CN114686655A - Rapid spheroidizing annealing method for GCr15 steel - Google Patents
Rapid spheroidizing annealing method for GCr15 steel Download PDFInfo
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- 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
- C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
- C21D1/26—Methods of annealing
- C21D1/32—Soft annealing, e.g. spheroidising
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- 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
- C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
- C21D1/34—Methods of heating
- C21D1/42—Induction heating
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- 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
- C21D6/00—Heat treatment of ferrous alloys
- C21D6/002—Heat treatment of ferrous alloys containing Cr
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- 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
- C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
- C21D9/52—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for wires; for strips ; for rods of unlimited length
- C21D9/525—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for wires; for strips ; for rods of unlimited length for wire, for rods
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
- Y02P10/25—Process efficiency
Abstract
The invention relates to a rapid spheroidizing annealing method of GCr15 steel. According to the method, the annealed GCr15 steel is directly placed in a Formastor high-frequency induction line device, the temperature rise and the temperature fall are rapidly completed within 10s, and the austenitizing and spheroidizing processes are directly completed in a high-frequency coil, so that the time is greatly shortened; meanwhile, the invention effectively shortens the temperature fluctuation range, reduces the process of normalizing and then spheroidizing annealing in the traditional process, obtains the medium-temperature bainite structure by isothermal quenching and then spheroidizing annealing, avoids a large amount of temperature rise and drop processes and greatly reduces the energy consumption. The invention has simple flow, high efficiency and energy saving, adjusts the heat preservation temperature, the heat preservation time and the cooling rate of the spheroidizing annealing by high-frequency rapid heating and cooling, obviously improves the spheroidizing annealing efficiency of the GCr15 steel and improves the spheroidizing annealing effect.
Description
Technical Field
The invention relates to the field of steel, in particular to an online rapid spheroidizing annealing method for a GCr15 bearing steel wire.
Background
Bearing steel is an important component of mechanical equipment due to its good toughness and high fatigue resistance and wear resistance. With the continuous progress of technical equipment such as smelting, rolling, heat treatment and the like, the requirements on bearing steel are continuously improved, and a spheroidizing annealing mode which is one of key links for controlling the quality of carbide is particularly important.
The GCr15 steel is a typical bearing steel, and its original structure is generally lamellar pearlite, which has high hardness, high brittleness, easy cracking, and difficult cutting, and thus, spheroidizing is often required. The spheroidized structure is spherical pearlite after spheroidizing, the strength and the hardness are slightly low, but the plasticity, the machinability and the cold working formability are low, the quenching deformation and the cracking tendency are low, and the structure preparation is made for subsequent heat treatment. However, the cooling speed of the common spheroidizing annealing is slow, the production period is long, and therefore, an important problem which must be considered is how to shorten the annealing time and reduce the energy consumption in the production practice so as to achieve the purpose of improving the production efficiency. Therefore, how to combine the faster production time, the lower energy consumption and the better performance of the steel becomes a technical problem to be solved urgently in the field.
At present, for spheroidizing annealing technologies in the field of steel and iron, researches on spheroidizing annealing technologies of GCr15 steel, H13 steel, gear steel, cutter steel and other steel types are more, for example, a patent No. CN102382962B discloses a rapid spheroidizing annealing technology for GCr15 bearing steel tubes, the process is relatively complex, the temperature rise and fall time is longer, and the process duration and energy consumption are greatly increased.
