 0.01 to 0.04% of P, 0.01% or less (excluding 0) of S, and the balance of iron (Fe) and inevitable impurities, and is characterized by satisfying Expressions (1) and (2) below.

0.5≤Nb/Cu≤3  Expression (1)

20≤[2Nb+Ti]/[C+N]  Expression (2)

wherein Nb, Cu, Ti, C, and N denote contents (wt %) of each element.

Disclosed is a ferritic stainless steel with improved high temperature creep resistance. The disclosed ferritic stainless steel comprises by weight %: 0.005 to 0.03% of C, 0.005 to 0.03% of N, 0.05 to 0.9% of Si, 0.05 to 0.9% of Mn, 14.0 to 19.0% of Cr, 0.1 to 0.6% of Ti, 0.1 to 0.6% of Nb, 0.1 to 0.6% of Cu, 0.01 to 0.04% of P, 0.01% or less (excluding 0) of S, and the balance of iron (Fe) and inevitable impurities, and is characterized by satisfying Expressions (1) and (2) below.

0.5≤Nb/Cu≤3  Expression (1)

20≤[2Nb+Ti]/[C+N]  Expression (2)

wherein Nb, Cu, Ti, C, and N denote contents (wt %) of each element.

A steel composition is provided. The steel composition includes 0.02-0.45 wt. % carbon (C), 0-8 wt. % manganese (Mn), 0-8 wt. % nickel (Ni), 11-17 wt. % chromium (Cr), 1-3 wt. % silicon (Si), and a balance of iron (Fe). The combined concentration of the Mn and Ni is 2-8 wt. %. The steel composition is configured to form a surface oxide layer including oxides of at least one of the Cr or the Si after being subjected to press hardening. Press-hardened steel (PHS) fabricated from the steel composition and a method of fabricating a (PHS) component from the steel composition are also provided.

Provided is a method for manufacturing a grain-oriented electrical steel sheet. A steel slab having a specific chemical composition is heated and hot rolled. A hot-rolled steel sheet thus obtained is subjected to hot band annealing to obtain a cold-rolled steel sheet, which is then subjected to primary recrystallization annealing to obtain a primary recrystallized steel sheet. An annealing separator is applied to the primary recrystallized steel sheet, which is then coiled. The coil is subjected to secondary recrystallization annealing to obtain a grain-oriented electrical steel sheet having an average value of a deviation angle (α.sup.2+β.sup.2).sup.1/2 calculated from a deviation angle α from ideal Goss orientation around an ND rotation axis and a deviation angle β from ideal Goss orientation around a TD rotation axis of 4.5° or less, and an area ratio R.sub.β of crystal grains with β≤0.50° of 15% or less.

Provided is a method for manufacturing a grain-oriented electrical steel sheet. A steel slab having a specific chemical composition is heated and hot rolled. A hot-rolled steel sheet thus obtained is subjected to hot band annealing to obtain a cold-rolled steel sheet, which is then subjected to primary recrystallization annealing to obtain a primary recrystallized steel sheet. An annealing separator is applied to the primary recrystallized steel sheet, which is then coiled. The coil is subjected to secondary recrystallization annealing to obtain a grain-oriented electrical steel sheet having an average value of a deviation angle (α.sup.2+β.sup.2).sup.1/2 calculated from a deviation angle α from ideal Goss orientation around an ND rotation axis and a deviation angle β from ideal Goss orientation around a TD rotation axis of 4.5° or less, and an area ratio R.sub.β of crystal grains with β≤0.50° of 15% or less.