CN109266973B - Fe-Mn-Si-Ni-C series elastic-plastic damping steel and manufacturing method and application thereof - Google Patents
Fe-Mn-Si-Ni-C series elastic-plastic damping steel and manufacturing method and application thereof Download PDFInfo
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- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D2211/00—Microstructure comprising significant phases
- C21D2211/001—Austenite
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- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D2211/00—Microstructure comprising significant phases
- C21D2211/008—Martensite
Abstract
The invention relates to Fe-Mn-Si-Ni-C series elastic-plastic damping steel and a preparation method and application thereof, wherein the steel comprises the following chemical components in percentage by mass: 20.0% to 34.0% of Mn, 3.5% to 6.0% of Si, 0.1% to 5.0% of Ni, 0.005% to 0.15% of C, 0.02% to 0.02% of P, 0.03% to 0.03% of S, 0.02% to N and the balance of Fe and inevitable impurity elements, wherein the mass percentages of the Mn, the Ni and the C elements also need to satisfy the following relations: mn +1.6Ni +52C is more than or equal to 32 percent and Mn +2Ni is less than or equal to 37 percent. The elastic-plastic damping steel is prepared by the production process flow of casting, hot rolling and annealing after hot rolling or the production process flow of casting, hot rolling, pickling, cold rolling and annealing after cold rolling. The yield strength of the high-performance elastic-plastic damping steel is less than 360 MPa; under the condition of cyclic tensile-compression loading, when the strain amplitude, the strain ratio and the loading frequency are respectively 1%, -1.0 and 0.1-0.2 Hz, the stress amplitude is less than 530MPa, and the room-temperature fatigue life of the steel plate is more than 2000 weeks.
Description
Technical Field
The invention belongs to the technical field of steel materials, and particularly relates to Fe-Mn-Si-Ni-C series elastic-plastic damping steel and a manufacturing method and application thereof.
Background
Large-scale earthquakes and external long-time and long-period vibration cause great damage to high-rise buildings and structures. The elastic-plastic steel shock absorption damper placed in the building and the structure can effectively absorb external shock energy, and the damage of the building and the structure is reduced to the minimum degree. The elastic-plastic steel damper absorbs the vibration energy by leading the steel material to yield and then elastic-plastic hysteresis deformation under the action of external reciprocating vibration. Therefore, a steel material for a damper (hereinafter referred to as "elasto-plastic damping steel") is required to have the following properties: low yield strength, stable hysteresis characteristic, full hysteresis curve and good low cycle fatigue performance.
The elastic-plastic damping steel commonly used at present is mild steel and low-yield-point carbon steel. The damping steel mainly used in China comprises DT4 industrial pure iron, Q235 steel and the like; internationally, Nissan iron and JFE iron and steel companies in Japan both develop shock-absorbing low-yield-point steels (such as BT-LYP100, JFE-LY225 and the like) with yield strengths of 100-225 MPa. The fatigue life of such materials tends to be low because cracks are generally induced, propagated earlier from stress concentration and strain incompatibility (e.g., dislocation slip bands, grain boundaries, and ferrite/cementite phase boundaries) and dislocation cell structures, and ultimately fatigue failure of the material under alternating loading.
The Fe-Mn-Si-Al alloy in a certain component range has lower yield strength, good low-cycle fatigue performance and welding performance, and is ideal elastoplastic damping steel. However, the inventor finds that the damping steel grade is rich in Al element (the steel grade is developed by Al alloying as an important technical path), which brings the following main technical difficulties to the smelting and casting production process of the steel: the viscosity of the molten steel is obviously increased, and the fluidity of the molten steel is deteriorated; the control difficulty of impurities and smelting components in steel is increased; when continuous casting is employed, a reaction between steel and mold flux easily occurs. The above technical problems tend to reduce the quality of the damping steel and greatly increase the production cost.
Disclosure of Invention
Based on the current state of the prior art, the development of high-performance damping steel without Al alloy as an important technical approach is urgently needed.
The invention provides Fe-Mn-Si-Ni-C series elastic-plastic damping steel in a first aspect, provides a manufacturing method of the Fe-Mn-Si-Ni-C series elastic-plastic damping steel in a second aspect, and provides application of the Fe-Mn-Si-Ni-C series elastic-plastic damping steel in a third aspect.
The purpose of the invention can be realized by the following technical scheme:
the first aspect of the invention provides Fe-Mn-Si-Ni-C series elastic-plastic damping steel:
the Fe-Mn-Si-Ni-C series elastic-plastic damping steel comprises the following chemical components in percentage by mass: 20.0% to 34.0% of Mn, 3.5% to 6.0% of Si, 0.1% to 5.0% of Ni, 0.005% to 0.15% of C, 0.02% to 0.02% of P, 0.03% to 0.03% of S, 0.02% to N and the balance of Fe and inevitable impurity elements, wherein the mass percentages of the Mn, the Ni and the C elements also need to satisfy the following relations: mn +1.6Ni +52C is more than or equal to 32 percent and Mn +2Ni is less than or equal to 37 percent.