The CN201710411463.0 patent of GCr15 bearing steel on-line rapid spheroidizing annealing method after hot rolling adopts an optimized spheroidizing process, controls the precipitation of the pre-eutectoid carbide in the rolling process in a deformation induction mode, shortens the time required by spheroidizing annealing, and improves the energy efficiency; CN201810318301.7 patent "A Rapid spheroidizing annealing Process method of GCr15 bearing Steel" this method controls the size of the eutectoid carbide effectively, offer more nucleation positions for the precipitation of cementite in the eutectoid transformation process, thus shorten the time needed for spheroidizing annealing effectively, raise the energy efficiency; the invention of the patent GCr15 quick spheroidizing annealing process of the bearing steel pipe with the patent number of CN201110354494.X effectively shortens the retention time of a reticular carbide precipitation interval, achieves the aim of inhibiting the precipitation of the reticular carbide, can obtain a good spheroidizing structure in a short time, and greatly shortens the spheroidizing time. The three rapid spheroidizing annealing processes only stay on the improvement of the spheroidizing annealing process of the pearlite after rolling, but the spheroidizing annealing process of the pearlite is long in time consumption, and the bearing steel before spheroidizing annealing generally needs to be normalized to room temperature, needs to be heated and cooled in a large amount, wastes a lot of energy, and does not fundamentally solve the energy consumption problem of spheroidizing annealing.
Disclosure of Invention
The invention aims to provide a rapid spheroidizing annealing method for GCr15 steel aiming at the problems of the prior GCr15 steel in the spheroidizing annealing technology. According to the method, the annealed GCr15 steel is directly placed in a Formastor high-frequency induction line device, the temperature rise and the temperature fall are rapidly completed within 10s, and the austenitizing and spheroidizing processes are directly completed in a high-frequency coil, so that the time is greatly shortened; meanwhile, the invention effectively shortens the temperature fluctuation range, reduces the process that the traditional process firstly normalizes to eliminate secondary carbides and then performs spheroidizing annealing, adopts quenching to obtain a medium-temperature bainite structure and then performs spheroidizing annealing, avoids a large amount of heating and cooling processes, and greatly reduces the energy consumption, which is also the unique point of the invention. The invention has simple flow, high efficiency and energy saving, adjusts the heat preservation temperature, the heat preservation time and the cooling rate of the spheroidizing annealing by high-frequency rapid heating and cooling, obviously improves the spheroidizing annealing efficiency of the GCr15 steel and improves the spheroidizing annealing effect.
The technical scheme of the invention is as follows:
a rapid spheroidizing annealing method of GCr15 steel comprises the following steps: the wire rod of GCr15 steel was placed in a high-frequency induction device and the following operations were performed:
(1) heating the wire to 880-980 ℃ in 5-10 s, and preserving the heat for 15-30 min at the temperature until the sample is completely austenitized;
(2) rapidly cooling the wire to 400 +/-10 ℃ within 5-10 s, and preserving heat for 425-445 s;
(3) rapidly heating the wire to 678 +/-10 ℃ for 5-10 s, and preserving the heat for 90-120 s;
(4) rapidly reducing the temperature of 578 +/-10 ℃ in 5-10 s, and then preserving the heat for 50-75 s;
(5) and rapidly cooling the wire rod subjected to heat preservation again to room temperature for 5-10 s to complete spheroidizing annealing.
The GCr15 steel comprises the following components in percentage by weight: 0.95-1.10%, Si: 0.15-0.35%, Mn: less than or equal to 0.5 percent, Cr: 1.30-1.60% and the balance Fe.
The high-frequency induction device is a Formastor high-frequency induction device, and the diameter of the GCr15 steel wire rod is 2.5-3.5 mm.
The pearlite transformation to austenite start temperature is specifically 628 ℃.
The austenite to bainite transformation start temperature is 400 ℃.
The invention has the substantive characteristics that:
in the prior art, the conventional spheroidizing annealing process is to perform normalizing (cooling to room temperature) first and then put into an annealing furnace to perform a slow spheroidizing annealing process. The core innovation point of the method is that the two processes are combined, a sample is directly placed in a high-frequency induction furnace to be austenitized, normalizing (namely cooling to room temperature) is not carried out, medium-temperature bainite transformation (cooling to about 400 ℃) is directly carried out, then the temperature is rapidly reduced to finish heat preservation of the two temperatures, the performance can also reach the relevant requirements, and the energy consumption is greatly reduced. The rapid temperature rise and fall of the process is realized by a Formastor high-frequency induction device, and the conventional annealing furnace cannot achieve the rapid temperature rise and fall.
