CN109647883B

CN109647883B - Method for preventing interface oxidation of rolled metal composite plate

Info

Publication number: CN109647883B
Application number: CN201910015251.XA
Authority: CN
Inventors: 黄强; 王道远; 黄贞益; 郭云侠; 马啸宇; 光剑锋; 黄华钦
Original assignee: Anhui University of Technology AHUT
Current assignee: Anhui University of Technology AHUT
Priority date: 2019-01-08
Filing date: 2019-01-08
Publication date: 2021-01-05
Anticipated expiration: 2039-01-08
Also published as: CN109647883A

Abstract

The invention discloses a method for preventing interface oxidation of a rolled metal composite plate, and belongs to the technical field of rolling of metal composite plates. In order to prevent the interface oxidation of the rolled metal composite plate, an exhaust hole is formed at the interface compounding position before heating and rolling, and then the exhaust hole is blocked by a sealing plug, so that the problem that the interface bonding rate is reduced due to the fact that air between the compounding interfaces expands when heated in the heating and rolling process of the composite plate, and the interface bonding strength of the composite plate is reduced can be solved; and the method has the advantages of simple structure, reasonable design and easy operation.

Description

Method for preventing interface oxidation of rolled metal composite plate

Technical Field

The invention belongs to the technical field of rolling of metal composite plates, and particularly relates to a method for preventing interface oxidation of a rolled metal composite plate.

Background

The metal composite plate is a metal matrix composite material obtained by forming firm metallurgical bonding at an interface after two or more layers of metal materials are subjected to certain specific processing technologies. Compared with single metal, the metal composite board not only has the advantages of respective components, but also can obtain physical, chemical and mechanical properties which are not possessed by a single-layer metal material, so that the metal composite board has high comprehensive mechanical properties.

The main production methods of the metal composite plate at present comprise an explosive composite plate, a diffusion cladding method, a brazing method and a rolling cladding method, wherein the rolling cladding method is widely used. The rolling and compounding method includes treating the surface of metal to be compounded properly to reach the aim of cleaning and activating, assembling, welding peripheral seam to prevent interface oxidation during heating, heating the welded blank to certain temperature, rolling and deforming under great rolling amount to realize compounding of dissimilar metals under the action of heat and force.

Due to the relationship of experimental equipment, when most colleges and manufacturers roll metal composite plates, peripheral gaps are usually directly welded, and then metallurgical bonding is realized under the strong pressure of a rolling mill. Regarding the welding process, most researchers will open holes directly at the composite part of the composite plate or weld the steel pipe after opening the holes and vacuumize, for example, the chinese patent application No. is: 201510247496.7, publication date is: patent document 2015 9/month and 2 discloses a rolling method of a titanium steel composite plate, which comprises the following steps: a. preparing two steel plates, two titanium plates and four side plates, and removing surface oxide layers and oil stains; b. forming a hole in at least one of the side plates, and welding a seamless carbon steel pipe at the hole; c. symmetrically assembling steel plates/titanium plates/steel plates in sequence, and welding to form a combined body; d. after welding, the welding head is connected with a vacuum pump through a seamless carbon steel pipe, and the welding head is vacuumized until the pressure intensity is not more than 1 multiplied by 10^- ²And Pa, sealing the seamless carbon steel pipe to obtain a combined blank.

For another example, the chinese patent application No. is: 201210260229.X, published as: the patent document of 2012, 11/14 discloses a method for preparing a titanium-steel single-sided composite board, which comprises the following steps: (1) respectively selecting two titanium plates with the same size and two steel plates with the same size, and carrying out rust removal and oxide layer removal treatment on the surfaces of the titanium plates and the steel plates; (2) assembling to form a steel plate-transition layer-titanium plate-separant-titanium plate-transition layer-steel plate symmetrical multi-layer combined blank, wherein gaps are reserved between the periphery of the titanium plate and the barrier strips in the combined blank; (3) pressing the combined blank and respectively welding the barrier strips with the first steel plate and the second steel plate to form a closed cavity inside the first steel plate, the second steel plate and the barrier strips, drilling holes on the barrier strips and welding steel pipes in the holes to communicate the steel pipes with the closed cavity; (4) sending the combined blank into a heating furnace for heating and vacuumizing; (5) sealing the outer end of the steel pipe, and then feeding the combined blank into a rolling mill for rolling; (6) and (4) cutting after rolling to obtain the titanium-steel single-sided composite board.