Preferably, the chemical components of the Fe-Mn-Si-Ni-C series elastic-plastic damping steel comprise the following Si by mass percent: 4.0 to 5.0 percent.
Preferably, the mass percentages of the chemical components are as follows: mn is more than or equal to 21.4 percent and less than or equal to 33.4 percent, Si is more than or equal to 3.92 percent and less than or equal to 5.88 percent, Ni is more than or equal to 0.52 percent and less than or equal to 4.92 percent, C is more than or equal to 0.012 percent and less than or equal to 0.141 percent, P is less than or equal to 0.02 percent, S is less than or equal to 0.03 percent, N is less than or equal to 0.01 percent, and the balance is Fe and inevitable impurity elements, wherein the mass percentage of the Mn, the Ni and: mn +1.6Ni +52C is more than or equal to 32.7 percent and Mn +2Ni is less than or equal to 36.8 percent.
Further preferably, the chemical components are as follows by mass percent: mn is more than or equal to 28 percent and less than or equal to 32 percent, Si is more than or equal to 4 percent and less than or equal to 5 percent, Ni is more than or equal to 2.5 percent and less than or equal to 3 percent, C is more than or equal to 0.06 percent and less than or equal to 0.11 percent, P is less than or equal to 0.01 percent, S is less than or equal to 0.02 percent, N is less than or equal to 0.01 percent, and the balance of Fe and inevitable impurity elements, wherein the mass percentages of Mn, Ni and C elements: mn +1.6Ni +52C is more than or equal to 38 percent and Mn +2Ni is less than or equal to 37 percent.
Further, the microstructure of the Fe-Mn-Si-Ni-C series elastic-plastic damping steel is austenite and martensite with the volume fraction not more than 10%.
Further, the yield strength (or the specified non-proportional elongation strength R) of the Fe-Mn-Si-Ni-C system elasto-plastic damping steelp0.2) Less than 360 MPa; under the condition of cyclic tensile-compression loading, when the strain amplitude, the strain ratio and the loading frequency are respectively 1%, -1.0 and 0.1-0.2 Hz, the stress amplitude is less than 530MPa, and the room-temperature fatigue life of the steel plate is more than 2000 weeks.
In the composition design of the Fe-Mn-Si-Ni-C system elasto-plastic damping steel of the present invention, the effects of the respective components are as follows.
Mn: mn is the main alloying element in the present invention. Mn increases austenite stability and promotes austenite formation. Mn can effectively regulate the austenite stacking fault energy and the martensite phase transformation point, thereby inhibiting the generation of alpha' martensite and excessive heat-induced martensite and promoting the generation of stress/strain-induced martensite. When the content of Mn is less than 20.0%, alpha' martensite and excessive heat-induced martensite are easily formed in an austenite matrix, so that the low cycle fatigue life of the alloy is reduced; when the Mn content is higher than 34.0%, the austenite only forms deformation twin crystals under stress/strain instead of martensite, and the low cycle fatigue life of the alloy is also remarkably reduced. Therefore, the Mn content is controlled to be 20.0-34.0 percent.
Si: si is the main alloying element in the present invention. Si lowers the austenite stacking fault energy and antiferromagnetic transition temperature, facilitating the generation of stress/strain induced fine sheet martensite with single-morphic crystallographic characteristics. In addition, Si plays a role in solid solution strengthening and adjusts the lattice correspondence between austenite and martensite, and the two promote the transformation from martensite to austenite, thereby being beneficial to improving the low cycle fatigue life of the alloy. When the Si content is less than 3.5%, the stacking fault probability of austenite is relatively low, which is not beneficial to the occurrence of reversible phase transformation between austenite and martensite; when the Si content is more than 6.0%, not only an iron-silicon intermediate phase is formed in the original structure of the alloy, but also the volume content of martensite generated by internal stress/strain induction of the alloy under the action of alternating load is increased too fast and the interaction between the martensite occurs, which are also unfavorable for the occurrence of reversible transformation between austenite and martensite and the low cycle fatigue life of the alloy is reduced. Therefore, the present invention limits the Si content to 3.5% to 6.0%, preferably 4.0% to 5.0%.