The mechanism is that the conventional spheroidizing annealing process: the secondary carbides are broken by normalizing and then partially fused into austenite by long-term annealing and holding, leaving a considerable amount of undissolved carbides, which are precipitated during subsequent cooling, centered on these residual carbides.
And (3) a rapid annealing process: a certain amount of undissolved carbide is obtained directly through bainite transformation with short energy consumption (not reduced to room temperature and less energy is needed), then a small amount of secondary carbide is crushed through the first quick temperature isothermy, and the second quick heat preservation takes the undissolved carbide as a core to precipitate the carbide, because the same performance can be realized.
The other innovation point of the invention is that the material is selected as wire, and the time of the heat treatment process is controlled by the moving speed of the wire in the induction coil; and secondly, the use of a high-frequency induction coil and rapid cooling can combine two procedures of the conventional process, thereby greatly reducing the use and time of equipment.
The invention has the beneficial effects that:
the GCr15 steel rapid spheroidizing annealing process implemented by the technical scheme has the advantages that the carbide is spheroidized on line through high-frequency induction rapid heating and two-path rapid cooling channel of steam/water, the time of the whole process flow is only about 0.5h, the spheroidizing annealing period is greatly shortened, the energy consumption is greatly reduced, the carbide is uniformly distributed, the carbide aggregation is avoided, the carbide particles are fine, the process is simple, the principle is clear, and the industrial production is convenient.
The invention overcomes the defects that furnace body equipment needs more electric energy and damages the equipment after repeated high-low temperature circulation in the prior art, skillfully utilizes precursor treatment (the difference is mentioned), saves the electric energy, shortens the heat treatment time and achieves the same effect; not only is the time required shorter (process comparison can be seen), but also the electric energy required is less, and one ton of product can save about 100kWh of electricity.
Drawings
FIG. 1 is a schematic diagram of a specific process described in the present invention.
FIG. 2 is a schematic diagram of an apparatus for applying the process of the present invention (in the figure: 1. quartz tube, 2. gas tube, 3. cooling water tube, 4. sample, 5. thermocouple, 6. high frequency induction coil).
FIG. 3 shows metallographic structures of samples before being processed by all the examples.
FIG. 4 metallographic structure of the sample after the treatment in example 4.
The specific implementation mode is as follows:
the present invention will be described in more detail below with reference to the accompanying drawings by way of specific examples. An on-line rapid spheroidizing annealing process of GCr15 carbon tool steel is shown in figure 1. FIG. 2 is a schematic view of an application apparatus (high-frequency induction device) of the process of the present invention. The sample 4 is placed in a quartz tube 1, the quartz tube 1 sequentially surrounds an air tube 2, a cooling water tube 3 and a high-frequency induction coil 6, and the temperature of the sample is collected by a thermocouple 5. When the sample is heated, the high-frequency induction coil 6 is used for heating to achieve the purpose of rapidly heating the sample, and the gas pipe 2 is used for blowing the protective gas nitrogen to achieve the purpose of rapidly cooling the sample. FIG. 3 is a metallographic structure of a sample before being processed by the process of the present invention. The original microstructure of GCr15 before rapid spheroidizing was lamellar pearlite.
In the embodiment of the invention, the spheroidizing annealing high-frequency induction device is a Formaster-II type full-automatic phase change dilatometer of Fuji electric wave engineering Co., Ltd, hereinafter referred to as a Formasor high-frequency induction device. The device can realize the material rapid heating up, also enables material rapid cooling.
The equipment used for observing the metallographic microstructure in the embodiment of the invention is a Japanese Olympus metallographic microscope.
The national standard adopted for measuring the spheroidization grade in the embodiment of the invention is a rating method in GB/T18254-2016 high-carbon chromium bearing steel.
