CN108356437B - System and method for detecting weldability of surface of martensitic steel hot stamping forming part - Google Patents
System and method for detecting weldability of surface of martensitic steel hot stamping forming part Download PDFInfo
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- CN108356437B CN108356437B CN201810144094.8A CN201810144094A CN108356437B CN 108356437 B CN108356437 B CN 108356437B CN 201810144094 A CN201810144094 A CN 201810144094A CN 108356437 B CN108356437 B CN 108356437B
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K31/00—Processes relevant to this subclass, specially adapted for particular articles or purposes, but not covered by only one of the preceding main groups
- B23K31/12—Processes relevant to this subclass, specially adapted for particular articles or purposes, but not covered by only one of the preceding main groups relating to investigating the properties, e.g. the weldability, of materials
Abstract
The invention discloses a system for detecting the surface weldability of a martensitic steel hot stamping part, which comprises an electrode line concentration module (1), wherein the input end of the electrode line concentration module (1) is connected with a martensitic steel hot stamping part (6), the output end of the electrode line concentration module (1) is connected with the input end of a resistance detection unit (2), the output end of the resistance detection unit (2) is in communication connection with an industrial personal computer (3), the output end of the industrial personal computer (3) is connected with the input end of a display module (4), and the industrial personal computer (3) is also in communication connection with a feedback unit (5). The invention also discloses a detection method of the system for detecting the weldability of the surface of the martensitic steel hot stamping part, and the system has the advantages of low cost, high accuracy, easy realization and high reliability, and can be used for quality detection of a full-automatic production line.
Description
Technical Field
The invention relates to a system and a method for detecting the surface weldability of a martensitic steel hot stamping part, and belongs to the technical field of martensitic steel hot stamping.
Background
With the increasing requirements for safety and light weight in the fields of automobiles and rail transportation, martensitic steels with ultrahigh strength are receiving more and more attention. The martensite steel mainly has a martensite structure, the tensile strength of the martensite steel can reach 1500MPa, and the strength is enhanced by reducing the thickness of the steel plate on the premise of ensuring the safety, so that the martensite steel is widely applied to the automobile and rail transit industries. However, cold-stamping of martensitic steels presents problems of cracking, spring back and thinning, limiting the use of these materials.
The hot stamping forming technology is that low-alloy martensitic steel is heated to austenitizing temperature, is kept warm until the low-alloy martensitic steel is completely austenitized, is quickly transferred into a die with a cooling system for stamping forming, and simultaneously, a quick and uniform quenching process is completed in the die to obtain a uniform martensitic structure, so that a low-strength steel plate is converted into a component with ultrahigh strength (the tensile strength is more than or equal to 1500MPa, and the elongation is about 6%). The hot forming technology has the advantages of small forming pressure, high strength of formed parts, small resilience and high dimensional accuracy, thereby being widely applied.
The common production flow of the existing hot stamping forming part is as follows: blanking → heat preservation to austenitizing → rapid transfer to a die → hot stamping forming → oxide scale removal → laser trimming → welding and other subsequent processes. Although Al-Si and Zn-based hot forming high-temperature protective coatings are prepared on the surface of the martensitic steel in advance at present, an oxide layer is likely to be generated on the surface of the martensitic steel in the actual hot forming process, the welding performance of martensitic steel parts is further seriously affected, and finally the working safety and the service life of welded components are seriously deteriorated. At present, most of welding methods adopted by hot forming parts are resistance welding, the degree of influence of an oxide layer on the surfaces of the hot forming parts on welding is large, whether the welding process can carry out reliable welding or not can be judged only by visual confirmation of the appearances of the parts, and the welding rejection rate of the hot forming parts is high. Therefore, a system and a method for detecting the weldability of the surface of a martensitic steel hot stamping part are urgently needed to be found.
Disclosure of Invention
The invention aims to solve the technical problem that the invention provides a system and a method for detecting the weldability of the surface of a martensitic steel hot stamping part, the detection system and the detection method can be used for conveniently and quickly identifying the degree of an oxide layer covered on the surface of the part (the resistance value of each welding point), and the weldability of the part can be directly judged according to the quantitative data of the critical resistance value, so that the system and the method have the advantages of low cost, high accuracy, easy realization and high reliability, and can be used for quality detection of a full-automatic production line.