Ni: ni is the main alloying element in the present invention. On one hand, the addition of a proper amount of Ni element can adjust (reduce) the martensite phase transformation point and inhibit the generation of excessive heat induced martensite; and the proper amount of Ni element is beneficial to inhibiting the volume content of the internal stress/strain-induced martensite of the alloy from excessively and rapidly increasing under the action of alternating load and the interaction between the martensite, thereby improving the reversibility of austenite and martensite transformation and the low-cycle fatigue life of the alloy. When the Ni content is less than 0.1%, the above-mentioned effects due to the addition of Ni element are not significant. On the other hand, the Ni element increases the stacking fault energy of austenite in steel, and the excessive addition of the Ni element suppresses the occurrence of stress/strain-induced martensite transformation and promotes the formation of deformation twins, thereby reducing the low cycle fatigue life of the alloy. Further, Ni is a noble metal element, and addition of excessive Ni causes a significant increase in raw material cost. The invention limits the Ni content to be 0.1-5.0%.
C: c is an important additional element in the present invention. On one hand, C plays a role in solid solution strengthening, can obviously improve the resistance of plastic deformation of the alloy caused by dislocation slip, promotes reversible transformation between austenite and martensite, and improves the low-cycle fatigue performance of the alloy. In addition, the element C can be used to adjust (lower) the martensite transformation point and suppress the formation of excessive thermally induced martensite. When the C content is less than 0.005%, the above-mentioned effects do not appear. On the other hand, C atoms tend to segregate at the austenite/martensite phase interface. When the content of C is more than 0.15%, segregation of C atoms at the phase interface significantly suppresses the movement of the two-phase interface and occurrence of reversible phase transformation, thereby reducing the low cycle fatigue life of the alloy. Therefore, the content of C is controlled to be 0.005-0.15 percent.
In the invention, the mass percentages of Mn, Ni and C elements also need to satisfy the following relations: mn +1.6Ni +52C is more than or equal to 32 percent and Mn +2Ni is less than or equal to 37 percent. When Mn +2Ni is more than 37%, the austenite stacking fault energy may be high, and stress/strain-induced martensite transformation is easily suppressed. When the Mn +1.6Ni +52C content is less than 32%, the original structure of the alloy has a large content of heat-induced martensite, the volume content of the internal stress/strain-induced martensite of the alloy is increased too fast under the action of alternating load, and the reversible transformation between austenite and martensite is inhibited by the interaction of the martensite, so that the low-cycle fatigue life of the alloy is obviously reduced.
The invention defines the original matrix microstructure of the elastic-plastic damping steel as austenite and martensite (formed by thermal induction) with the volume fraction not more than 10%, and aims to promote the generation of stress/strain-induced lamellar martensite with single variant crystallography characteristics under the action of alternating load and avoid strong interaction between the thermal-induced martensite in the original matrix microstructure and the martensite formed by stress/strain induction, thereby promoting the reversible transformation between the austenite and the martensite and improving the low-cycle fatigue life of the alloy.
P: p is a solid solution strengthening element; however, P increases the cold brittleness of the steel, decreases the plasticity of the steel, and deteriorates the weldability. Therefore, the P content in the steel is limited to be less than or equal to 0.02 percent.
S: s causes hot shortness of the steel, reduces ductility and toughness of the steel, and deteriorates weldability. Therefore, the S content is limited to 0.03% or less.
N: n is a solid solution strengthening element, but can significantly reduce the plasticity, toughness and welding performance of the alloy. Therefore, the N content is limited to 0.02% or less.
In the invention, under the premise of not changing the microstructure and the deformation mechanism of the elastic-plastic damping steel (namely under the action of cyclic load, the alloy generates reversible phase transformation between austenite and martensite), the components of the elastic-plastic damping steel can also contain a small amount of Cu and Cr elements, and the mass percentage of the contents of the Cu and Cr elements is not more than 1.0 percent.
In the invention, on the premise of not changing the microstructure and the deformation mechanism of the elastic-plastic damping steel (namely, under the action of cyclic load, the alloy generates reversible phase transformation between austenite and martensite), Al can be used as a deoxidizer or non-main element is added into the alloy, but the mass percentage of the Al element content is not more than 1.0%.
The second aspect of the present invention provides a method for producing the above-mentioned Fe-Mn-Si-Ni-C system elasto-plastic damping steel:
the first preparation method of the Fe-Mn-Si-Ni-C series elasto-plastic damping steel comprises the following steps:
1) smelting and casting according to the following component proportion to obtain a casting blank,
the mass percentage of the chemical components is as follows: 20.0% to 34.0% of Mn, 3.5% to 6.0% of Si, 0.1% to 5.0% of Ni, 0.005% to 0.15% of C, 0.02% to 0.02% of P, 0.03% to 0.03% of S, 0.02% to N and the balance of Fe and inevitable impurity elements, wherein the mass percentages of the Mn, the Ni and the C elements also need to satisfy the following relations: mn +1.6Ni +52C is more than or equal to 32 percent and Mn +2Ni is less than or equal to 37 percent;
2) hot rolling
Heating the casting blank at 1000-1250 ℃, wherein the heat preservation time is 0.5-3 h, the hot rolling casting blank is a hot rolled plate, the hot rolling deformation is more than or equal to 25%, and the final rolling temperature is more than or equal to 800 ℃;
3) post hot rolling annealing
Heating the hot rolled plate to the soaking temperature of 650-1100 ℃ and soaking time of 0.5-10 h; and cooling the steel plate to room temperature after the annealing is finished.