The present invention will be described in more detail with reference to the accompanying drawings. Through the GCr15 rapid spheroidizing annealing process shown in fig. 4, the microstructure after heat treatment is that fine and uniform spherical carbides are dispersed and distributed on a ferrite matrix.
The rapid spheroidizing annealing process of GCr15 bearing steel is shown in figure 1, and specifically comprises rapid heating, heat preservation, rapid cooling over Ac1, heat preservation and Ac1The following steps are carried out for heat preservation and quick cooling to room temperature:
1. a rapid heating process and a heat preservation process. The most basic problem of spheroidizing annealing is how to solve the formation of granular carbide cores, wherein granular carbides in the structure are formed by the growth of residual carbide particles during heating austenitization, and the more the residual carbide particles are, the easier the fully spheroidized structure is obtained, so that specific requirements on heating austenitization are required during spheroidizing. In austenitizing, the retained carbide particles are required to be as much as possible, austenite with as large as possible non-uniform carbon concentration is obtained, the non-uniformity of austenite components is beneficial to the nucleation and growth process of pearlite transformation, and undissolved carbide particles can become the non-uniform nucleation center of pearlite transformation, so that the abnormal decomposition rate of the supercooled austenite is 6-7 times faster than that of uniform austenite. Rapid temperature increase to the appropriate temperature and a short hold time are therefore required for the austenitizing stage. The invention adopts the steps of rapidly heating up to 980 ℃ in 10s and preserving the heat for 20 min.
2. And (5) rapidly cooling to a bainite transformation region. The net-shaped carbide needs to be eliminated before the hypereutectoid steel is spheroidized, and the quenching or normalizing process is generally adopted to eliminate the net-shaped carbide distributed in a chain shape along a crystal boundary. The invention only reduces the bainite area to the medium temperature, and achieves the effect of uniform distribution of carbide. The invention preserves heat at the bainite initial transformation temperature (400 ℃) for 435 s.
3. Rapid cooling Ac1And (5) preserving the heat. The process of rapid cooling increases the heterogeneity of austenite components and simultaneously reserves more undissolved carbide particles, proper heat preservation can promote the heterogeneity of crystal defects and structures to be obviously increased, and the residual carbide particles are more dispersed and fine. The invention is insulated for 102s at a temperature above Ac1 (678 ℃).
4. Rapid cooling Ac1The temperature was maintained as follows. In the temperature range, carbide structures can be separated out at positions with high linear defect density, dispersed granular carbides are formed in partial areas, finally, spheroidized structures are formed, and the formed carbide particles are small in size, round and uniform in appearance and dispersed in distribution. The invention is in Ac1The temperature was maintained for 60 seconds below (578 ℃).
5. And rapidly cooling to room temperature. The key of the GCr15 bearing steel rapid spheroidizing annealing process provided by the invention is to select a proper heat treatment process, heating temperature and heat preservation time, the process can greatly shorten the spheroidizing annealing period, save energy consumption and obtain a structure of fine, small, uniform and round carbide particles which are dispersedly distributed on a ferrite matrix, and the hardness is 28 HRC. The invention can ensure that the processed workpiece has good shaping processability and cutting performance, thereby improving the quality and the service performance of the product.
Example 1
(1) The GCr15 steel is selected as a wire rod with the diameter of 3mm, and comprises the following components in percentage by weight: 0.95-1.10%, Si: 0.15-0.35%, Mn: less than or equal to 0.5 percent, Cr: 1.30-1.60% and the balance Fe.
(2) Rapidly heating to 680 ℃ for 10s, and preserving the temperature for 20min until the sample is completely austenitized;
(3) rapidly cooling to 400 ℃ for 5s, and preserving heat for 435 s;
(4) rapidly heating to 678 ℃ for 5s, and preserving the temperature for 102 s;
(5) rapidly cooling (5s) to 578 ℃, and keeping the temperature for 60 s;
(6) and cooling to room temperature for 10 seconds to finish spheroidizing annealing.