In order to solve the technical problems, the technical scheme adopted by the invention is as follows:
the system for detecting the surface weldability of the martensitic steel hot stamping part comprises an electrode line concentration module, wherein the input end of the electrode line concentration module is connected with the martensitic steel hot stamping part, the output end of the electrode line concentration module is connected with the input end of a resistance detection unit, the output end of the resistance detection unit is in communication connection with an industrial personal computer, the output end of the industrial personal computer is connected with the input end of a display module, and the industrial personal computer is also in communication connection with a feedback unit.
The electrode wire collecting module comprises an electrode wire collecting body, wherein a plurality of groups of positive and negative electrode pairs are arranged on the electrode wire collecting body, each group of positive and negative electrode pairs is respectively connected with different points to be welded on the martensitic steel hot stamping part, vertical sliding rails are symmetrically arranged on two sides of the electrode wire collecting body, a contact sliding block is connected between the two vertical sliding rails, contacts used for being in contact with the positive and negative electrode pairs are arranged on the contact sliding block, and the contact sliding block is connected with an electric driving module.
And a transverse sliding rail is connected between the two vertical sliding rails, and the contact sliding block is arranged on the transverse sliding rail.
The electric driving module comprises a vertical electric driving mechanism and a transverse electric driving mechanism, and the vertical electric driving mechanism and the transverse electric driving mechanism respectively comprise a servo motor, a transmission mechanism and a motion control module.
The transmission mechanism comprises a first sliding block arranged on the vertical sliding rail and a second sliding block arranged on the transverse sliding rail, the first sliding block is connected with the transverse sliding rail, the second sliding block is connected with the contact sliding block, the first sliding block and the second sliding block are respectively connected with the servo motors, and the motion control module is respectively in communication connection with the two servo motors.
And a memory is arranged in the industrial personal computer.
The feedback unit comprises an alarm.
The detection method of the system for detecting the weldability of the surface of the martensitic steel hot stamping forming part comprises the following steps:
s01, connecting the electrode line concentration module, and respectively connecting each group of positive and negative electrode pairs to the upper and lower surfaces of each to-be-welded point of the martensitic steel hot stamping forming part;
s02, detecting a pad resistance value: sequentially detecting each welding point resistance by using a contact sliding block on the electrode wiring module through a resistance detection unit, and automatically sliding the contact sliding block to the next group of positive and negative electrode pairs after one welding point resistance test is finished;
s03, output resistance value: the resistance value of each welding point measured by the resistance detection unit is transmitted to a memory of an industrial personal computer for storage, and the industrial personal computer converts the measured resistance value into an analog signal and outputs the analog signal on a display screen of a display module; the other side of the industrial personal computer judges the measured resistance value, and when the resistance is greater than the critical resistance, the industrial personal computer activates a feedback unit to give an alarm and the test is terminated; when the resistance is smaller than the critical resistance, the weldability of the welding point is qualified, and the next welding point is continuously tested;
and S04, feeding back a detection result: the feedback unit processes the judgment result of the industrial personal computer, and when the weldability of the welding point is qualified, S02-S04 is repeated to detect the next welding point; when the weldability of the welding point is unqualified, an alarm in the feedback unit sounds, the detection is terminated, and the martensitic steel hot stamping forming part is transmitted to an unqualified part area.
The invention has the following beneficial effects:
1. the system for detecting the weldability of the surface of the martensitic steel hot stamping part provided by the invention can realize full-automatic detection of the weldability of the surface welding point of the martensitic steel hot stamping part by using the sliding mechanism of the electrode wire collecting module and the resistance detection unit. The system is simple and easy to realize, low in equipment cost, convenient to operate and good in test stability, and can be used for online quality detection of a production line.
2. The detection method of the system for detecting the weldability of the surface of the martensitic steel hot stamping part, which is provided by the invention, introduces the feedback unit, can be used for quickly and qualitatively judging the weldability of the welding point of the martensitic steel hot stamping part, can be used for timely pre-judging the surface quality of the hot stamping part, can be used for greatly reducing the incidence rate of the problem of poor surface quality of the hot stamping part, ensures the yield of the hot stamping part and has higher engineering application value.
Drawings
FIG. 1 is a schematic structural view of the present invention;
FIG. 2 is a schematic structural view of a contact slider according to the present invention;
FIG. 3 is a flow chart of the operation of the present invention;
FIG. 4 is a schematic structural diagram of a B-pillar component of an automobile according to an embodiment of the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more clear, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. The specific embodiments described herein are merely illustrative of the invention and are not intended to be limiting.
