CN118571383A - Method for rapidly predicting crack-arrest toughness of crack-arrest steel based on dynamic tear test - Google Patents
Method for rapidly predicting crack-arrest toughness of crack-arrest steel based on dynamic tear test Download PDFInfo
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Abstract
The invention provides a method for rapidly predicting crack-arrest toughness of crack-arrest steel based on a dynamic tearing test, which comprises the following steps: s1, obtaining crack-arrest toughness K ca of crack-arrest steels with different thicknesses and different strength grades, which are measured under a double tensile test; s2, carrying out a series of temperature dynamic tearing oscillometric impact tests on the crack-arrest steels with different thicknesses and different strength grades to obtain the ductile-brittle transition temperature ETT 50 of the impact test at each temperature; s3, establishing a correlation model of crack arrest toughness K ca and impact test ductile-brittle transition temperature ETT 50; s4, when the crack-stopping toughness of the crack-stopping steel is predicted subsequently, obtaining the ductile-brittle transition temperature ETT 50 of the impact test through a series of temperature dynamic tearing oscillometric impact tests, and substituting the ductile-brittle transition temperature ETT 50 into a correlation model to obtain the crack-stopping toughness. According to the method for rapidly predicting the crack-stopping toughness of the crack-stopping steel based on the dynamic tearing test, disclosed by the invention, the dynamic tearing test is used for replacing a dual tensile test to predict the crack-stopping toughness of the crack-stopping steel, so that the period is short and the cost is low.
Description
Technical Field
The invention relates to the technical field of hull structural steel fracture and crack arrest, in particular to a method for rapidly predicting crack arrest toughness of crack arrest steel based on a dynamic tearing test.
Background
With the development demand of low-carbon economy, the development of container ships tends to be larger, and oversized container ships above 24000TEU are gradually brought into the design, construction and operation stages and become one of the dominant ship types in the next years. Compared with a small-sized and medium-sized container ship, the stress state of the hull structure of the large-sized container ship is obviously deteriorated, the large size and the large opening characteristic of the hull can enable the hull structure to be subjected to combined action of various loads, the requirements of total longitudinal bending strength and buckling strength and large opening (torsion) strength are met, and the hatch coaming plate, the web plate, the upper deck sideboard, the topboard and certain local areas (hatch corners) in the hull structure are at high stress level. In order to ensure the safety and reliability of the hull structure and prevent brittle fracture damage, high-strength and large-thickness crack-arrest steel can be generally used in a high-stress area of the hull. When the hull is subjected to fatigue fracture, the crack is expanded to the crack-stopping steel, and then the expansion is stopped, so that a catastrophic fracture accident is avoided. The large-scale application of the crack-arrest steel provides important guarantee for improving the safe and green operation of the container ship.
The crack-stopping toughness is a core index for evaluating the performance quality of the crack-stopping steel, and the crack-stopping steel needs to be subjected to multiple rounds of composition and process optimization during research, development, trial production and real ship application, and each round of iteration needs to be tested for the crack-stopping performance. The patent of application number CN202310298502.6 in the prior art discloses a construction method of a prediction model for ductile-brittle transition high-order energy of high-strength structural steel, and does not relate to any description of crack-arrest toughness. Usually, crack-arrest toughness at-10 ℃ is adopted(Hereinafter abbreviated as K ca) as a design basis. According to international classification society specification UR W31 and Chinese classification society's application guide for high-strength thick plates for ships' and other industry specifications, ladder-temperature type dual tensile test is generally adopted to measure crack-arrest toughness K ca, and the dual tensile test sample is 500mm multiplied by t, wherein t is the plate thickness, and the test principle and the test sample are shown in figures 1 and 2. The temperature gradient field is achieved by applying a heat source and a cold source to the crack propagation region of the sample. In order to obtain crack arrest toughness at-10deg.C, 4 groups of tests are generally required, and interpolation is used to obtainAs shown in fig. 4. The double tensile test is required to be carried out on a 5000-ton large tensile tester, and a large amount of cooling liquid is required to be consumed when a temperature field is established, so that the test period is long and the cost is high.
