CN103266277B

CN103266277B - High alumina 2205 stainless steel and preparation method thereof

Info

Publication number: CN103266277B
Application number: CN201310236120.7A
Authority: CN
Inventors: 喇培清; 魏玉鹏; 姚亮; 孟倩; 卢学峰; 郭鑫
Original assignee: Lanzhou University of Technology
Current assignee: Lanzhou University of Technology
Priority date: 2013-06-14
Filing date: 2013-06-14
Publication date: 2015-09-30
Anticipated expiration: 2033-06-14
Also published as: CN103266277A

Abstract

High alumina 2205 stainless steel and preparation method thereof, its objective is on the basis of the mechanical property ensureing alloy, improves Alloy Anti oxidation susceptibility; By mass percentage, its composition proportion is: Cr:22%, Ni:5.5%, Mn:1.5%, Si ₃n ₄: 0.45%, Mo:3.2%, C:0.02%, Al:0.5% ~ 2.5%, surplus is Fe; The step of preparation method is: (1), by described composition proportion, based on 2205 stainless steel compositions, preparation is the raw material of 0.5% ~ 2.5% containing Al; (2) melting in a vacuum, gas washing 3 times repeatedly before melting; (3) alloy of melting is carried out cogging hot rolling, 1120 DEG C of shove charges, 1120 DEG C of coggings, air cooling of coming out of the stove, again 1120 DEG C of open rollings, finishing temperature is more than or equal to 950 DEG C, every time volume under pressure 0.1mm, interline of going forward side by side is annealed, then air cooling, and alloy rolling becomes thickness to be the thin slice of 3mm the most at last; (4) workpiece after hot rolling is carried out solution treatment at 1090 DEG C, soaking time is 30min, finally carries out water-cooled and obtains alloy.

Description

High alumina 2205 stainless steel and preparation method thereof

Technical field

The present invention relates to 2205 stainless technologies of preparing.

Background technology

2205 stainless steels have excellent mechanical property and corrosion resistance nature, are purposes one of duplex stainless steels the most widely.Compared with austenitic stainless steel, dual phase steel has good thermal conductivity, lower linear expansivity, at high temperature uses and can prevent from producing thermal crack due to the temperature difference; Compared with ferritic stainless steel, duplex stainless steel has good high temperature creep strength and plasticity, therefore has a good application prospect at high-temperature field.But when 2205 duplex stainless steels are applied to the high-temperature component of less than 315 DEG C, the deficiency of its antioxidant property.On the basis of mechanical property ensureing alloy, in order to improve the high-temperature oxidation resistance of 2205 alloys, in alloy, adding Al element, improving Alloy Anti oxidation susceptibility.

Summary of the invention

The object of the invention is on the basis of the mechanical property ensureing alloy, improve Alloy Anti oxidation susceptibility.

the present invention ishigh alumina 2205 stainless steel and preparation method thereof, high alumina 2205 stainless steel, by mass percentage, its composition proportion is: Cr:22%, Ni:5.5%, Mn:1.5%, Si:0.27%, N:0.18%, Mo:3.2%, C:0.02%, Al:0.5% ~ 2.5%, and surplus is Fe.

The stainless preparation method of high alumina 2205, the steps include:

(1) by the above composition proportion, based on 2205 stainless steel compositions, preparation is the raw material of 0.5% ~ 2.5% containing Al;

(2) melting in a vacuum, gas washing 3 times repeatedly before melting, adopt argon shield in fusion process, electric current is 200A, sample is overturn repeatedly melting 3 times, make its better fusing to reduce defect;

(3) alloy of melting is carried out cogging hot rolling, its technique is as follows: 1120 DEG C of shove charges, 1120 DEG C of coggings, to come out of the stove air cooling, then 1120 DEG C of open rollings, finishing temperature is more than or equal to 950 DEG C, every time volume under pressure 0.1mm, interline of going forward side by side is annealed, then air cooling, and alloy rolling becomes thickness to be the thin slice of 3mm the most at last;

(4) workpiece after hot rolling is carried out solution treatment at 1090 DEG C, soaking time is 30min, finally carries out water-cooled and obtains alloy.

The invention has the beneficial effects as follows, under the maintenance mechanics of material and the prerequisite of general corrosion resistance performance, material at high temperature antioxidant property can be improved.

The present invention is based on 2205 stainless steels, add aluminium in the alloy, by generating fine and close and stable oxide film at alloy surface, carrying heavy alloyed high-temperature oxidation resistance, in heat-resisting alloy steel, obtaining extensive application.But Metal Cr and Cr ₂o ₃difference of thermal expansion coefficients is very large, and Cr ₂o ₃matter is crisp, not easily viscous deformation occurs, and therefore the phenomenon that oxide skin comes off easily occurs under thermal stresses effect.And the Al that Al element is formed at alloy surface ₂o ₃compare Cr ₂o ₃there is higher stability, its hot corrosion resistance can be improved, make it can be on active service under rugged environment.

Alloy of the present invention is after melting, cogging, hot rolling, and final microstructure is the duplex structure of austenite phase+ferritic phase.