As shown in fig. 1-2, the system for detecting the weldability of the surface of a part formed by hot stamping of martensitic steel comprises an electrode line concentration module 1, wherein the input end of the electrode line concentration module 1 is connected with a part 6 formed by hot stamping of martensitic steel, the output end of the electrode line concentration module 1 is connected with the input end of a resistance detection unit 2, the output end of the resistance detection unit 2 is in communication connection with an industrial personal computer 3, the output end of the industrial personal computer 3 is connected with the input end of a display module 4, and the industrial personal computer 3 is also in communication connection with a feedback unit 5.
The electrode wire collecting module 1 comprises an electrode wire collecting body 7, a plurality of groups of positive and negative electrode pairs 10 are arranged on the electrode wire collecting body 7, each group of positive and negative electrode pairs 10 is respectively connected with different points to be welded on the martensite steel hot stamping forming part 6, vertical sliding rails 8 are symmetrically arranged on two sides of the electrode wire collecting body 7, a contact sliding block 9 is connected between the two vertical sliding rails 8, contacts used for being in contact with the positive and negative electrode pairs 10 are arranged on the contact sliding block 9, and the contact sliding block 9 is connected with an electric driving module.
And a transverse sliding rail 11 is connected between the two vertical sliding rails 8, and the contact sliding block 9 is arranged on the transverse sliding rail 11.
The electric driving module comprises a vertical electric driving mechanism and a transverse electric driving mechanism, and the vertical electric driving mechanism and the transverse electric driving mechanism respectively comprise a servo motor, a transmission mechanism and a motion control module.
The transmission mechanism comprises a first sliding block arranged on the vertical sliding rail 8 and a second sliding block arranged on the transverse sliding rail 11, the first sliding block is connected with the transverse sliding rail 11, the second sliding block is connected with the contact sliding block 9, the first sliding block and the second sliding block are respectively connected with the servo motors, and the motion control module is respectively in communication connection with the two servo motors. When the resistance test of one welding point is finished, the contact sliding block 9 moves to the next positive and negative electrode pair 10 along the vertical sliding rail 8 and the transverse sliding rail 11 under the electric drive; and stopping the sliding mechanism until the last group of positive and negative electrode pairs 10 is moved, and sending a detection end signal to the industrial personal computer 3.
And a memory is arranged in the industrial personal computer 3.
The feedback unit 5 comprises an alarm.
As shown in fig. 3, the detection method of the system for detecting the weldability of the surface of the martensitic steel hot stamping forming part comprises the following steps:
s01, connecting the electrode line concentration module 1, and respectively connecting each group of positive and negative electrode pairs 10 to the upper and lower surfaces of each to-be-welded point of the martensitic steel hot stamping forming part 6;
s02, detecting a pad resistance value: the contact slide block 9 on the electrode wire collecting module 1 is used for sequentially detecting each welding point resistance through the resistance detection unit 2, and after one welding point resistance test is finished, the contact slide block 9 automatically slides to the next group of positive and negative electrode pairs 10;
s03, output resistance value: the resistance value of each welding point measured by the resistance detection unit 2 is transmitted to a memory of the industrial personal computer 3 for storage, and on one hand, the industrial personal computer 3 converts the measured resistance value into an analog signal and outputs the analog signal on a display screen of the display module 4; the other side of the industrial personal computer 3 judges the measured resistance value, and when the resistance is larger than the critical resistance, the industrial personal computer 3 activates the feedback unit 5 to give an alarm, and the test is terminated; when the resistance is smaller than the critical resistance, the weldability of the welding point is qualified, and the next welding point is continuously tested;
and S04, feeding back a detection result: the feedback unit 5 processes the judgment result of the industrial personal computer 3, and when the weldability of the welding point is qualified, S02-S04 is repeated to detect the next welding point; when the weldability of the welding point is not qualified, an alarm in the feedback unit 5 sounds, the detection is terminated, and the martensitic steel hot-stamped forming part 6 is transmitted to the unqualified part area.
The critical resistance value is 15m omega.
The resistance detection unit 2 receives the electrical signal transmitted by the contact slider 9 on one hand, so as to test the resistance value of the welding point; and on the other hand, the measured resistance value of the welding point is transmitted to the industrial personal computer 3 for storage.
As shown in fig. 4, the martensitic steel hot-stamped component 6 in this example is a martensitic steel hot-stamped B-pillar component for an automobile, and has a thickness of 1.5 mm.
It is noted that the critical resistance value of the martensitic steel hot-stamped part 6 is related to its material and sheet thickness. The critical resistance values of different thermoformed parts also vary. The foregoing shows and describes the general principles, essential features, and advantages of the invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are described in the specification and illustrated only to illustrate the principle of the present invention, but that various changes and modifications may be made therein without departing from the spirit and scope of the present invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.