In summary, in the prior art, the fracture toughness K ca is measured by adopting a ladder temperature type double tensile test, on one hand, the double tensile test at least needs 4 pairs of test boards with the thickness of 500mm multiplied by the original board thickness, and the test boards need large-scale rolling, so that the material and processing cost are high; on the other hand, the double tensile test is required to be carried out on a 5000-ton large-scale tensile testing machine, a large amount of welding materials are required to be consumed for testing tool assembly, a large amount of cooling liquid is required to be consumed when a temperature field is established, the testing period is long, and the cost is high.
In view of this, the present invention has been made.
Disclosure of Invention
The invention aims to provide a method for rapidly predicting the crack-stopping toughness of a crack-stopping steel based on a dynamic tearing test, which aims to solve the problems that in the prior art, a ladder-temperature type double tensile test is adopted to measure the crack-stopping toughness K ca, on one hand, the double tensile test at least needs 4 pairs of test boards with the thickness of 500mm multiplied by the original board, large-scale rolling is needed, and the material and processing cost are high; on the other hand, the double tensile test is required to be carried out on a 5000-ton large-scale tensile testing machine, a large amount of welding materials are required to be consumed for testing tool assembly, a large amount of cooling liquid is required to be consumed when a temperature field is established, and the problems of long testing period and high cost are solved.
In order to achieve the above purpose, the technical scheme of the invention is realized as follows:
A method for rapidly predicting crack-arrest toughness of crack-arrest steel based on a dynamic tear test, the method for rapidly predicting crack-arrest toughness of crack-arrest steel based on a dynamic tear test comprises the following steps:
S1, obtaining crack-arrest toughness K ca of crack-arrest steels with different thicknesses and different strength grades, which are measured under a double tensile test;
S2, carrying out a series of temperature dynamic tearing oscillometric impact tests on the crack-arrest steels with different thicknesses and different strength grades in the step S1 to obtain impact test ductile-brittle transition temperatures ETT 50 at each temperature;
S3, establishing a correlation model of crack arrest toughness K ca and impact test ductile-brittle transition temperature ETT 50;
s4, when the crack-stopping toughness of the crack-stopping steel is predicted subsequently, obtaining the ductile-brittle transition temperature ETT 50 of the impact test through a series of temperature dynamic tearing oscillometric impact tests, and substituting the ductile-brittle transition temperature ETT 50 into a correlation model to obtain the crack-stopping toughness.
According to the method for rapidly predicting the crack-stopping toughness of the crack-stopping steel based on the dynamic tearing test, disclosed by the invention, the dynamic tearing test is used for replacing a dual tensile test to predict the crack-stopping toughness of the crack-stopping steel, a correlation model of the crack-stopping toughness and the ductile-brittle transition temperature of an impact test is established, the crack-stopping toughness can be predicted through the correlation model and a series of temperature dynamic tearing oscillography impact tests in the subsequent research and development and trial processes of the crack-stopping steel, the method of the dynamic tearing oscillography impact test is mature, the equipment is simple, the period is short, the relevant standard specification is very perfect, and the test cost is low; 2. the dynamic tearing oscillography impact test sample has small size, does not need large-scale rolling, and saves a large amount of materials and processing cost; 3. the crack-arrest toughness can be predicted more accurately.
Further, the correlation model is as follows:
In the above formula, K ca is N/mm 1.5,ETT50, t is the plate thickness, and t is mm.
Further, in step S1, by performing a dual tensile test on the crack-arrest steels with different thicknesses and different strength grades, the crack-arrest toughness K ca measured by the dual tensile test on the crack-arrest steels with different thicknesses and different strength grades is obtained.
Further, the dimensions of the specimen in the double tensile test were 500mm×500mm×the original plate thickness.
Further, in step S1, the crack-arrest toughness K ca measured under the double tensile test of the crack-arrest steels of different thicknesses and different strength grades is obtained from the existing crack-arrest steel data.
Further, step S2 includes the steps of:
s21, carrying out a series of temperature dynamic tearing oscillography impact tests on the crack-arrest steels with different thicknesses and different strength grades in the step S1 to obtain a load-displacement curve and expansion work at each temperature;
s22, based on the expansion work, obtaining a ductile-brittle transition curve of each crack-stopper steel and a ductile-brittle transition temperature ETT 50 of an impact test through data fitting.