However, although the air at the interface is conveniently discharged in the heating and rolling processes due to the direct opening of the holes, the interface bonding rate is prevented from being reduced due to the expansion of the interface air caused by heating, and the bonding quality of the composite plate is influenced by the oxidation of part of the composite plate interface bonding positions around the small holes due to the heating and rolling effects, so that the bonding strength of the composite plate is reduced; the method of welding steel pipes after the holes are opened and vacuumizing can reduce the content of oxygen in a composite interface, so that the composite plate with high bonding strength is obtained. However, in many colleges and universities, equipment for vacuumizing is not specially used, because vacuumizing equipment is expensive, the equipment is not widely applied to the colleges and is owned by only some research institutes, factories and the like; in addition, the vacuumizing process is complex, the welding quality is required to be high, any cracking place cannot be provided, the plate cannot be too large, otherwise, the vacuumizing effect cannot be achieved, and the running period is long.

Disclosure of Invention

1. Problems to be solved

Aiming at the existing technology for rolling metal composite plates, when blanks are welded, holes are directly formed in the composite joint of the composite plates, and the interface joint is easily oxidized, so that the quality of the composite plate is influenced, and the bonding strength of the composite plate is reduced; the invention provides a method for preventing the interface oxidation of a rolled metal composite plate, and the method solves the problems that the equipment for vacuumizing a welded steel pipe after tapping is expensive and the process is complex.

2. Technical scheme

In order to solve the problems, the technical scheme adopted by the invention is as follows:

a method for preventing the interface of a rolled metal composite plate from being oxidized comprises the following steps: before heating and rolling, an air vent is opened at the interface recombination position, and then the air vent is blocked by a sealing plug. The metal includes stainless steel and aluminum alloy, but not limited to the above, preferably stainless steel.

Preferably, the exhaust hole is a round hole with the diameter of 8-12 mm, and the depth of the hole is 5-10 mm.

Preferably, the sealing plug is in a circular truncated cone shape, the diameter of the end face of the small end of the sealing plug is 6-10 mm, the diameter of the end face of the large end of the sealing plug is 12-15 mm, and the height of the sealing plug is 8-12 mm.

Preferably, the diameter of the vent hole is 10mm, and the opening depth is 8 mm; the diameter of the small end face of the sealing plug is 8mm, the diameter of the large end face of the sealing plug is 15mm, and the height of the sealing plug is 10 mm.

Preferably, the vent holes are located at the end of the rolling direction.

Preferably, the number of the exhaust holes is 1, the number of the open holes is not too large, and the open holes may allow outside air to enter the composite interface, thereby affecting the composite quality.

Preferably, the melting point of the sealing plug is greater than the melting point of the stainless steel clad plate blank.

A method of rolling a metal composite plate comprising the steps of:

(1) preparing raw materials: cutting a blank with a required specification;

(2) surface treatment: cleaning and activating the surface of the metal to be compounded;

(3) assembling and welding: oppositely overlapping the processed blanks together, and welding peripheral gaps;

(4) opening a hole: opening an exhaust hole at the interface composite position, and then plugging the exhaust hole by using a sealing plug;

(5) heating: putting the blank into a heating furnace for heating, and then preserving heat;

(6) rolling: and feeding the heated blank into a rolling mill for rolling.

Preferably, in the step (1), a blank with a required specification is cut from a large-size plate by wire cutting; in the step (2), firstly, the surface of the composite metal to be treated is polished by abrasive paper, and then, the composite metal is scrubbed by acetone and alcohol to play an activating role; in the step (3), firstly, the composite board is fixed in a spot welding mode, and then the periphery of the composite board is welded by a welding machine; in the step (4), firstly, a drill bit is used for drilling a hole with the diameter of 10mm at the composite position of the composite plate, then the sealing plug is plugged, and the composite plate is welded by means of spot welding.

A method of rolling a stainless steel composite panel comprising the steps of:

(1) preparing raw materials: cutting 316L stainless steel plates and Q345R carbon steel plate blanks with required specifications from large-size plates by wire cutting;

(2) surface treatment: polishing the surface of the steel plate blank by using abrasive paper, and then scrubbing by using acetone and alcohol;

(3) assembling and welding: oppositely stacking the processed blanks together, and welding peripheral gaps to form a welding layer;

(4) opening a hole: opening an exhaust hole at the interface recombination position, and then plugging the exhaust hole by using a sealing plug (such as a titanium plate plug);

(5) heating: putting the blank into a heating furnace, heating to 1000-1250 ℃, and preserving heat for 30 min;

(6) rolling: and (3) feeding the heated blank into a rolling mill for rolling, wherein the rolling speed is 100mm/s, and the total rolling reduction rate is 81.33%.

