CN105714205A - Steel alloy of low alloy steel - Google Patents
Steel alloy of low alloy steel Download PDFInfo
- Publication number
- CN105714205A CN105714205A CN201410723790.6A CN201410723790A CN105714205A CN 105714205 A CN105714205 A CN 105714205A CN 201410723790 A CN201410723790 A CN 201410723790A CN 105714205 A CN105714205 A CN 105714205A
- Authority
- CN
- China
- Prior art keywords
- steel
- alloy
- low
- content
- highest
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Abstract
The invention relates to a steel alloy of low alloy steel for high-strength weldable hot-rolled seamless steel tubing, especially structural tubing. The steel alloy comprises the following chemical components, by mass, 0.12 to 0.21% of C, 0.3 to 0.5% of Si, 1.610 to 1.8% of Mn, no more than 0.04% of P, no more than 0.005% of S, 0.40 to 0.8% of Cr, 0.60 to 0.90% of Mo, 0.13 to 0.17% of V, 0.55 to 1.4% of W and 0.015 to 0.03% of N, with the balance being Fe and impurities produced in smelting. One or more elements selected from a group consisting of Al and Ti are optionally added so as to allow the contents of Al and Ti in the alloy to be no more than 0.01% and 0.03% respectively on the premise that the ratio of V/N is 4 to 12 and the content of Ni in the steel is no more than 0.40%.
Description
Technical field
The present invention relates to the steel alloy of low-alloy steel for manufacturing high-strength seamless steel pipe material.
Background technology
The invention particularly relates to tubing, it can also have non-circular cross section and as the structural tube welded steel structure for extra-high load, for instance in the structure of crane, bridge, boats and ships, lowering or hoisting gear and load-carrying vehicle.
Such tubing except circular cross-section, also can as requested with use field and have such as square, rectangle or also have polygonal cross section.
Such as, DE19942641A1 the steel alloy of this kind of steel tubing is become known for.This conventional steel alloy is except adding chromium, molybdenum and vanadium on a small quantity, as the feature of low-alloy steel, when giving up nickel, is also added with the tungsten of 0.30-1.00%.
By giving up the nickel Qiang Zhiyaoqiud in other cases or being restricted to low concentration to major general's nickel content, it is intended to for suppressing tacky oxide skin and thus improving surface quality, carry out Pilger hot rolling tubing (WarmpilgernvonRohren) period particularly in by this kind of steel, and avoid the cutting post-treatment to surface of high cost required in other cases.
Structural tube for above-mentioned application bears the very high loads requirement in intensity and toughness under being low to moderate most the low temperature of-40 DEG C.
In order to reach required performance, described tubing must carry out modifier treatment after hot rolling adopt by DE19942641A1 with the known steel of FGS70 form, reach all minimums that can be required for yield limit, hot strength, fracture elongation and notch shock.But, the requirement of the structural tube for above-mentioned application is being improved constantly in recent years always so that have increasing need for that there is structural tube claimed below now:
● yield limit Rp0.2 is minimum: 960MPa
● hot strength Rm:980-1150MPa
● notch shock energy Av (longitudinal direction): be 27J at-40 DEG C
● ensure general solderability
● low or limited Ni content.
The intensity required when the hot worked seamless tubular goods for described application has sufficiently ductile improves, it is necessary to the alloy scheme (Legierungskonzepte) that research and development make new advances.Particularly when yield limit ranges for about 1000MPa, traditional alloy scheme can not reach enough toughness at low temperatures.
It is reduce crystallite dimension that known increase intensity leads the mechanism also causing toughness increase simultaneously.This can such as by adding to nickel or molybdenum in alloy and related to this reducing conversion temperature and reduce crystallite dimension.
But, these alloy schemes cause the increase of carbon equivalent and related to this cause poor solderability.Additionally, nickel and molybdenum make cost of alloy significantly raise and nickel also makes the surface quality of hot rolling tubing deteriorate.
But, improve carbon content and can cause the deterioration of toughness and significantly improving of carbon equivalent with the obvious probability increasing intensity.
Vanadium is equally used for improving intensity.The program is hardened and the precipitation of superfine vanadium carbide based on the mixed crystal of vanadium during temper.But, adopt above-mentioned alloying scheme can not meet required performance.Reduce crystallite dimension to carry out also by thermo-mechanical processi in principle to improve mechanical performance.But, when hot-working seamless tubular goods, specific temperature progress does not allow the reduction of deformation temperature so that can use the known arrangement for thermo-mechanical processi.High request required up to now can only adopt high-alloy steel to be achieved, and described high-alloy steel does not have due to its high cost or only has low market acceptance.