Further, in step S21, the test pieces of the series temperature dynamic tear oscillometric impact test have dimensions of 16mm by 40mm by 180mm.
Further, in step S21, the temperature range of the series temperature dynamic tear oscillometric impact test is-196-0 ℃.
Further, in step S22, based on the expansion work, the ductile-brittle transition curve of each crack-stopper steel and the impact test ductile-brittle transition temperature ETT 50 are obtained by Boltzmann function fitting.
Further, in step S3, a correlation model of the crack arrest toughness K ca and the impact test ductile-brittle transition temperature ETT 50 is established by a regression analysis method and correction with plate thickness factors.
The influence of the plate thickness factors on the large-size double tensile test and the small-size DT test is comprehensively considered, the prediction precision is further improved through the correlation model of the plate thickness factor correction large-size and small-size test, and the error can meet the requirements of material research and development and trial production stages.
Compared with the prior art, the method for rapidly predicting the crack-stopping toughness of the crack-stopping steel based on the dynamic tearing test has the following beneficial effects:
The method for rapidly predicting the crack-stopping toughness of the crack-stopping steel based on the dynamic tearing test can accurately predict the crack-stopping toughness; the original plate thickness dual tensile test and the small-size dynamic tearing oscillography impact test react to the changes of material fracture and crack stopping performance along with temperature, belong to the fracture category of ship hull crack stopping steel, have internal connection in the aspects of crack initiation, crack extension and crack termination, further improve the prediction precision through the plate thickness factor correction size and size test correlation model, and the error can meet the requirements of material research, development and trial production stages.
According to the method for rapidly predicting the crack-stopping toughness of the crack-stopping steel based on the dynamic tearing test, disclosed by the invention, the sample size is small, large-scale rolling is not needed, and a large amount of materials and processing cost are saved; the dynamic tearing test sample has small size and easy processing, a group of temperature dynamic tearing test needs only 16 samples at least, the weight is not more than 15 kg, the dynamic tearing test sample is suitable for small-scale anti-cracking steel in the research and development or trial production stage, and the double tensile test needs at least 4 pairs of test boards with 500mm multiplied by the original plate thickness.
The method for rapidly predicting the crack-stopping toughness of the crack-stopping steel based on the dynamic tearing test is mature and simple, short in period, low in cost and capable of saving a large amount of research expenses; the DT oscillography impact test method is mature, the equipment is simple, the relevant standard specification is very perfect, the test cost is low, the double tensile test is required to be carried out on a large-tonnage wide plate tensile tester, a large amount of welding materials are required to be consumed for test tool assembly, and a large amount of cooling liquid is required to establish a temperature field during the test; the impact test replaces the double tensile test, the period is shortened from a few months to a few days, and the cost is reduced from hundreds of thousands to thousands of yuan.
Drawings
FIG. 1 is a schematic illustration of a dual tensile test according to an embodiment of the present invention;
FIG. 2 is an actual photograph of a specimen of a double tensile test according to an embodiment of the present invention;
FIG. 3 is a schematic diagram of a method for determining crack arrest temperature in a dual tensile test according to an embodiment of the present invention;
FIG. 4 is a graph of a calculation model of crack arrest toughness interpolation for a dual tensile test according to an embodiment of the present invention;
FIG. 5 is a schematic front view of a test specimen for dynamic tear testing according to an embodiment of the present invention;
FIG. 6 is a schematic side view of a test specimen of a dynamic tear test according to an embodiment of the present invention;
FIG. 7 is a photograph of a typical fracture morphology of a sample of a dynamic tear test according to an embodiment of the present invention;
FIG. 8 is a load-displacement graph of a dynamic tear test according to an embodiment of the present invention;
FIG. 9 is a schematic diagram of typical ductile-brittle transition curves for the dynamic tear test according to the embodiment of the present invention;
FIG. 10 is a graph showing a correlation between crack arrest toughness and impact test ductile-brittle transition temperature without considering sheet thickness according to an embodiment of the present invention;
FIG. 11 is a graph showing a correlation model between crack arrest toughness and impact test ductile-brittle transition temperature with plate thickness taken into account according to an embodiment of the present invention;
FIG. 12 is a graph comparing actual and predicted values of crack-stopping toughness of a crack-stopping steel according to an embodiment of the present invention.
