CN217277444U

CN217277444U - Disc sample for detecting dynamic and static tensile mechanical properties of explosive welding interface

Info

Publication number: CN217277444U
Application number: CN202220673900.2U
Authority: CN
Inventors: 陈鹏万; 周强; 刘睿
Original assignee: Beijing Institute of Technology BIT
Current assignee: Beijing Institute of Technology BIT
Priority date: 2022-03-25
Filing date: 2022-03-25
Publication date: 2022-08-23
Anticipated expiration: 2032-03-25

Abstract

The utility model relates to a detect disc sample that explosive welding interface dynamic and static tensile mechanical properties used belongs to interface mechanical properties test technical field. The disc sample is a circular composite plate formed by explosion welding two semicircular plates with the same size, a long-strip-shaped notch is machined in the center of the circular composite plate along the direction of an explosion welding interface, and the long-strip-shaped notch is a through hole penetrating through the thickness direction of the circular composite plate. The disc sample can ensure that failure in the dynamic loading process mainly occurs at an explosion welding interface, different process parameters of the composite plate explosion welding interface, dynamic and static tensile mechanical performance test and failure mechanism research under different application environment conditions can be realized by combining a Hopkinson pressure bar experimental device technology and an ultrahigh-speed digital camera, and the disc sample has important reference values for obtaining a good explosion welding composite plate, reducing the rejection rate of products, improving the quality of the products and prolonging the service life of the products.

Description

Disc sample for detecting dynamic and static tensile mechanical properties of explosive welding interface

Technical Field

The utility model relates to a detect disc sample that explosive welding interface dynamic and static tensile mechanical properties used belongs to interface mechanical properties test technical field.

Background

With the development of science and technology, explosive welding composite materials have been widely applied to the fields of industrial engineering such as aerospace, petroleum, chemical engineering, shipbuilding, machinery, electronics, electric power and the like. Wherein, explosion welding is an effective means which can combine metals with the same, similar or different physical and chemical properties, and even can combine products which can not be or are difficult to be made. The welding quality of explosive welding is mainly measured by tensile strength, shearing strength and bending strength of composite interfaces of different plates welded by explosive welding, the degree of crystallization embrittlement of the composite plate interfaces, the change of hardness and corrosion resistance of the composite plates and the like.

At present, the mechanical property research on the composite interface of the explosion-welded composite board is mainly in the aspect of static mechanics, and the dynamic mechanical property research is forced to be carried out by the condition that the size of the explosion-welded composite board is limited without a proper experimental method, so that the research on the dynamic and static tensile mechanical properties of the welding interface of the bimetal explosion-welded composite board in different application environments is rarely carried out. In industrial production application, the strength of a welding interface is an important standard for measuring the welding quality, and it is necessary to research the dynamic mechanical properties of an explosive welding interface and the fracture behavior and damage evolution mechanism under a dynamic loading condition.

SUMMERY OF THE UTILITY MODEL

To the problem that exists among the prior art, the utility model provides a detect disc sample that explosive bonding interface dynamic and static tensile mechanical properties used, through improving brazilian disc and processing rectangular shape incision at its surface center, combine hopkinson depression bar experimental apparatus technique (SHPB) and hypervelocity digital camera (DIC) to monitor explosive bonding interface's dynamic loading process, can realize the research to explosive bonding interface dynamic and static tensile mechanical behavior, improved explosive bonding interface dynamic and static tensile mechanical properties research level and range of application.

The purpose of the utility model is realized through the following technical scheme.

The disc sample is a circular composite plate formed by two semicircular plates with the same size through explosive welding, a strip-shaped notch is machined in the center of the circular composite plate along the direction of the explosive welding interface, and the strip-shaped notch is a through hole penetrating through the thickness direction of the circular composite plate.

The size of the strip-shaped notch can be correspondingly adjusted according to the performance of the plate in the disc sample, and mainly ensures that the tensile acting force is mainly concentrated at an explosive welding interface in the dynamic and static stretching process of the disc sample, so that the rupture failure can occur at the explosive welding interface; in addition, the two plates can be made of the same or different materials.