Through the comprehensive control, part of the obtained carbide after spheroidizing annealing is spherical particles, part of the carbide is flaky pearlite, the distribution is not uniform, a large number of netlike cementite regions appear, and the grade is 5.
Example 2
(1) The GCr15 steel is selected as a wire rod with the diameter of 3mm, and comprises the following components in percentage by weight: 0.95-1.10%, Si: 0.15-0.35%, Mn: less than or equal to 0.5 percent, Cr: 1.30-1.60% and the balance Fe.
(2) Rapidly heating to 980 ℃ for 10s, and preserving the heat for 20min at the temperature until the sample is completely austenitized;
(3) rapidly cooling (5s) to room temperature;
(4) after the sample is cooled to room temperature, rapidly raising the temperature to 678 ℃ for 5s, and preserving the temperature for 102 s;
(5) rapidly cooling (5s) to 578 ℃, and keeping the temperature for 60 s;
(6) and cooling to room temperature for 10 seconds to finish spheroidizing annealing.
Through the comprehensive control, the obtained carbide after spheroidizing annealing is uniformly distributed in a spherical particle shape, no large cementite area appears, and the grade is 3. But the power consumption and time are increased invisibly.
Example 3
(1) The GCr15 steel is selected as a wire rod with the diameter of 3mm, and comprises the following components in percentage by weight: 0.95-1.10%, Si: 0.15-0.35%, Mn: less than or equal to 0.5 percent, Cr: 1.30-1.60% and the balance Fe.
(2) Rapidly heating to 980 ℃ for 10s, and preserving the heat for 20min at the temperature until the sample is completely austenitized;
(3) rapidly cooling to 400 ℃ for 5s, and preserving heat for 435 s;
(4) rapidly heating to 678 ℃ for 5s, and keeping the temperature for 300 s;
(5) rapidly cooling (5s) to 578 ℃, and keeping the temperature for 60 s;
(6) and cooling to room temperature for 10 seconds to finish spheroidizing annealing.
Through the comprehensive control, the obtained carbide after spheroidizing annealing is uniformly distributed in a spherical particle shape, no large cementite area appears, and the grade is 4. The second heat preservation time is too long.
Example 4
(1) The GCr15 steel is selected as a wire rod with the diameter of 3mm, and comprises the following components in percentage by weight: 0.95-1.10%, Si: 0.15-0.35%, Mn: less than or equal to 0.5 percent, Cr: 1.30-1.60% and the balance Fe.
(2) Rapidly heating to 980 ℃ for 10s, and preserving the heat for 20min at the temperature until the sample is completely austenitized;
(3) rapidly cooling to 400 ℃ for 5s, and preserving heat for 435 s;
(4) rapidly heating to 678 ℃ for 5s, and preserving the temperature for 102 s;
(5) rapidly cooling (5s) to 578 ℃, and keeping the temperature for 60 s;
(6) and cooling to room temperature for 10 seconds to finish spheroidizing annealing.
Through the above comprehensive control, the metallographic structure photograph of the sample obtained in this example is shown in fig. 4, and it can be seen from the photograph that the carbide obtained after spheroidizing annealing is uniformly distributed in the form of spherical particles, and no large cementite region appears, and the grade is 2. And the process time is shortest.
The rapid temperature rise to the complete austenite region is the key to ensure the later complete bainite or martensite transformation, if complete austenitization does not occur easily, the network cementite can not be eliminated in the later spheroidizing annealing, and can be brought to the later products, and the network cementite is the main reason of material cracking in the later use of the material (example 1). The patent skillfully utilizes pearlite to form pioneer carbide (both obtained in example 3 and example 4), and provides a prerequisite for later-stage spherical pearlite formation. Examples 3 and 4 austenitize the sample, do not carry on normalizing (i.e. do not need to cool to the room temperature), carry on the medium temperature bainite transformation directly (cool to about 400 ℃), avoid the sample heats repeatedly and causes the apparatus (example 2), and reduced the energy consumption. While proper incubation in the bainite region increases time (example 4), long waiting times and energy losses where the samples tend to equilibrate completely to room temperature are avoided (example 2). Example 3 is that the bainite complete transformation is completed and the carbide fracture is completed, and if the transformation time is additionally increased, the energy consumption is additionally increased.