Reference numerals illustrate:
1. A main stretching plate; 2. a cracking plate; 3. a gradient temperature field.
Detailed Description
It should be noted that, without conflict, the embodiments of the present invention and features of the embodiments may be combined with each other. The description of "first," "second," etc. in embodiments of the present invention is for descriptive purposes only and is not to be construed as indicating or implying a relative importance or number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include at least one such feature. In addition, the technical solutions of the embodiments may be combined with each other, but it is necessary to base that the technical solutions can be realized by those skilled in the art, and when the technical solutions are contradictory or cannot be realized, the combination of the technical solutions should be considered to be absent and not within the scope of protection claimed in the present invention.
The invention will be described in detail below with reference to the drawings in connection with embodiments.
In the prior art, the fracture toughness is measured by adopting a ladder temperature type dual tensile test, on one hand, the dual tensile test at least needs 4 pairs of test boards with the thickness of 500mm multiplied by the original board thickness, and the test boards need large-scale rolling, and the material and processing cost are high; on the other hand, the double tensile test is required to be carried out on a 5000-ton large-scale tensile testing machine, a large amount of welding materials are required to be consumed for testing tool assembly, a large amount of cooling liquid is required to be consumed when a temperature field is established, the testing period is long, and the cost is high.
To solve this problem, the applicant conceived that if the crack-stopping toughness can be rapidly predicted by using a commonly used small-sized test in the development and trial-production stages of the crack-stopping steel, it is remarkably effective in development progress and cost.
Dynamic tear test (DYNAMIC TEAR TEST, abbreviated as DT) was proposed by the United states naval institute in 1960, and the sample format used for the dynamic tear test is shown in FIGS. 5 and 6, with standard sample sizes of 16mm by 40mm by 180mm. Impact load is applied to the sample by using a hammer head, and the energy change in the impact process and analysis of fracture microscopic morphology are recorded, as shown in fig. 7. The dynamic tear test uses a larger specimen size and a higher notch sharpness than the Charpy impact test, and the measured results are closer to the actual use performance. Previous research results also indicate that there is a correlation between Dynamic Tear Energy (DTE) and plane strain fracture toughness KIC. In the dynamic tearing oscillometric test process, the impact load-displacement curve of the sample in the deformation and fracture process is recorded by an instrument, and energy in different deformation and fracture stages can be obtained, namely crack initiation energy and expansion energy in the dynamic tearing process can be obtained, and a typical load-displacement curve is shown in fig. 8. The energy corresponding to the maximum load point Pm is generally referred to as the cracking work, and the energy after the point Pm is referred to as the expansion work, such as the energy corresponding to the hatched area in fig. 8, and the ductile-brittle transition characteristic temperature ETT 50 can be obtained according to the data of the expansion work changing with temperature. The expansion work shows the capability of the material for preventing crack expansion, and the higher the expansion work is, the stronger the crack blocking effect is, so that the expansion work can be used for indirectly representing the crack stopping performance. If the correlation between the crack-stopping toughness of the dual tensile test and the expansion work of the dynamic tearing test can be established, the crack-stopping toughness of the crack-stopping steel can be rapidly evaluated through the small-size dynamic tearing test, and the method has important guiding significance for accelerating the research and the application of the crack-stopping steel. For the technology, no published report exists at present, and no corresponding patent is published.
The invention particularly relates to a method for predicting the crack-arrest toughness of hull structural steel by a dynamic tear test (DT) instead of a double tensile test.
The invention aims to provide a method for rapidly predicting the crack-stopping toughness of the crack-stopping steel through a simple dynamic tearing oscillography impact test, which can meet the initial evaluation of the crack-stopping toughness in the research and development and trial production stages of the crack-stopping steel and provides important basic input for realizing the large-scale application of the crack-stopping steel and improving the operation safety of an oversized container ship.
In the process of designing and developing the crack-arrest steel, testing the crack-arrest toughness is the core for evaluating the development effect, and the invention provides a rapid prediction method of the crack-arrest performance mainly based on the requirement.
