Abstract: A porcelain enameled steel sheet comprises an aluminum/zinc alloy-plated steel sheet and a porcelain enamel coating layer as the upper most layer of the steel sheet, wherein an interstitial layer having good adhesion to the plating layer and the enamel coating layer is sandwiched between these two layers. The intermediate layer is preferably a member selected from the group consisting of: (1) the surface layer on the aluminum/zinc alloy-plating layer, whose aluminum content is not less than 96% by weight; (2) the surface layer on the aluminum-zinc alloy-plating layer, which comprises aluminum, nickel and not more than 1% by weight of zinc; (3) a coating layer comprising at least one member selected from the group consisting of Ni, Co, Mo, Mn, Ni--P, Ni--Co--P and Co--P; (4) a chromate layer; and (5) a coating layer comprising at least one member selected from the group consisting of zinc phosphate, manganese phosphate and aluminum phosphate.

Abstract: A hot-rolled ferrite steel capable of being used in a hot-rolled annealed condition as a material for a motor vehicle exhaust system including:about 0.02 wt % or less of C,about 0.8 wt % or less of Mn,about 0.015 wt % or less of N,about 0.02 wt % or less of Al,about 0.02 wt % or less of Ti,about 0.02 wt % or less of Zr; the steel further including:about 0.4 to 2 wt % of Si,about 6 to 17 wt % of Cr,about 0.025 to 0.10 wt % of P,about 0.35 to 0.60 wt % of Nb; andthe balance Fe and incidental impurities.The weight percentages of the above components satisfy the following equations (1) and (2):Nb/(C+N).gtoreq.13 (1)11.ltoreq.Cr+3Si+4Nb-50(C+N+P)-Mn-Ni-Co+Mo+Cu.ltoreq.16.5 (2),such that a low-cost ferritic steel is produced which, after conventional hot rolling, exhibits characteristics well-suited for motor vehicle exhaust systems such as high workability, high heat resistance and good manufacturability.

Abstract: A high strength steel sheet adapted for press forming and method producing the same. The steel sheet containing by weight C: 0.01-0.1%, Si: 0.1-1.2%, Mn: not more than 3.0%, Ti:a value of (Ti%-1.5S%-3.43N%)/C% being 4-12, B: 0.0005-0.005%, Al: not more than 0.1%, P: not more than 0.1%, S: not more than 0.02%, N: not more than 0.05%. The method for producing the steel sheet wherein a steel slab containing the above mentioned component composition is heated and hot rolled in a temperature range of 1100-1280.degree. C. to provide a hot rolled sheet. The hot rolled sheet may be is subjected to cold rolling and annealing to provide a cold rolled sheet.

Abstract: A method of producing a ferritic stainless steel strip having reduced intra-face anisotropy as well as excellent r value and anti-ridging characteristics. The method involves subjecting a ferritic stainless steel slab to a hot rolling step including rough rolling having at least one rough rolling pass and a finish rolling having at least one finish rolling pass, followed by a hot-rolled sheet annealing, pickling, cold rolling and finish annealing. At least one of the passes in the rough rolling is conducted with the rolling temperature between about 970.degree. C. to about 1150.degree. C., the friction coefficient between the rolls and the rolled material of about 0.3 or less, and the rolling reduction ratio between about 40 to about 75%.

Abstract: A ferritic stainless steel exhibiting excellent atmospheric corrosion resistance and crevice corrosion resistance can be provided by positively adding P thereto and by adequately adjusting Ca and Al. The ferritic stainless steel according to the present invention essentially consists of, in weight percentages,C: about 0.05% or lessSi: about 1.0% or lessCr: about 11% or more and less than about 20%Mn: about 1.0% or lessN: about 0.10% or lessS: about 0.03% or lessCa: about 5 ppm or more and about 50 ppm or lessAl: about 0.5% or lessP: more than about 0.04% and about 0.20% or lessand the balance being iron and incidental impurities. The stainless steel according to the present invention may also contain at least one element selected from a group (1) consisting of about 6% or less of Mo, group (2) consisting of about 1.0% or less of Cu, about 3% or less of Ni and about 3% or less of Co, or group (3) consisting of about 1.0% or less of Ti, about 1.0% or less of Nb, about 1.0% or less of V, about 1.