Summary of the invention
It is an object of the invention to provide the inexpensive steels alloy of the low-alloy steel of a kind of welding seamless steel pipe material (especially structural tube) for manufacturing high intensity, described low-alloy steel reliably meets the minimum requirements in yield limit, hot strength and notch shock energy, and ensures good solderability and cause visually flawless surface when hot rolling.
For reaching above-mentioned purpose, the present invention adopts the following technical scheme that
The steel alloy of a kind of low-alloy steel, it is characterised in that it has following chemical composition, in quality %:
0.12-0.21%C；0.3-0.5%Si；1.610-1.8%Mn；The highest 0.04%P；The highest 0.005%S；0.40-0.8%Cr；0.60-0.90%Mo；0.13-0.17%V；0.55-1.4%W；0.015-0.03%N
The ferrum of surplus and the impurity caused by smelting, be optionally added into one or more elements in Al and Ti so that described in be optionally added into the element of alloy there is following content:
The highest 0.01%Al；The highest 0.03%Ti, premise is, the ratio of V/N is that the Ni content of 4-12 and described steel is less than 0.40%.
The steel alloy of the present invention is to continue to be undertaken by the research and development of the fine grained structural steel adding tungsten in the alloy known for DE19942641A1.
Unknown by experience known up to now, tungsten has adverse effect for solderability.But, root is it was found that raise to be only be up to about 900MPa by carrying out the accessible maximum yield limit of alloying with tungsten.Further raise is only impossible by raising W content.Therefore, it has proved that favourable W content is 0.55-1.4%%, it is preferable that 1-1.2%.
The test carried out in process of the present invention shows astoundingly, when only adding alloying element such as Cr and Mo with the amount of somewhat higher compared with known steel alloy, keeping specific V/N ratio to obtain significant intensity to improve, the notch shock simultaneously still keeping required can for 27J at-40 DEG C.However, it has proven that in order to reach specific " fundamental strength ", Cr, Mo and W interpolation total amount should be at least 1.7 weight %.
The present invention includes by carrying out recrystallization final temperature is increased in microalloying the innovative scheme being significantly higher than final rolling temperature with vanadium and nitrogen targetedly.Based on the calculation of thermodynamics of wide scope, the ratio of the content of V and N is necessary for 4-12, in order to reach desired effect.
It is said that in general, the nitrogen of the dissolving of high-load (Stickstoff) is considered for toughness to be disadvantageous.But, by being appropriately selected V/N ratio within the scope of 4-12, it is possible to the content of the nitrogen of dissolving is reduced to minimum, and the vanadium carbonitride formed has described Grain Refinement Effect by thermo-mechanical processi simultaneously.Additionally, the alloy with abnormal high nitrogen content (harmless because forming vanadium-carbonitride or even for grain refinement) additionally advantageously make need not in the degassed process of the costliness within the scope of second metallurgy.
In the alloying aspects of the present invention, depending on the needs, one or more following alloying elements are optionally added in alloy by design: Al and Ti.Such as, these need to be drawn by the different wall thickness of tubing to be rolled, this wall thickness may be at adding described element lower than 10mm to higher than making to require over alloying when in the scope of 80mm and particularly in relatively thick, in order to realizes required performance by grain refinement.
Optimum cost/profit relationship in view of described alloying scheme, it has proved that following content is advantageous for: the Al of the highest 0.01%, the Ti of the highest 0.03%.The Ni content of the highest 0.30% is of a sufficiently low, in order to produce enough good surface quality in the continuous tubulation method (Rohrkontiverfahren) being mainly used in such steel material.
The optimization formula of the present invention is:
It has following chemical composition, in quality %:
0.2%C；0.4%Si；1.65%Mn；0.014%P；0.004%S；0.7%Cr；0.8%Mo；0.15%V；0.6%W；0.017%N；0.005%Al；0.018%Ni；And V/N=8.03.
Claims (4)
1. the steel alloy of a low-alloy steel, it is characterised in that it has following chemical composition, in quality %: 0.12-0.21%C；0.3-0.5%Si；1.610-1.8%Mn；The highest 0.04%P；The highest 0.005%S；0.40-0.8%Cr；0.60-0.90%Mo；0.13-0.17%V；0.55-1.4%W；0.015-0.03%N
The ferrum of surplus and the impurity caused by smelting, be optionally added into one or more elements in Al and Ti so that described in be optionally added into the element of alloy there is following content:
The highest 0.01%Al；The highest 0.03%Ti, premise is, the ratio of V/N is that the Ni content of 4-12 and described steel is less than 0.40%.