The purpose of the invention is realized in the following way: carrying out double tensile tests of the crack-stopping steel with different thickness and different strength grades to obtain a large number of crack-stopping toughness K ca or obtain the crack-stopping toughness K ca based on the existing crack-stopping steel data; aiming at the crack-arrest steel with each specification and strength grade, a series of temperature DT oscillography impact tests are carried out, and data such as load-displacement curves, expansion work and the like at each temperature are obtained. Obtaining a ductile-brittle transition curve and a transition temperature ETT 50 according to the expansion work; further analyzing the correlation between the crack-arrest toughness K ca and the transition temperature ETT 50, and taking the influence of plate thickness factors into consideration, establishing a correlation model, and further realizing the rapid prediction of the crack-arrest toughness through ETT 50.
Specifically, as shown in fig. 1 to 12, the invention provides a method for rapidly predicting the crack-stopping toughness of a crack-stopping steel based on a dynamic tearing test, which comprises the following steps:
S1, obtaining crack-arrest toughness K ca of crack-arrest steels with different thicknesses and different strength grades, which are measured under a double tensile test;
S2, carrying out a series of temperature dynamic tearing oscillometric impact tests on the crack-arrest steels with different thicknesses and different strength grades in the step S1 to obtain impact test ductile-brittle transition temperatures ETT 50 at each temperature;
S3, establishing a correlation model of crack arrest toughness K ca and impact test ductile-brittle transition temperature ETT 50;
s4, when the crack-stopping toughness of the crack-stopping steel is predicted subsequently, obtaining the ductile-brittle transition temperature ETT 50 of the impact test through a series of temperature dynamic tearing oscillometric impact tests, and substituting the ductile-brittle transition temperature ETT 50 into a correlation model to obtain the crack-stopping toughness.
According to the method for rapidly predicting the crack-stopping toughness of the crack-stopping steel based on the dynamic tearing test, the steps S1-S4 are related, the crack-stopping toughness of the crack-stopping steel is predicted by the dynamic tearing test instead of the dual tensile test, a correlation model of the crack-stopping toughness and the ductile-brittle transition temperature of the impact test is established, the crack-stopping toughness can be predicted by the correlation model and the series temperature dynamic tearing oscillometric impact test in the subsequent research and development and trial production process of the crack-stopping steel, the method for the first dynamic tearing oscillometric impact test is mature, the equipment is simple, the period is short, the correlation standard specification is very perfect, and the test cost is low; 2. the dynamic tearing oscillography impact test sample has small size, does not need large-scale rolling, and saves a large amount of materials and processing cost; 3. the crack-arrest toughness can be predicted more accurately.
Specifically, the correlation model is as follows:
In the above formula, K ca is N/mm 1.5,ETT50, t is the plate thickness, and t is mm.
Specifically, in step S1, the crack-arrest toughness K ca measured under the double tensile test of the crack-arrest steels with different thicknesses and different strength grades is obtained from the existing crack-arrest steel data.
More specifically, in step S1, according to the chinese classification society specification "application guidelines for high strength thick plates for ships (2024), at least four groups of effective crack-arresting toughness values K ca and T k are obtained by performing a ladder-temperature type double tensile test on 80-100 mm EH40 and EH47 crack-arresting steels; as shown in FIG. 1, a gradient type temperature field is established in the double tensile test, namely, a cold source is applied to the upper part of the shadow area in FIG. 1, and a heat source is applied to the lower part of the shadow area, so that a temperature gradient of 0.25 ℃/mm to 0.35 ℃/mm is formed. After the test is finished, the crack is expanded to a certain length a, and then the expansion is stopped, and the crack stop temperature T k at the crack length a can be obtained according to the temperature gradient, as shown in figure 3. K ca corresponding to the temperature T k is calculated according to the formula (1). Fitting the four obtained valid sets of K ca and T k values according to equation (2) to obtainAs shown in fig. 4.
In the above formula, σ is the applied stress level, a is the crack length, W s is the sample width, K 0 and T 0 are the material parameters, and T is the temperature.