According to the invention, a welded blank is provided with an exhaust hole at the composite interface position by using a drill bit, then is blocked by using a sealing plug, and is then spot-welded at the exhaust hole, the inside of the sealing plug is small, the outside of the sealing plug is large, and outside air is not easy to enter the composite interface position of the composite plate; in the heating and rolling process of the composite plate, because the air in the composite plate expands due to heating, the air pressure at the interface is higher than the external pressure, and the composite plate is extruded by materials in the rolling process, the air at the composite interface is easy to discharge out of the body, so that the oxidation degree at the composite interface is reduced, and the effect of improving the composite quality is achieved.

3. Advantageous effects

Compared with the prior art, the invention has the beneficial effects that:

(1) the method for preventing the interface oxidation of the rolled metal composite plate can not only reduce the interface oxidation of the metal composite plate in the heating and rolling processes, but also avoid the problem that the interface bonding strength of the composite plate is reduced because the air between the composite interfaces is heated and expanded in the heating and rolling processes of the composite plate, so that the interface bonding rate of the composite plate is reduced;

(2) the method for preventing the interface of the rolled metal composite plate from being oxidized has the advantages of orderly connected steps and easy operation.

Drawings

Fig. 1 is a schematic structural view of a metal composite plate in example 1 of the present invention;

FIG. 2 is a perspective view of a titanium plate plug of the present invention;

FIG. 3 is a left side view of a titanium plate plug of the present invention;

FIG. 4 is a cross-sectional view taken along line A-A of FIG. 3;

fig. 5 is a right side view of a titanium plate plug of the present invention.

In the figure: 1. a 316L stainless steel plate; 2. welding the layers; 3. titanium plate plugs; 31. an air inlet; 32. an air outlet; 33. an air tank; 34. a baffle plate; 35. a telescoping member; 4. Q345R carbon steel plate.

Detailed Description

The invention is further described with reference to specific examples.

Example 1

A method of rolling a stainless steel composite panel comprising the steps of:

(1) preparing raw materials: blanks of 316L stainless steel plate 1 and Q345R carbon steel plate 2 of appropriate size were cut out from large size steel plates by wire cutting. The cut 316L stainless steel 1 had a dimension of 200mm × 100mm × 5mm, and the carbon steel Q345R had a 4-dimension of 200mm × 100mm × 25 mm.

(2) Surface treatment: the surface of the composite blank needs to be treated before assembly welding, so that the bonding rate of the composite surface is increased. Firstly, polishing the surface by using sand paper to remove a rust layer and an oxide layer on the surface; and then repeatedly scrubbing the composite surface by using acetone and alcohol to remove organic matters and dirt on the surface, and quickly drying by using a blower.

(3) Assembling and welding: in order to enable the composite board to have good welding quality, the periphery of the composite board is required to be polished clean by abrasive paper, and repeatedly scrubbed by acetone and alcohol to remove an oxide layer on the periphery of the composite board; then, relatively overlapping the processed blanks together, and fixing the composite plate by spot welding to avoid the welding quality from being influenced by dislocation in the welding process; and then welding the periphery of the stainless steel composite plate by using a welding machine to form a welding layer 2. In order to enable the composite board to have better interface bonding strength, the argon arc welding mode is adopted for welding.

(4) Opening a hole: and (3) forming an exhaust hole in the interface composite position of the welded blank by using a drill, wherein the exhaust hole is a circular hole with the diameter of 10mm, the opening depth is 8mm, and then spot-welding the titanium plate plug 3 at the exhaust hole. Titanium plate stopper 3 is the round platform form, and its tip diameter is 8mm, and the main aspects diameter is 12mm, highly is 10mm, adopts big structure outside little in, consequently, the air between the composite sheet interface is easily discharged, and external air is difficult for getting into, so can avoid the composite sheet interface to be by the oxidation once more at heating and rolling in-process, and because the gaseous discharge in composite interface, reduced the composite sheet and leaded to the composite sheet to separate because of the air thermal expansion, so can improve composite sheet interface bonding strength.

(5) Heating: and (3) placing the welded blank into a heating furnace to be heated to 1200 ℃, and preserving heat for 30 min.

(6) Rolling: the heated stainless steel composite plate was sent to a rolling mill for rolling at a rolling speed of 100mm/s and a total reduction of 81.33%, and the vent holes were located at the ends in the rolling direction. And air-cooling to room temperature after rolling to obtain the stainless steel composite board.

Research shows that the vacuum atmosphere of the composite billet cavity plays at least the following three roles on the technological effect of hot rolling composite: an oxygen-free environment is formed, and the oxidation of the surface of the metal is prevented from forming an oxide film which influences the compounding; preventing the formation of bubbles at the recombination interface; preventing the gas molecules from forming microscopic non-metal inclusions which influence the shearing strength on the metal composite surface.