2. steel alloy according to claim 1, it is characterised in that it has following chemical composition, in quality %: 0.2%C；0.4%Si；1.65%Mn；0.014%P；0.004%S；0.7%Cr；0.8%Mo；0.15%V；0.6%W；0.017%N；0.005%Al；0.018%Ni；And V/N=8.03.
3. steel alloy according to claim 1, it is characterised in that W content is 1-1.2%.
4. steel alloy according to claim 1, Cr, Mo and W interpolation total amount be at least 1.7 weight %.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410723790.6A CN105714205A (en) | 2014-12-04 | 2014-12-04 | Steel alloy of low alloy steel |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410723790.6A CN105714205A (en) | 2014-12-04 | 2014-12-04 | Steel alloy of low alloy steel |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN105714205A true CN105714205A (en) | 2016-06-29 |
Family
ID=56146858
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201410723790.6A Pending CN105714205A (en) | 2014-12-04 | 2014-12-04 | Steel alloy of low alloy steel |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN105714205A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110669981A (en) * | 2019-10-02 | 2020-01-10 | 江苏省沙钢钢铁研究院有限公司 | Vanadium-boron composite microalloyed cord steel wire rod and production method thereof |
-
2014
- 2014-12-04 CN CN201410723790.6A patent/CN105714205A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110669981A (en) * | 2019-10-02 | 2020-01-10 | 江苏省沙钢钢铁研究院有限公司 | Vanadium-boron composite microalloyed cord steel wire rod and production method thereof |
| CN110669981B (en) * | 2019-10-02 | 2021-07-16 | 江苏省沙钢钢铁研究院有限公司 | Vanadium-boron composite microalloyed cord steel wire rod and production method thereof |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101724777B (en) | Hot rolled wheel rim steel plate with tensile strength of 550MPa grade and manufacturing method thereof | |
| EP2617852B1 (en) | High-strength hot-rolled steel sheet having excellent bending workability and method for producing same | |
| CN105408512B (en) | High-strength steel material for oil well use, and oil well pipe | |
| CN103952643B (en) | Low-yield ratio steel plate with yield strength of 690MPa and preparation method of steel plate | |
| CN105624585B (en) | A kind of floating LNG pipelines X80Q hot-rolled thick planks and its production method | |
| CN101353766B (en) | Grooving corrosion resistant high strength steel for ERW soldering sleeve, sleeve and production method | |
| WO2016119500A1 (en) | Steel plate having high crack-arresting performance, and manufacturing method thereof | |
| JP5187003B2 (en) | High strength steel material excellent in formability and fatigue resistance and method for producing the same | |
| CN107208212A (en) | Heavy wall high-tenacity high-strength steel plate and its manufacture method | |
| EP2804962A1 (en) | An austenitic stainless steel product and a method for manufacturing same | |
| CN105586529B (en) | A kind of 890MPa grade high-strengths steel, steel pipe and its manufacture method | |
| EP3719162A1 (en) | High strength steel material having excellent hydrogen-induced cracking resistance and low-temperature impact toughness and manufacturing method therefor | |
| CN111356780A (en) | Profiled bar having a thickness of at least 100mm and method for producing same | |
| CN102443687A (en) | Microstructure component controlling method for raising yield ratio of fine grain reinforced bar | |
| CN103993245A (en) | Low-carbon equivalent high-strength hot-rolled seamless pipeline tube and manufacturing method thereof | |
| JP2015193887A (en) | Low yield ratio high strength spiral steel pipe pile and manufacturing method therefor | |
| JP6056236B2 (en) | Method for producing high-tensile steel sheet having excellent weldability and delayed fracture resistance and tensile strength of 780 MPa or more | |
| KR101971772B1 (en) | Method of manufacturing steel plate for high-heat input welding | |
| WO2018115925A1 (en) | Steel section having a thickness of at least 100mm and method of manufacturing the same | |
| JP2006241551A (en) | Thick steel plate having excellent weldability and low temperature toughness | |
| CN101952472B (en) | Steel alloy for a low alloy steel for producing high-tensile seamless steel tubing | |
| CN1715435A (en) | Method for producing X80 pipeline steel having anti-HIC property and its hot-rolled plate | |
| CN102534431B (en) | Ti-containing medium-carbon steel, as well as method for continuous casting and continuous rolling by adopting sheet billets | |
| CN105714205A (en) | Steel alloy of low alloy steel | |
| WO2016143345A1 (en) | High-strength thick steel sheet and method for manufacturing same |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Application publication date: 20160629 |
|
| WD01 | Invention patent application deemed withdrawn after publication |