Further, the diameter of the disc sample is marked as D, the length of the elongated notch (i.e., the size of the notch processed in the direction along the explosive welding interface) is (0.3-0.5) D, and the width of the elongated notch (i.e., the size of the notch processed in the direction perpendicular to the direction along the explosive welding interface) is 0.2-1 mm.

Further, when the thickness of the disk sample is denoted by H, H is equal to or smaller than the diameter of the incident rod in the hopkinson pressure bar test apparatus, and more preferably, H is 5mm to 10 mm.

Further, D is 10mm to 20 mm.

Carrying out loading tests on the disc samples subjected to heat treatment at different temperatures under different strain rates by using a Hopkinson pressure bar experimental device, and monitoring dynamic loading and failure processes thereof by using an ultra-high speed digital camera, wherein the application points of the incident rod and the transmission rod on the disc samples are correspondingly positioned at two ends of an explosion welding interface; by carrying out subsequent processing on the data obtained by monitoring, the evaluation on the dynamic and static tensile mechanical properties and the failure mechanism of the interface of the explosion-welded composite plate after different heat treatments can be realized.

Has the advantages that:

the utility model relates to a disc sample can ensure that the inefficacy in dynamic loading process mainly takes place in explosion welding interface department, combine hopkinson depression bar experimental apparatus technique and hypervelocity digital camera moreover, can realize the different technological parameters of composite sheet material explosion welding interface and the test of dynamic and static tensile mechanical properties under different application environment conditions and the mechanism research that becomes invalid, for obtaining good explosion welding composite sheet and reducing the rejection rate of product, improve the quality and the life-span of product and have important reference value.

Drawings

FIG. 1 is a schematic view of the structure of a disc sample described in example 1.

Fig. 2 is a schematic diagram of the stress of the disc sample in the dynamic loading process in example 1.

Fig. 3 is a structural view of a device for performing a dynamic loading test on a test sample by using the hopkinson pressure bar experimental device technology.

The test device comprises a bullet 1, an incident rod 2, a strain gauge I3, a test sample 4, a strain gauge II 5, a transmission rod 6, a Wheatstone bridge II 7, an ultrahigh-speed digital camera 8, a Wheatstone bridge I9, a photoelectric switch 10, a lead 11, an ultra-dynamic strain gauge 12, an oscilloscope 13, a computer I14 and a computer II 15.

Detailed Description

The present invention will be further described with reference to the accompanying drawings and detailed description, wherein the process is conventional unless otherwise specified, and the starting materials are commercially available from the public without further specification. In addition, in the description of the present invention, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplification of the description, but do not indicate or imply that the device or element referred to must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present invention.

Example 1

The method is characterized in that a large-area titanium (TA2) -steel (Q235) explosion welding composite plate with the length, the width and the thickness of 750mm, 350mm and 130mm is taken as a research object, and the dynamic and static tensile mechanical properties of an explosion welding interface after different heat treatments are researched, and the method specifically comprises the following steps:

(1) cutting two circular small-area composite plates with the thickness of 5mm and the diameter of 16mm from the large-area composite plate, wherein the circular small-area composite plates comprise two titanium plates and two steel plates with the same size, and the explosive welding interfaces are positioned on the symmetry axis of the circular small-area composite plates;

wherein, a long strip-shaped notch is processed at the center of a round small-area composite plate along the direction of an explosion welding interface, the notch is a through hole penetrating through the thickness direction of the round small-area composite plate, the length of the notch (namely the size of the notch processed along the direction of the explosion welding interface) is 6mm, the width of the notch (namely the size of the notch processed along the direction vertical to the direction of the explosion welding interface) is 0.2mm, and then a half-disc sample is formed, as shown in fig. 1; the other round small-area composite plate is not processed, namely a strip-shaped notch is not processed and is used as a comparison sample;

(2) firstly, annealing a test sample 4 (comprising a disc sample and a comparison sample) (the annealing temperature is 500-1000 ℃), then polishing the test sample 4 to enable the surface smoothness of the test sample to reach 0.4-0.6, and then cleaning and airing the test sample with alcohol for later use;