The method adopts rapid induction heating and short-time heating/heat preservation, rapidly cools to the bainite region of the medium-temperature transformation region, rapidly breaks and dissolves carbide in lamellar spherical pearlite in the original annealing state, precipitates fine spherical carbide nucleation cores, and preserves heat for short time for two subsequent temperature sections to complete the spheroidization process. The short-time rapid induction heating treatment shortens the overall spheroidizing annealing time of GCr15 steel, improves the spheroidizing rate, greatly reduces the energy consumption, and has smaller and more uniform carbide size and distribution than the conventional spheroidizing annealing heat treatment.
The parameters of the GCr15 spheroidizing annealing heat treatment process and the comparative spheroidizing annealing heat treatment process are shown in Table 1.
TABLE 1 comparison of the parameters of the spheroidizing annealing heat treatment process of the present invention with the existing conventional spheroidizing annealing heat treatment process
From the above examples, we can see that the GCr15 steel can only be a bar material in order to control the temperature rise and fall speed; the diameter of the bar cannot be too large; the wire rod with the diameter of 3mm is only used, the core tissue can be easily achieved through short-time induction heating, the time is saved, the process is reduced, and the method is also an ingenious point of the method.
The Ac1 line in FIG. 1 is also called eutectoid line, and means that when iron-carbon alloy with carbon content of 0.77-2.11% is cooled to the line, eutectoid transformation, namely A, occurs at a constant temperature of 727 DEG0.77％→F0.0218％+Fe3C. Ac3 is the end temperature at which ferrite transforms into austenite upon heating. Because of the different carbon content and the change of alloy elements, the AC1 and AC3 change, the heat treatment temperature is generally between AC1 and AC3, so the heat treatment temperature changes, and the process needs to be researched again.
The above description is only for the preferred embodiment of the present invention, and the protection scope of the present invention is not limited thereto, so that any equivalent replacement or change made according to the scope of the present invention is within the protection scope of the present invention.
The invention is not the best known technology.
Claims (4)
1. A GCr15 steel rapid spheroidizing annealing method is characterized by comprising the following steps: the wire rod of GCr15 steel was placed in a high-frequency induction device and the following operations were performed:
(1) heating the bar to 880-980 ℃ in 5-10 s, and preserving the heat for 15-30 min at the temperature until the sample is completely austenitized;
(2) rapidly cooling the wire to 400 +/-10 ℃ within 5-10 s, and preserving heat for 425-445 s;
(3) rapidly heating the wire to 678 +/-10 ℃ for 5-10 s, and preserving the heat for 90-120 s;
(4) rapidly reducing the temperature of 578 +/-10 ℃ in 5-10 s, and then preserving the heat for 50-75 s;
(5) and rapidly cooling the wire rod subjected to heat preservation again to room temperature for 5-10 s to complete spheroidizing annealing.
2. The GCr15 steel rapid spheroidizing annealing method according to claim 1, wherein the GCr15 steel comprises the following components in percentage by weight: 0.95-1.10%, Si: 0.15-0.35%, Mn: less than or equal to 0.5 percent, Cr: 1.30-1.60% and the balance Fe.
3. The GCr15 steel rapid spheroidizing annealing method according to claim 1, wherein the high frequency induction device is a Formastor high frequency induction device.
4. The GCr15 steel rapid spheroidizing annealing method according to claim 1, wherein the diameter of the GCr15 steel wire rod is 2.5-3.5 mm.
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