The first preparation method of the Fe-Mn-Si-Ni-C series elasto-plastic damping steel has the following design reasons:
(1) hot rolling process
The heating temperature is 1000-1250 ℃. When the heating temperature exceeds 1250 ℃, the cast plate blank is over-burnt, and the grain structure in the plate blank is coarse, so that the hot working performance is reduced; when the heating temperature is lower than 1000 ℃, after the plate blank is descaled by high-pressure water and is initially rolled, the finish rolling temperature is too low, so that the deformation resistance of the plate blank is too high, and the hot-rolled steel plate which has no surface defects and has a specified thickness is difficult to manufacture.
The heat preservation time is 0.5-3 h during hot rolling, and the heat preservation time exceeds 3h, so that the grain structure in the plate blank is coarse; the heat preservation time is less than 0.5h, and the internal temperature of the plate blank is not uniform.
The hot rolling deformation is required to be controlled to be not less than 25% so as to eliminate the nonuniformity and defects of the internal structure of the casting blank; the hot rolling of the slab is required to be completed by controlling the finish rolling temperature to 800 ℃ or more, and too low finish rolling temperature causes too high deformation resistance of the slab, so that it is difficult to manufacture a hot rolled steel sheet having a desired thickness specification and having no surface and edge defects.
(2) Hot rolling post-annealing process
And annealing the hot rolled steel sheet. In the invention, the soaking temperature is 650-1100 ℃, and the soaking time is 0.5-10 h. The process aims to eliminate hot rolling deformation structure and realize microstructure regulation to obtain target microstructure. The annealing process conditions of the invention are closely related to the alloy components of the steel grade. When the soaking temperature is lower than 650 ℃, the hot rolling deformation structure can not be fully eliminated, a large amount of dislocation tangles existing in the alloy matrix can interact with martensite formed by stress/strain induction in the process of alternating load action, and then the reversible phase transformation between austenite and martensite is inhibited; when the soaking temperature is higher than 1100 ℃, austenite grains of an alloy matrix are too coarse, and the room-temperature low-cycle fatigue life of the alloy is also damaged. Therefore, the soaking temperature of annealing after hot rolling is controlled to be 650-1100 ℃. In the annealing process, the soaking time can be adjusted by properly changing the soaking temperature, and the production efficiency is influenced by overlong heat preservation time, so that the soaking time is controlled not to exceed 10 hours.
The second preparation method of the Fe-Mn-Si-Ni-C series elastic-plastic damping steel comprises the following steps:
1) smelting and casting according to the following component proportion to obtain a casting blank,
the mass percentage of the chemical components is as follows: 20.0% to 34.0% of Mn, 3.5% to 6.0% of Si, 0.1% to 5.0% of Ni, 0.005% to 0.15% of C, 0.02% to 0.02% of P, 0.03% to 0.03% of S, 0.02% to N and the balance of Fe and inevitable impurity elements, wherein the mass percentages of the Mn, the Ni and the C elements also need to satisfy the following relations: mn +1.6Ni +52C is more than or equal to 32 percent and Mn +2Ni is less than or equal to 37 percent;
2) hot rolling
Heating the casting blank at 1000-1250 ℃, wherein the heat preservation time is 0.5-3 h, the hot rolling casting blank is a hot rolled plate, the hot rolling deformation is more than or equal to 25%, and the final rolling temperature is more than or equal to 800 ℃;
3) acid pickling
4) Cold rolling
Cold rolling the hot rolled plate after acid washing, wherein the cold rolling deformation is less than or equal to 60 percent, and obtaining the cold rolled plate;
5) annealing after cold rolling
Heating the cold-rolled sheet to a soaking temperature of 720-1100 ℃ and soaking time of 0.5-10 h; and cooling the steel plate to room temperature after the annealing is finished.
The second preparation method of the Fe-Mn-Si-Ni-C series elasto-plastic damping steel has the following design reasons:
(1) hot rolling process
The heating temperature is 1000-1250 ℃, and when the heating temperature exceeds 1250 ℃, the over-burning of the cast plate blank can be caused, and the grain structure in the plate blank is coarse, so that the hot processing performance is reduced; when the heating temperature is lower than 1000 ℃, after the plate blank is descaled by high-pressure water and is initially rolled, the finish rolling temperature is too low, so that the deformation resistance of the plate blank is too high, and the hot-rolled steel plate which has no surface defects and has a specified thickness is difficult to manufacture.