Abstract: High Cr content, P added ferritic stainless steel containing, in % by weight, C: up to 0.02%, Si: up to 1.0%, Mn: up to 1.0%, S: up to 0.03%, Cr: from more than 20% to 40%, N: up to 0.015%, Al: up to 0.5%, and P: from more than 0.06% to 0.20%, the balance being Fe and incidental impurities, is improved in atmospheric corrosion resistance and rust prevention. The stainless steel may further contain at least one element selected from the following groups: (1) Mo: up to 4.0%; (2) one or more elements of Ti: up to 1.0%, Nb: up to 1.0%, Ta: up to 1.0%, V: up to 1.0%, W: up to 1.0%, Zr: up to 1.0%, and B: up to 0.01%; and (3) one or more elements of Cu: up to 1.0%, Ni: up to 5.0%, and Co: up to 1.0%.

Abstract: A ferrite steel suitable for use as the material of a part which is used at high and which is required to have high toughness at weld heat affected zones. The ferrite steel has a composition which contains C: not more than 0.02 wt %, Si: not more than 2.0 wt %, Mn: not more than 1.0 wt %, Cr: not less than 6.0 wt % but not more than 23.0 wt %, Ni: not more than 1.0 wt %, Nb: not less than 0.4 wt % but not more than 0.65 wt %, Co: not less than 0.01 wt % but not more than 2.0 wt %, Al: not more than 0.5 wt %, N: not more than 0.03 wt % and the balance substantially Fe and incidental inclusions.

Abstract: A galvanized steel sheet is provided which has a tensile strength of not less than 80 kgf/mm.sup.2 and a yield ratio of not more than 60%, and which is applicable to members of an automobile body, particularly those requiring strength.By appropriately controlling the amounts of components, such as C, Mn, Nb, Ti and B, the structure of the steel sheet is formed into a dual-phase structure having a second phase strucutre. The steel sheet is recrystallization-annealed, galvanized while it is maintained at a temperature range near 500.degree. C., and then is cooled. By controlling the rate of cooling the steel sheet, the second phase structure generated is prevented from hardening more than necessary. A galvanized high-strength steel sheet is obtained which has a low yield ratio and excellent stretch-flanging properties.

Abstract: A graphite precipitated hot-rolled steel plate having excellent bending workability and hardenability, the graphite precipitated hot-rolled steel plate comprising: 0.1 to 1.0% (by weight percent) C; 0.05 to 1.0% (by weight percent) Mn; 3 to 50 ppm B; 200 ppm or less N the quantity of which is three times or more the quantity of B; and a balance of Fe and unavoidable impurities, wherein graphite the diameter of which is 5 .mu.m or less is precipitated in such a manner that distance between graphite particles is at a distance of 5 .mu.m or longer.

Abstract: A high tensile cold rolled steel sheet improved in stretch flanging property, containing 0.03% to 0.15% by weight of C, 0.05% or less by weight of Si, 0.5% to 1.2% by weight of Mn, 0.005% to 0.045% by weight of Nb, and 0.10% or less by weight of Al, the remainder being iron and unavoidable impurities, and the steel sheet having a uniform and fine recrystallized ferrite structure having a mean grain diameter of 20 .mu.m or less and an area fraction of 95% or more having improving ductility and a process for its preparation.

Abstract: A flexible hot rolled steel sheet having an improved deep drawability comprises not more than 0.10 wt % of C, less than 0.20 wt % of Mn, 0.10-2.0 wt % of Cr, 0.002-0.100 wt % of Al, and the balance being Fe and inevitable impurities or further contains particular amounts of at least one of Ti, Nb and Zr and/or B. Such a hot rolled steel sheet has a tensile strength of not more than 35 kgf/mm.sup.2 and a total elongation of not less than 50%.

Abstract: A control method for controlling the screwing down pressure provided in a reeling mill where the reels are controlled by a combination of signals continuously monitored by a computer. The signals include the temperature of the pipe entering the reeling mill, the voltage and current supplied to the reeling motor and the speed of the reeling motor. A calculation is then performed which gives the actual reduction of wall thickness based upon a predetermined relationship of the temperature of the pipe entering the reeling mill and the torque of the rolling motor. The torque is calculated based upon the speed, current and voltage of the rolling motor. The pressure supplied to the rolling reels is then altered based on this signal.