Alloy of the present invention and 2205 performance comparison are as following table:

Following stretching experiment carries out on microcomputer controlled electro minor universal testing machine, its ultimate load 100KN, and rate of extension is 0.2 mm/min; GB/T 4334.6-2000 " stainless steel 5% sulfuric acid corrosion test method " is adopted to carry out uniform corrosion experiment to tested alloys.Adopt the high-temperature oxidation resistance of weightening finish method test material, 1000 DEG C, the experiment of 100h constant temperature oxidation are carried out to tested alloys.

As can be seen from the table, the present invention is under the prerequisite maintaining Alloy At Room Temperature mechanics and uniform corrosion performance, and its high-temperature oxidation resistance is improved significantly.

Embodiment

The stainless preparation method of high alumina 2205, the steps include:

the present invention is launched further below by embodiment.

Embodiment 1:

By mass percentage, Cr:22%, Ni:5.5%; Mn:1.5%, Si:0.27%, N:0.18%; Mo:3.2%, C:0.02%, Al:0.5%; surplus is Fe, takes corresponding component, raw material powder is put into planetary ball mill mixing 8 hours; the powder compression mixed is become the cylinder of Φ 20 Χ 50, melting in WS-4 non-consumable vacuum arc melting furnace, gas washing 3 times repeatedly before melting; adopt argon shield in fusion process, electric current is 200A.Sample is overturn repeatedly melting 3 times, make it better melt to reduce defect.After melting completes, sample is cooled to room temperature in water-cooled copper crucible.The alloy of melting is carried out cogging hot rolling, its technique is as follows: 1120 DEG C of shove charge → 1120 DEG C cogging → air cooling → 1120 DEG C open rollings, finish to gauge >=950 DEG C, every time volume under pressure 0.1mm, and repeatedly carrying out process annealing → air cooling, alloy rolling becomes thickness to be the thin slice of 3mm the most at last.Sample after hot rolling is carried out solution treatment at 1090 DEG C, and soaking time is 30min, finally carries out water-cooled and obtains alloy.Performance data: tensile strength sigma _b=780MPa, yield strength σ _0.2=557MPa, unit elongation A=55%, uniform corrosion rate is 24.17 g/ m ²h, oxidation weight gain speed 2.34 g/ m ²h.

Embodiment 2:

By mass percentage, Cr:22%, Ni:5.5%; Mn:1.5%, Si:0.27%, N:0.18%; Mo:3.2%, C:0.02%, Al:1%; surplus is Fe, takes corresponding component, raw material powder is put into planetary ball mill mixing 8 hours; the powder compression mixed is become the cylinder of Φ 20 Χ 50, melting in WS-4 non-consumable vacuum arc melting furnace, gas washing 3 times repeatedly before melting; adopt argon shield in fusion process, electric current is 200A.Sample is overturn repeatedly melting 3 times, make it better melt to reduce defect.After melting completes, sample is cooled to room temperature in water-cooled copper crucible.The alloy of melting is carried out cogging hot rolling, its technique is as follows: 1120 DEG C of shove charge → 1120 DEG C cogging → air cooling → 1120 DEG C open rollings, finish to gauge >=950 DEG C, every time volume under pressure 0.1mm, and repeatedly carrying out process annealing → air cooling, alloy rolling becomes thickness to be the thin slice of 3mm the most at last.Sample after hot rolling is carried out solution treatment at 1090 DEG C, and soaking time is 30min, finally carries out water-cooled and obtains alloy.Performance data: tensile strength sigma _b=750MPa, yield strength σ _0.2=568MPa, unit elongation A=47%, uniform corrosion rate is 18.13 g/ m ²h, oxidation weight gain speed 1.26 g/ m ²h.

Embodiment 3:

By mass percentage, Cr:22%, Ni:5.5%; Mn:1.5%, Si:0.27%, N:0.18%; Mo:3.2%, C:0.02%, Al:1.5%; surplus is Fe, takes corresponding component, raw material powder is put into planetary ball mill mixing 8 hours; the powder compression mixed is become the cylinder of Φ 20 Χ 50, melting in WS-4 non-consumable vacuum arc melting furnace, gas washing 3 times repeatedly before melting; adopt argon shield in fusion process, electric current is 200A.Sample is overturn repeatedly melting 3 times, make it better melt to reduce defect.After melting completes, sample is cooled to room temperature in water-cooled copper crucible.The alloy of melting is carried out cogging hot rolling, its technique is as follows: 1120 DEG C of shove charge → 1120 DEG C cogging → air cooling → 1120 DEG C open rollings, finish to gauge >=950 DEG C, every time volume under pressure 0.1mm, and repeatedly carrying out process annealing → air cooling, alloy rolling becomes thickness to be the thin slice of 3mm the most at last.Sample after hot rolling is carried out solution treatment at 1090 DEG C, and soaking time is 30min, finally carries out water-cooled and obtains alloy.Performance data: tensile strength sigma _b=655MPa, yield strength σ _0.2=542MPa, unit elongation A=30%, uniform corrosion rate is 101.12 g/ m ²h, oxidation weight gain speed 0.34 g/ m ²h.

Claims

1. the stainless preparation method of high alumina 2205, by mass percentage, the composition proportion of its raw material is: Cr:22%, Ni:5.5%, Mn:1.5%, Si:0.27%, N:0.18%, Mo:3.2%, C:0.02%, Al:0.5% ~ 2.5%, and surplus is Fe; The steps include:

(1) by above-described composition proportion, based on 2205 stainless steel compositions, preparation is the raw material of 0.5% ~ 2.5% containing Al;