The heat preservation time is 0.5-3 h during hot rolling, and the heat preservation time exceeds 3h, so that the grain structure in the plate blank is coarse; the heat preservation time is less than 0.5h, and the internal temperature of the plate blank is not uniform.
The hot rolling deformation is required to be controlled to be not less than 25% so as to eliminate the nonuniformity and defects of the internal structure of the casting blank; the hot rolling of the slab is required to be completed by controlling the finish rolling temperature to 800 ℃ or more, and too low finish rolling temperature causes too high deformation resistance of the slab, so that it is difficult to manufacture a hot rolled steel sheet having a desired thickness specification and having no surface and edge defects.
(2) Cold rolling process
And (3) performing cold rolling deformation on the plate blank subjected to hot rolling and pickling to a specified thickness, wherein the cold rolling deformation is not more than 60%. If the deformation exceeds 60%, the alloy has high deformation resistance, the manufacturing difficulty is increased, the possibility of edge crack of the steel plate is increased, and the production efficiency is reduced. In addition, cold rolling deformation forms complex deformation structures and crystal defects in the alloy matrix, such as dislocation tangles, interactions between dislocations and stress/strain-induced martensite, and interactions between stress/strain-induced polytropic martensite. After recrystallization annealing, due to the reasons of the tissue genetic relationship or no clear crystallographic orientation of the alloy and the like, the complex multi-variant martensite is easily formed in the alloy again in the cyclic loading process, so that the occurrence of reversible transformation between austenite and martensite is prevented, and the low cycle fatigue life of the alloy is reduced.
(3) Annealing process after cold rolling
The cold-rolled steel sheet is subjected to annealing heat treatment. In the invention, the soaking temperature is 720-1100 ℃, and the soaking time is 0.5-10 h. The purpose of the process is to eliminate the complex cold-rolled deformation structure and crystal defects and form a recrystallization structure. The annealing process conditions of the invention are closely related to the alloy components of the steel grade. When the soaking temperature is lower than 720 ℃, the cold-rolled deformation structure can not be fully eliminated, a large amount of dislocation tangles existing in the alloy matrix and martensite caused by cold-rolled deformation interact with martensite formed by stress/strain induction in the process of alternating load action, and the reversibility of austenite and martensite phase transformation is further inhibited; in addition, too low soaking temperature can make recrystallized austenite grains too fine, and the fine austenite grains can inhibit the occurrence of martensite phase transformation, thereby reducing the low cycle fatigue life of the alloy. When the soaking temperature is higher than 1100 ℃, the austenite structure of the alloy matrix is excessively coarsened, and the room-temperature low-cycle fatigue life of the alloy is also reduced. Therefore, the soaking temperature is controlled to be 720-1100 ℃. In the annealing process, the soaking time can be adjusted by properly changing the soaking temperature, and the production efficiency is influenced by overlong heat preservation time, so that the soaking time is controlled not to exceed 10 hours.
By adopting the component design, rolling process and annealing process, the prepared steel plate has an original matrix microstructure of austenite and martensite with volume fraction not more than 10%. The invention utilizes the reversible phase transformation between austenite and martensite of the microstructure of the steel plate matrix in the action process of the tensile-compression cycle load or the shearing cycle load to reduce the generation of crystal defects and delay the expansion of fatigue cracks, so that the material has good room-temperature low-cycle fatigue life.
In order to ensure the reversible transformation between austenite and martensite under the action of the microstructure and the cyclic load, the contents of Mn, Si, Ni and C are controlled within a specified range, and the contents of Mn, Ni and C in percentage by mass need to satisfy the following relations: mn +1.6Ni +52C is more than or equal to 32 percent and Mn +2Ni is less than or equal to 37 percent; in addition, it is also necessary to achieve this by tightly controlling the rolling and annealing processes. The mechanical properties of the finally obtained elastic-plastic damping steel plate are as follows: yield strength (or specified non-proportional elongation strength R)p0.2) Less than 360 MPa; under the condition of cyclic tensile-compression loading, when the strain amplitude, the strain ratio and the loading frequency are respectively 1%, -1.0 and 0.1-0.2 Hz, the stress amplitude is less than 530MPa and the room-temperature fatigue life of the steel plate is more than 2000 cycles.
In the above, the mass percentages of the Mn, Ni and C elements also need to satisfy the following relationship: mn +1.6Ni +52C is more than or equal to 32 percent and Mn +2Ni is less than or equal to 37 percent, the elements are calculated by mass percentage, and the coefficients in front of the elements are multiples of the contents.