Specifically, as shown in FIG. 1, the sample size of the double tensile test was 500 mm. Times.500 mm. Times.the original plate thickness.
Specifically, step S2 specifically includes: according to GB/T5482-2007 'method for dynamic tear test of metallic materials', sampling and processing the same batch of test boards of each piece of crack-stopping steel in the step S1 into standard DT test pieces, carrying out a series of temperature dynamic tear oscillometric impact tests, wherein the test pieces have the dimensions of 16mm multiplied by 40mm multiplied by 180mm, carrying out the series of temperature dynamic tear oscillometric impact tests, obtaining dynamic tear expansion work at different temperatures when the temperature range of the series of temperature dynamic tear oscillometric impact tests is-196-0 ℃, drawing a (temperature, expansion work) scatter diagram, and obtaining the ductile-brittle transition temperature ETT 50 of each piece of steel based on the expansion work through data fitting according to Boltzmann function, as shown in formula (3).
Specifically, in step S3, the influence of the plate thickness factor on the large-size dual tensile test and the small-size DT test is comprehensively considered, and the correlation model of the crack arrest toughness K ca and the impact test ductile-brittle transition temperature ETT 50 is established by modifying the plate thickness factor by a regression analysis method.
The influence of the plate thickness factors on the large-size double tensile test and the small-size DT test is comprehensively considered, the prediction precision is further improved through the correlation model of the plate thickness factor correction large-size and small-size test, and the error can meet the requirements of material research and development and trial production stages.
Example 1
According to the method for rapidly predicting the crack-arrest toughness, 16 groups of crack-arrest steels are selected for testing, corresponding crack-arrest toughness and impact test ductile-brittle transition temperature are measured, and a correlation model of the crack-arrest toughness and the impact test ductile-brittle transition temperature is constructed.
Specifically, the embodiment provides a method for rapidly predicting the crack-arrest toughness of the crack-arrest steel based on a dynamic tearing test, which comprises the following steps:
S1, as shown in Table 1, 16 groups of EH40 or EH47 crack-arrest steels are selected, double tensile tests of 4 samples are carried out on each group, and crack-arrest toughness at-10 ℃ is obtained through fitting;
S2, sampling from the same test plate of the double tensile test to perform a series of dynamic tearing oscillometric impact test at the temperature ranging from 0 ℃ to-196 ℃, and fitting by using a Boltzmann function to obtain a ductile-brittle transition curve based on expansion work and a ductile-brittle transition temperature ETT 50 temperature of the impact test of each group of steel, wherein a typical temperature transition curve is shown in FIG. 9; the specification, crack-stopping toughness and impact test ductile-brittle transition temperature results of each group of crack-stopping steels are shown in Table 1.
Table 1 test results
S3, adopting a regression analysis method to directly carry out regression analysis on the crack arrest toughness K ca and the impact test ductile-brittle transition temperature ETT 50, and finding that the correlation coefficient is lower, wherein the correlation coefficient R=0.71, and the result is shown in fig. 10 and formula (4); considering the correction of the plate thickness factor, dividing K ca and ETT 50 by the plate thickness t 1.5, respectively, and performing linear regression again to obtain a correlation model with a correlation coefficient of 0.9, and the result is shown in fig. 11, and the correlation model is shown in formula (5).
In the above formula, K ca units are N/mm 1.5, the impact test ductile-brittle transition temperature ETT 50 units are DEG C, t is the plate thickness, and t is mm.
S4, when the crack-stopping toughness of the crack-stopping steel is predicted subsequently, obtaining the ductile-brittle transition temperature ETT 50 of the impact test through a series of temperature dynamic tearing oscillometric impact tests, and substituting the ductile-brittle transition temperature ETT 50 into a correlation model to obtain the crack-stopping toughness.
In this embodiment, the impact test ductile-brittle transition temperature ETT 50 of step S2 is substituted into the correlation model to obtain the predicted value of crack-arrest toughness.
Crack arrest toughness K ca in Table 1 is an actual measurement, and the predicted value and the actual measurement are compared, as shown in FIG. 12.
