The present invention provides a flux-cored welding wire comprising a shell having a tubular cavity, which accommodates flux. The shell is made of 400 series stainless steels. The deposited metal formed after the welding using the flux-cored welding wire of the present invention has more uniform chemical compositions. Because the loss of chromium during the transition to the deposited metal is less than 0.1%, recourses is saved and welding cost is reduced. The filling ratio of the flux-cored welding wire of the present invention is 5%-25% (preferably 10%-20%). As a result, not only the stability of the compositions in the flux is increased, but also the disadvantages to the manufacture process caused by high filling ratio are avoided. The flux-cored welding wire of the present invention will not be rusty even after it is exposed to the air for a long time.

Heat treatment equipment for metal plate strips, and a roller quenching flow zone control device for metal plate strips. The device includes a middle water diversion ring sleeve and edge water diversion ring sleeves; the middle water diversion ring sleeve is installed at the middle processing groove in a slit nozzle rear spiral roller and a high-density nozzle rear spiral roller in a high-pressure cooling section of a roller quenching machine; and the edge water diversion ring sleeves are installed at the processing grooves in ¼ and ¾ positions in the width direction of the slit nozzle rear spiral roller in the high-pressure cooling section of the roller quenching machine. This can effectively realize uniform distribution of cooling water on the surface of the plate strip, reduce the phenomenon of local non-uniform cooling caused by siltation of cooling water.

Heat treatment equipment for metal plate strips, and a roller quenching flow zone control device for metal plate strips. The device includes a middle water diversion ring sleeve and edge water diversion ring sleeves; the middle water diversion ring sleeve is installed at the middle processing groove in a slit nozzle rear spiral roller and a high-density nozzle rear spiral roller in a high-pressure cooling section of a roller quenching machine; and the edge water diversion ring sleeves are installed at the processing grooves in ¼ and ¾ positions in the width direction of the slit nozzle rear spiral roller in the high-pressure cooling section of the roller quenching machine. This can effectively realize uniform distribution of cooling water on the surface of the plate strip, reduce the phenomenon of local non-uniform cooling caused by siltation of cooling water.

A martensitic stainless alloy comprising, in percent by weight (wt. %) C >0.50 to 0.60; Si 0.10 to 0.60, Mn 0.40 to 0.80; Cr 13.50 to 14.50; Ni 0 to 1.20; Mo 0.80 to 2.50; N 0.050 to 0.12; Cu 0.10 to 1.50; V max 0.10; S max 0.03; P max 0.03; the balance being Fe an unavoidable impurities.

A martensitic stainless alloy comprising, in percent by weight (wt. %) C >0.50 to 0.60; Si 0.10 to 0.60, Mn 0.40 to 0.80; Cr 13.50 to 14.50; Ni 0 to 1.20; Mo 0.80 to 2.50; N 0.050 to 0.12; Cu 0.10 to 1.50; V max 0.10; S max 0.03; P max 0.03; the balance being Fe an unavoidable impurities.

Provided are a non-quenched and tempered wire rod having excellent drawability and impact toughness suitable for materials for automobiles or mechanical parts and a method of manufacturing the same. According to an embodiment of the present disclosure, the non-quenched and tempered wire rod includes, in percent by weight (wt %), 0.05 to 0.35% of carbon (C), 0.05 to 0.5% of silicon (Si), 0.5 to 2.0% of manganese (Mn), 1.0% or less of chromium (Cr), 0.03% or less of phosphorus (P), 0.03% or less of sulfur (S), 0.01 to 0.07% of soluble aluminum (sol.Al), 0.01% or less of nitrogen (N), at least one of 0.1% or less of niobium (Nb), 0.5% or less of vanadium (V), and 0.1% or less of titanium (Ti), and the remainder of iron (Fe) and inevitable impurities, and includes a ferrite-pearlite layered structure, as a microstructure, in a rolling direction.

Provided are a non-quenched and tempered wire rod having excellent drawability and impact toughness suitable for materials for automobiles or mechanical parts and a method of manufacturing the same. According to an embodiment of the present disclosure, the non-quenched and tempered wire rod includes, in percent by weight (wt %), 0.05 to 0.35% of carbon (C), 0.05 to 0.5% of silicon (Si), 0.5 to 2.0% of manganese (Mn), 1.0% or less of chromium (Cr), 0.03% or less of phosphorus (P), 0.03% or less of sulfur (S), 0.01 to 0.07% of soluble aluminum (sol.Al), 0.01% or less of nitrogen (N), at least one of 0.1% or less of niobium (Nb), 0.5% or less of vanadium (V), and 0.1% or less of titanium (Ti), and the remainder of iron (Fe) and inevitable impurities, and includes a ferrite-pearlite layered structure, as a microstructure, in a rolling direction.

A nickel and chromium alloy having a combined wt. % of nickel and chromium of at least 97 wt. %, wherein the chromium accounts for 33 to 50 wt. % of the alloy. The alloy may be provided in strip form and has adequate ductility for the manufacture of various products, such as sheaths for flux cored welding electrodes. A method of making the alloy strip includes forming a powder charge that is 97 to 100 wt. % of nickel and chromium combined and the chromium accounts for 33 to 50 wt. % of the charge, roll compacting the powder charge to form a green strip, sintering the green strip to form a sintered strip, and cold rolling and annealing the sintered strip to form the alloy strip.

A nickel and chromium alloy having a combined wt. % of nickel and chromium of at least 97 wt. %, wherein the chromium accounts for 33 to 50 wt. % of the alloy. The alloy may be provided in strip form and has adequate ductility for the manufacture of various products, such as sheaths for flux cored welding electrodes. A method of making the alloy strip includes forming a powder charge that is 97 to 100 wt. % of nickel and chromium combined and the chromium accounts for 33 to 50 wt. % of the charge, roll compacting the powder charge to form a green strip, sintering the green strip to form a sintered strip, and cold rolling and annealing the sintered strip to form the alloy strip.

The present disclosure relates to a steel wire rod enabling the omission of softening heat treatment and a method of manufacturing same. An embodiment of the present disclosure provides a steel wire rod enabling the omission of softening heat treatment and a method of manufacturing same, the steel wire rod comprising, in weight %, 0.2-0.45% of C, 0.02-0.4% of Si, 0.3-1.5% of Mn, 0.01-1.5% of Cr, 0.02-0.05% of Al, 0.01-0.5% of Mo, 0.01% or less of N, and the balance Fe and other unavoidable impurities, wherein the microstructure of the steel wire rod is a composite structure of proeutectoid ferrite+perlite as a main phase; the steel wire rod contains 10 area % or less (including 0%) of at least one of bainite or martensite; and the average colony size of the perlite is 5 μm or less.