The third aspect of the invention provides the application of the Fe-Mn-Si-Ni-C series elastic-plastic damping steel:
the Fe-Mn-Si-Ni-C series elastic-plastic damping steel is used for manufacturing steel dampers placed in buildings or structures so as to improve the seismic performance of the buildings and the structures.
The damping steel has the characteristics of lower yield strength, excellent low-cycle fatigue performance and the like, the excellent low-cycle fatigue performance of the damping steel is derived from reversible phase transformation between austenite and martensite (with a close-packed hexagonal crystal structure) of a microstructure in a material under the condition of cyclic stretching-compressing or cyclic shearing loading, and α' martensite (with a body-centered tetragonal crystal structure) is inhibitedp0.2) Less than 360 MPa; under the condition of cyclic loading, when the strain amplitude, the strain ratio and the loading frequency are respectively 1%, -1.0 and 0.1-0.2 Hz, the stress amplitude is less than 530MPa, and the room-temperature fatigue life of the steel plate is more than 2000 cycles. The steel plate is suitable for manufacturing steel shock-absorbing dampers.
Compared with the prior art, the invention has the following beneficial effects:
1. compared with the traditional elastic-plastic damping steel (such as mild steel and low yield point steel), the steel of the invention has obviously improved room temperature low cycle fatigue performance and can be used in the environment of frequent and high-intensity vibration; in addition, the steel grade of the invention also has relatively high strength, which is beneficial to realizing the light weight of the steel damper.
2. The invention realizes the reversible phase transformation between austenite and martensite of the microstructure of the ferro-manganese alloy steel matrix under the action of cyclic load mainly by controlling the contents of Mn, Si, Ni and C elements, thereby leading the material to have good room temperature low cycle fatigue life and energy dissipation and shock absorption characteristics. Compared with other damping alloys (such as manganese-copper alloy and nickel-titanium alloy), the elastoplasticity damping steel obviously has the advantage of low cost.
3. The elastic-plastic damping steel has excellent mechanical property and excellent welding property.
4. The composition design of the elastic-plastic damping steel does not take Al alloying as an important technical approach, so that the manufacturability of the steel grade is better.
5. The manufacturing process of the invention can be completed on the existing steel plate production line without major adjustment. Therefore, the invention has good popularization and application prospect.
Drawings
FIG. 1 is a plot of hysteresis curves of steel grades shown in example 4 of Table 1 loaded at different cycles of the tension-compression cycle (loading conditions: strain amplitude, strain ratio and loading frequency are 1%, -1.0 and 0.2Hz, respectively); low cycle fatigue life N of this steel gradef7819 weeks.
FIG. 2 shows the tensile stress amplitude and the compressive stress amplitude of the steel grades shown in example 4 of Table 1 at different times of the tensile-compressive cycle loading conditions (loading conditions: strain amplitude, strain ratio and loading frequency are 1%, -1.0 and 0.2Hz, respectively).
Detailed Description
The high-performance elastic-plastic damping steel comprises the following chemical components in percentage by mass: 20.0% to 34.0% of Mn, 3.5% to 6.0% of Si, 0.1% to 5.0% of Ni, 0.005% to 0.15% of C, 0.02% to 0.02% of P, 0.03% to 0.03% of S, 0.02% to N and the balance of Fe and inevitable impurity elements, wherein the mass percentages of the Mn, the Ni and the C elements also need to satisfy the following relations: mn +1.6Ni +52C is more than or equal to 32 percent and Mn +2Ni is less than or equal to 37 percent.
The first preparation method of the high-performance elastic-plastic damping steel comprises the following steps:
1) smelting and casting according to the following component proportion to obtain a casting blank
The mass percentage of the chemical components is as follows: 20.0% to 34.0% of Mn, 3.5% to 6.0% of Si, 0.1% to 5.0% of Ni, 0.005% to 0.15% of C, 0.02% to 0.02% of P, 0.03% to 0.03% of S, 0.02% to N and the balance of Fe and inevitable impurity elements, wherein the mass percentages of the Mn, the Ni and the C elements also need to satisfy the following relations: mn +1.6Ni +52C is more than or equal to 32 percent and Mn +2Ni is less than or equal to 37 percent;
2) hot rolling
Heating the casting blank at 1000-1250 ℃, wherein the heat preservation time is 0.5-3 h, the hot rolling casting blank is a hot rolled plate, the hot rolling deformation is more than or equal to 25%, and the final rolling temperature is more than or equal to 800 ℃;
3) post hot rolling annealing
Heating the hot rolled plate to the soaking temperature of 650-1100 ℃ and soaking time of 0.5-10 h; and cooling the steel plate to room temperature after the annealing is finished.