From FIG. 12, it can be seen that the fracture toughness K ca is predicted by the impact test ductile-brittle transition temperature ETT 50 and the correlation model, the prediction accuracy is high, the error is not more than 1000N/mm 1.5 at maximum, and the requirements of the material research and development and trial production stages can be met.
Although the present invention is disclosed above, the present invention is not limited thereto. Various changes and modifications may be made by one skilled in the art without departing from the spirit and scope of the invention, and the scope of the invention should be assessed accordingly to that of the appended claims.
Claims (10)
1. The method for rapidly predicting the crack-arrest toughness of the crack-arrest steel based on the dynamic tearing test is characterized by comprising the following steps of:
S1, obtaining crack-arrest toughness K ca of crack-arrest steels with different thicknesses and different strength grades, which are measured under a double tensile test;
S2, carrying out a series of temperature dynamic tearing oscillometric impact tests on the crack-arrest steels with different thicknesses and different strength grades in the step S1 to obtain impact test ductile-brittle transition temperatures ETT 50 at each temperature;
S3, establishing a correlation model of crack arrest toughness K ca and impact test ductile-brittle transition temperature ETT 50;
s4, when the crack-stopping toughness of the crack-stopping steel is predicted subsequently, obtaining the ductile-brittle transition temperature ETT 50 of the impact test through a series of temperature dynamic tearing oscillometric impact tests, and substituting the ductile-brittle transition temperature ETT 50 into a correlation model to obtain the crack-stopping toughness.
2. The method for rapidly predicting crack-arrest toughness of a crack-arrest steel based on a dynamic tear test as claimed in claim 1, wherein the correlation model is as follows:
；
In the above formula, K ca is N/mm 1.5,ETT50, t is the plate thickness, and t is mm.
3. The method for rapidly predicting the crack-arrest toughness of the crack-arrest steel based on the dynamic tear test according to claim 2, wherein in the step S1, the crack-arrest toughness K ca measured by the crack-arrest steel with different thickness and different strength grades under the double tensile test is obtained by performing the double tensile test on the crack-arrest steel with different thickness and different strength grades.
4. A method for rapidly predicting crack-arrest toughness of a crack-arrest steel based on a dynamic tear test as claimed in claim 3, wherein the dimensions of the specimen of the dual tensile test are 500mm x original plate thickness.
5. The method for rapidly predicting the crack-arrest toughness of the crack-arrest steel based on the dynamic tear test according to claim 2, wherein in the step S1, the crack-arrest toughness K ca measured by the double tensile test of the crack-arrest steel with different thickness and different strength grades is obtained through the existing crack-arrest steel data.
6. The method for rapidly predicting crack-arrest toughness of a crack-arrest steel based on a dynamic tear test as claimed in claim 4 or 5, wherein the step S2 comprises the steps of:
s21, carrying out a series of temperature dynamic tearing oscillography impact tests on the crack-arrest steels with different thicknesses and different strength grades in the step S1 to obtain a load-displacement curve and expansion work at each temperature;
s22, based on the expansion work, obtaining a ductile-brittle transition curve of each crack-stopper steel and a ductile-brittle transition temperature ETT 50 of an impact test through data fitting.
7. The method for rapidly predicting crack-arrest toughness of a crack-arrest steel based on a dynamic tear test as claimed in claim 6, wherein in the step S21, the test pieces of the series temperature dynamic tear oscillometric impact test have dimensions of 16mm x 40mm x 180mm.
8. The method for rapidly predicting the crack-arrest toughness of the crack-arrest steel based on the dynamic tear test according to claim 7, wherein in the step S21, the temperature range of the series temperature dynamic tear oscillometric impact test is-196-0 ℃.
9. The method for rapidly predicting crack-arrest toughness of crack-arrest steel based on the dynamic tear test according to claim 8, wherein in step S22, the ductile-brittle transition curve of each crack-arrest steel and the impact test ductile-brittle transition temperature ETT 50 are obtained by Boltzmann function fitting based on the expansion work.
10. The method for rapidly predicting crack-arrest toughness of a crack-arrest steel based on a dynamic tear test according to claim 9, wherein in step S3, a correlation model of crack-arrest toughness K ca and impact test ductile-brittle transition temperature ETT 50 is established by a regression analysis method and correction with plate thickness factors.
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