(3) placing a test sample 4 between an incident rod 2 and a transmission rod 6 of a Hopkinson pressure bar experimental device, realizing loading of the test sample 4 at different strain rates by changing the length and the loading rate of a bullet 1, and monitoring dynamic loading and a failure process thereof by combining an ultra-high-speed digital camera 8, wherein the force application points of the incident rod 2 and the transmission rod 6 on the test sample 4 are correspondingly positioned at two ends of an explosion welding interface, as shown in figure 2;

as shown in fig. 3, the hopkinson pressure bar experimental device comprises a bullet 1, an incident rod 2, a strain gauge i 3, a strain gauge ii 5, a transmission rod 6, a wheatstone bridge ii 7, an ultra-high speed digital camera 8, a wheatstone bridge i 9, a photoelectric switch 10, an oscilloscope 13, an ultra-dynamic strain gauge 12, a computer i 14 and a computer ii 15; strain signals (incident strain and reflected strain) of an incident rod 2 are collected by a strain gauge I3 adhered to the incident rod 2, strain signals (transmitted strain) of a transmission rod 6 are collected by a strain gauge II 5 adhered to the transmission rod 6, information collected by the strain gauge I3 passes through a Wheatstone bridge I9 and information collected by the strain gauge II 5 passes through a Wheatstone bridge II 7, and then sequentially passes through an ultra-dynamic strain gauge 12 and an oscilloscope 13 and is recorded on a computer I14; the impact speed of the bullet 1 can be estimated through the distance between the two photoelectric switches 10 and the time difference between the bullet 1 and the two photoelectric switches 10; the computer I14 is used for recording and storing incident and transmission signals and controlling synchronous triggering of the ultra-high speed digital camera 8 so as to record the failure process of the test sample, the computer II 15 is used for controlling the ultra-high speed digital camera 8, and the ultra-high speed digital camera 8 is used for shooting the failure process of the test sample 4 under dynamic and static loading;

(4) and (3) carrying out subsequent processing on the experimental data acquired by the Hopkinson pressure bar experimental device and the change process data monitored by the ultra-high speed digital camera 8, thereby realizing the evaluation on the static and dynamic tensile mechanical properties and the failure mechanism of the explosion welding interface of the explosion welding titanium-steel composite plate after heat treatment.

The test specimen 4 failed during loading, wherein the disc specimen fractured from the explosion-welded interface under the induction of the elongated slit, while the control specimen without the elongated slit was failed at the interface, but at a position close to the base material. Elemental analysis (EDS) was performed on the fracture interface of the disc specimen to determine a percent Ti of 49.37% on the TA2 side and a percent Fe of 50.63% on the Q235 side, indicating that the specimen fractured from the explosion welded interface.

In summary, the above is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. Detect disc sample that explosive bonding interface dynamic and static tensile mechanical properties used, its characterized in that: the disc sample is a circular composite board formed by two semicircular plates with the same size through explosive welding, a strip-shaped notch is processed in the center of the circular composite board along the direction of an explosive welding interface, and the strip-shaped notch is a through hole penetrating through the thickness direction of the circular composite board.

2. The disc sample for detecting dynamic and static tensile mechanical properties of the explosive welding interface according to claim 1, characterized in that: and D represents the diameter of the disc sample, the length of the long-strip-shaped notch is (0.3-0.5) D, and the width of the long-strip-shaped notch is 0.2-1 mm.

3. The disc sample for detecting dynamic and static tensile mechanical properties of the explosive welding interface according to claim 1, characterized in that: the thickness of the disc sample is smaller than or equal to the diameter of an incident rod in the Hopkinson pressure bar experimental device.

4. The disc sample for detecting dynamic and static tensile mechanical properties of the explosive welding interface according to claim 3, wherein: the thickness of the disc sample is 5 mm-10 mm.

5. The disc sample for detecting dynamic and static tensile mechanical properties of an explosive welding interface according to any one of claims 1 to 4, wherein: the diameter of the disc sample is 10 mm-20 mm.