The second preparation method of the high-performance elastic-plastic damping steel comprises the following steps:
1) smelting and casting according to the following component proportion to obtain a casting blank
The mass percentage of the chemical components is as follows: 20.0% to 34.0% of Mn, 3.5% to 6.0% of Si, 0.1% to 5.0% of Ni, 0.005% to 0.15% of C, 0.02% to 0.02% of P, 0.03% to 0.03% of S, 0.02% to N and the balance of Fe and inevitable impurity elements, wherein the mass percentages of the Mn, the Ni and the C elements also need to satisfy the following relations: mn +1.6Ni +52C is more than or equal to 32 percent and Mn +2Ni is less than or equal to 37 percent;
2) hot rolling
Heating the casting blank at 1000-1250 ℃, wherein the heat preservation time is 0.5-3 h, the hot rolling casting blank is a hot rolled plate, the hot rolling deformation is more than or equal to 25%, and the final rolling temperature is more than or equal to 800 ℃;
3) acid pickling
4) Cold rolling
Cold rolling the hot rolled plate after acid washing, wherein the cold rolling reduction is less than or equal to 60 percent, and obtaining the cold rolled plate;
5) annealing after cold rolling
Heating the cold-rolled sheet to a soaking temperature of 720-1100 ℃ and soaking time of 0.5-10 h; and cooling the steel plate to room temperature after the annealing is finished.
The invention is described in detail below with reference to the figures and specific embodiments.
Table 1 shows the alloy compositions (Fe element content as the balance) of the steel grades of the examples of the invention and the comparative examples; table 2 shows the manufacturing process of steel grades according to examples of the invention and comparative examples; table 3 shows the mechanical properties and room temperature low cycle fatigue properties of the steel sheets of the examples of the present invention and the comparative examples.
The content ratios of the components in examples 1 to 14 and comparative examples 1 to 3 were designed as shown in Table 1.
TABLE 1 (unit: wt%)
Steel materials having the compositions shown in table 1 were made into slabs after smelting and casting. Heating the plate blank at the heating temperature of 1200 ℃, carrying out hot rolling on the plate blank after the heat preservation time is 1.5h, and finishing the hot rolling and finish rolling at the finishing temperature of 860 ℃, wherein the accumulated deformation of the hot rolling exceeds 25%.
And (3) cooling the hot-rolled steel plate to room temperature after the hot-rolled steel plate is subjected to a hot rolling and annealing process or a cold rolling and annealing process (the specific process conditions are shown in table 2), so as to obtain the target damping steel plate.
TABLE 2
The mechanical properties and room temperature low cycle fatigue properties of the steel sheets of examples 1 to 14 of the present invention and comparative examples 1 to 3 are shown in Table 3.
TABLE 3
As can be seen from Table 3, the present invention can obtain high performance elastoplastic damping steel plate with yield strength (or specified non-proportional elongation strength R) by reasonable composition and process designp0.2) Less than 360 MPa; under the condition of cyclic tensile-compression loading, when the strain amplitude, the strain ratio and the loading frequency are respectively 1%, -1.0 and 0.1-0.2 Hz, the stress amplitude is less than 530MPa and the room-temperature fatigue life of the steel plate is more than 2000 cycles. As shown in FIG. 1, the steel grade of the present invention has stable hysteresis characteristics during the loading of the tension-compression cycle and a full hysteresis curve。
The embodiments described above are described to facilitate an understanding and use of the invention by those skilled in the art. It will be readily apparent to those skilled in the art that various modifications to these embodiments may be made, and the generic principles described herein may be applied to other embodiments without the use of the inventive faculty. Therefore, the present invention is not limited to the above embodiments, and those skilled in the art should make improvements and modifications within the scope of the present invention based on the disclosure of the present invention.
Claims (7)
1. A rolled plate made of Fe-Mn-Si-Ni-C series elastoplastic damping steel is characterized by comprising the following chemical components in percentage by mass: 20.0% to 34.0% of Mn, 3.5% to 6.0% of Si, 0.1% to 5.0% of Ni, 0.005% to 0.15% of C, 0.02% to 0.02% of P, 0.03% to 0.03% of S, 0.02% to N and the balance of Fe and inevitable impurity elements, wherein the mass percentages of the Mn, the Ni and the C elements also need to satisfy the following relations: mn +1.6Ni +52C is more than or equal to 32 percent and Mn +2Ni is less than or equal to 37 percent;
the microstructure of the Fe-Mn-Si-Ni-C series elastic-plastic damping steel is austenite and martensite with the volume fraction not more than 10%;
the yield strength of the Fe-Mn-Si-Ni-C series elastic-plastic damping steel is less than 360 MPa;
under the cyclic tension-compression loading condition, when the strain amplitude, the strain ratio and the loading frequency are respectively 1%, -1.0 and 0.1-0.2 Hz, the stress amplitude is less than 530MPa, and the room-temperature fatigue life of the steel plate is more than 2000 weeks.