Claims (7)
1. Martensite steel hot stamping forming part surface weldability detecting system which characterized in that: the device comprises an electrode line concentration module (1), wherein the input end of the electrode line concentration module (1) is connected with a martensitic steel hot stamping part (6), the output end of the electrode line concentration module (1) is connected with the input end of a resistance detection unit (2), the output end of the resistance detection unit (2) is in communication connection with an industrial personal computer (3), the output end of the industrial personal computer (3) is connected with the input end of a display module (4), and the industrial personal computer (3) is also in communication connection with a feedback unit (5);
the electrode wire collecting module (1) comprises an electrode wire collecting body (7), a plurality of groups of positive and negative electrode pairs (10) are arranged on the electrode wire collecting body (7), each group of positive and negative electrode pairs (10) is respectively connected with different welding points on the martensitic steel hot stamping forming part (6), vertical sliding rails (8) are symmetrically arranged on two sides of the electrode wire collecting body (7), a contact sliding block (9) is connected between the vertical sliding rails (8), contacts used for being in contact with the positive and negative electrode pairs (10) are arranged on the contact sliding block (9), and the contact sliding block (9) is connected with an electric driving module.
2. The system for inspecting the weldability according to claim 1, wherein said system is characterized in that: a transverse sliding rail (11) is connected between the two vertical sliding rails (8), and the contact sliding block (9) is arranged on the transverse sliding rail (11).
3. The system for inspecting the weldability according to claim 2, wherein said system is characterized in that: the electric driving module comprises a vertical electric driving mechanism and a transverse electric driving mechanism, and the vertical electric driving mechanism and the transverse electric driving mechanism respectively comprise a servo motor, a transmission mechanism and a motion control module.
4. The system for inspecting the weldability according to claim 3, wherein said system is characterized in that: the transmission mechanism comprises a first sliding block arranged on the vertical sliding rail (8) and a second sliding block arranged on the transverse sliding rail (11), the first sliding block is connected with the transverse sliding rail (11), the second sliding block is connected with the contact sliding block (9), the first sliding block and the second sliding block are respectively connected with the servo motors, and the motion control module is respectively in communication connection with the two servo motors.
5. The system for inspecting the weldability according to claim 1, wherein said system is characterized in that: and a memory is arranged in the industrial personal computer (3).
6. The system for inspecting the weldability according to claim 1, wherein said system is characterized in that: the feedback unit (5) comprises an alarm.
7. The detection method of the system for detecting the weldability of the surface of the martensitic steel hot stamping forming part as claimed in claim 1 is characterized in that: the method comprises the following steps:
s01, connecting the electrode line concentration module (1), and respectively connecting each group of positive and negative electrode pairs (10) to the upper and lower surfaces of each to-be-welded point of the martensitic steel hot stamping forming part (6);
s02, detecting a pad resistance value: the resistance detection unit (2) is used for sequentially detecting the resistance of each welding point by using a contact sliding block (9) on the electrode wire collecting module (1), and after the resistance test of one welding point is finished, the contact sliding block (9) automatically slides to the next group of positive and negative electrode pairs (10);
s03, output resistance value: the resistance value of each welding point measured by the resistance detection unit (2) is transmitted to a memory of the industrial personal computer (3) for storage, and on one hand, the industrial personal computer (3) converts the measured resistance value into an analog signal to be output on a display screen of the display module (4); the other side of the industrial personal computer (3) judges the measured resistance value, and when the resistance is greater than the critical resistance, the industrial personal computer (3) activates the feedback unit (5) to alarm and the test is terminated; when the resistance is smaller than the critical resistance, the weldability of the welding point is qualified, and the next welding point is continuously tested;
and S04, feeding back a detection result: the feedback unit (5) processes the judgment result of the industrial personal computer (3), and when the weldability of the welding point is qualified, S02-S04 is repeated to detect the next welding point; when the weldability of the welding point is unqualified, an alarm in the feedback unit (5) sounds, the detection is terminated, and the martensitic steel hot stamping forming part (6) is transmitted to an unqualified part area.
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| CN201810144094.8A CN108356437B (en) | 2018-02-12 | 2018-02-12 | System and method for detecting weldability of surface of martensitic steel hot stamping forming part |
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| CN201810144094.8A CN108356437B (en) | 2018-02-12 | 2018-02-12 | System and method for detecting weldability of surface of martensitic steel hot stamping forming part |
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| CN108356437B true CN108356437B (en) | 2020-08-11 |
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2018
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