2. The rolled plate material of Fe-Mn-Si-Ni-C series elasto-plastic damping steel as claimed in claim 1, wherein the chemical composition of the Fe-Mn-Si-Ni-C series elasto-plastic damping steel comprises Si by mass percent: 4.0% -5.0%.
3. The rolled plate of the Fe-Mn-Si-Ni-C series elasto-plastic damping steel as claimed in claim 1, wherein the chemical components in percentage by mass are as follows: mn is more than or equal to 20.0 percent and less than or equal to 25.0 percent, Si is more than or equal to 3.5 percent and less than or equal to 4.2 percent, Ni is more than or equal to 0.1 percent and less than or equal to 3.2 percent, C is more than or equal to 0.005 percent and less than or equal to 0.102 percent, P is less than or equal to 0.02 percent, S is less than or equal to 0.03 percent, N is less than or equal to 0.02 percent, and the balance is Fe and inevitable impurity elements, wherein the mass percentage content of the Mn, the Ni: mn +1.6Ni +52C is more than or equal to 32 percent and Mn +2Ni is less than or equal to 37 percent.
4. The rolled plate material of Fe-Mn-Si-Ni-C elasto-plastic damping steel as claimed in claim 3, wherein the chemical composition of the Fe-Mn-Si-Ni-C elasto-plastic damping steel comprises Mn, Si, Ni and C in percentage by mass: mn is more than or equal to 23.2 percent and less than or equal to 25.0 percent, Si is more than or equal to 3.92 percent and less than or equal to 4.2 percent, Ni is more than or equal to 2.46 percent and less than or equal to 3.2 percent, and C is more than or equal to 0.060 percent and less than or equal to 0.102 percent.
5. A method for producing a rolled plate of an elasto-plastic damping steel of the Fe-Mn-Si-Ni-C series as claimed in any one of claims 1 to 4, characterized by comprising the steps of:
1) smelting and casting according to the following component proportion to obtain a casting blank,
the mass percentage of the chemical components is as follows: 20.0% to 34.0% of Mn, 3.5% to 6.0% of Si, 0.1% to 5.0% of Ni, 0.005% to 0.15% of C, 0.02% to 0.02% of P, 0.03% to 0.03% of S, 0.02% to N and the balance of Fe and inevitable impurity elements, wherein the mass percentages of the Mn, the Ni and the C elements also need to satisfy the following relations: mn +1.6Ni +52C is more than or equal to 32 percent and Mn +2Ni is less than or equal to 37 percent;
2) hot rolling
Heating the casting blank at 1000-1250 ℃, wherein the heat preservation time is 0.5-3 h, the hot rolling casting blank is a hot rolled plate, the hot rolling deformation is more than or equal to 25%, and the final rolling temperature is more than or equal to 800 ℃;
3) post hot rolling annealing
Heating the hot rolled plate to the soaking temperature of 650-1100 ℃ and soaking time of 0.5-10 h; and cooling the steel plate to room temperature after the annealing is finished.
6. A method for producing a rolled plate of an elasto-plastic damping steel of the Fe-Mn-Si-Ni-C series as claimed in any one of claims 1 to 4, characterized by comprising the steps of:
1) smelting and casting according to the following component proportion to obtain a casting blank,
the mass percentage of the chemical components is as follows: 20.0% to 34.0% of Mn, 3.5% to 6.0% of Si, 0.1% to 5.0% of Ni, 0.005% to 0.15% of C, 0.02% to 0.02% of P, 0.03% to 0.03% of S, 0.02% to N and the balance of Fe and inevitable impurity elements, wherein the mass percentages of the Mn, the Ni and the C elements also need to satisfy the following relations: mn +1.6Ni +52C is more than or equal to 32 percent and Mn +2Ni is less than or equal to 37 percent;
2) hot rolling
Heating the casting blank at 1000-1250 ℃, wherein the heat preservation time is 0.5-3 h, the hot rolling casting blank is a hot rolled plate, the hot rolling deformation is more than or equal to 25%, and the final rolling temperature is more than or equal to 800 ℃;
3) acid pickling
4) Cold rolling
Cold rolling the hot rolled plate after acid washing, wherein the cold rolling deformation is less than or equal to 60 percent, and obtaining the cold rolled plate;
5) annealing after cold rolling
Heating the cold-rolled sheet to a soaking temperature of 720-1100 ℃ and soaking time of 0.5-10 h; and cooling the steel plate to room temperature after the annealing is finished.
7. Use of a rolled sheet of Fe-Mn-Si-Ni-C elasto-plastic damping steel according to any one of claims 1 to 4 for the manufacture of a steel damper for placement in a building or structure.
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