From production practice, it is found that the higher the vacuum degree in the composite blank cavity, the higher the recombination rate and the recombination strength. The vacuum degree (absolute pressure) required by hot rolling compounding is (1-20) x 10^－3Pa. If the welding process adopts the mode of vacuumizing the welded steel pipe after the hole is opened, the vacuum degree in the composite blank is ensured not to be higher than 10 during steel rolling^－3Pa, considering the factors of gas pressure rising along with temperature and gas separation in the metal, and forming a vacuum degree higher by one order of magnitude in the composite blank in the vacuum pumping link. But it is very difficult to form a vacuum level that is an order of magnitude higher.

Comparative example 1

The method for rolling the stainless steel composite plate according to the comparative example 1 basically has the same steps as the example 1, except that the titanium plate plug 3 is not used for blocking after the vent hole is opened in the step (4).

Comparative example 2

The method for rolling the stainless steel composite plate according to the comparative example 1 basically comprises the same steps as the example 1, except that after the exhaust hole is formed in the step (4), a steel pipe is welded in the exhaust hole to enable the steel pipe to be communicated with the blank cavity, and then the blank cavity is vacuumized to enable the vacuum degree to reach 0.02 Pa.

The 316L/Q345R composite plates obtained in example 1, comparative example 1 and comparative example 2 were tested for the composite rate according to "JB/T4730.3-2005" pressure equipment nondestructive test "standard, and the composite steel plate substrate and composite material joint surface parallel to the test force direction were sheared by a shearing device until they were separated, to determine the shear strength, i.e., the composite strength data, and the data obtained are shown in Table 1 below:

table 1 composite rate and composite strength data of composite boards in example 1, comparative example 1 and comparative example 2

As can be seen from comparison of Table 1, the stainless steel composite plate prepared in example 1 has a straight composite interface, almost no non-composite surface, shear strength far higher than 210MPa required in national standard, and performance obviously superior to that of the composite plate obtained in comparative example 1, basically achieves the composite effect of the composite plate obtained in comparative example 1, and can meet the field use requirement of a factory on the premise of lacking vacuum pumping equipment. In addition, in the bending test, no obvious cracking phenomenon is found in the stainless steel composite plate prepared in the example 1 whether the stainless steel composite plate is bent outwards or inwards.

Example 2

A method of rolling a stainless steel composite panel comprising the steps of:

(1) preparing raw materials: blanks of 316L stainless steel plate 1 and Q345R carbon steel plate 4 of the desired gauge of the appropriate size were cut from the large size steel plate by wire cutting. The cut 316L stainless steel 1 had a dimension of 200mm × 100mm × 5mm, and the Q345R carbon steel 4 had a dimension of 200mm × 100mm × 25 mm.

(2) Surface treatment: firstly, polishing the surface by using sand paper to remove a rust layer and an oxide layer on the surface; and then repeatedly scrubbing the composite surface by using acetone and alcohol to remove organic matters and dirt on the surface, and quickly drying by using a blower.

(3) Assembling and welding: polishing the periphery of the composite board by using sand paper, and repeatedly scrubbing by using acetone and alcohol to remove an oxide layer on the periphery of the composite board; and then, relatively overlapping the processed blanks together, fixing the composite plate by spot welding, and welding the periphery of the stainless steel composite plate by a welding machine to form a welding layer 2.

(4) Opening a hole: and (3) forming an exhaust hole in the interface composite position of the welded blank by using a drill, wherein the exhaust hole is a circular hole with the diameter of 8mm, the opening depth is 5mm, and then spot-welding the titanium plate plug 3 at the exhaust hole. The titanium plate plug 3 is in a circular truncated cone shape, the diameter of the small end of the titanium plate plug is 6mm, the diameter of the large end of the titanium plate plug is 12mm, and the height of the titanium plate plug is 8 mm.

(5) Heating: and (3) placing the welded blank into a heating furnace, heating to 1000 ℃, and preserving heat for 30 min.

The stainless steel composite plate prepared by the method has a straight composite interface, basically has no non-composite surface, has the shear strength of 350MPa, and has no obvious cracking phenomenon no matter whether the stainless steel composite plate is bent outwards or inwards in a bending experiment.

Example 3

A method of rolling a stainless steel composite panel comprising the steps of:

(1) preparing raw materials: blanks of 316L stainless steel plate 1 and Q345R carbon steel plate 4 of appropriate size were cut out from large size steel plates by wire cutting. The cut 316L stainless steel 1 had a dimension of 200mm × 100mm × 5mm, and the Q345R carbon steel 4 had a dimension of 200mm × 100mm × 25 mm.

(4) Opening a hole: and (3) forming an exhaust hole in the interface composite position of the welded blank by using a drill, wherein the exhaust hole is a circular hole with the diameter of 12mm, the opening depth is 12mm, and then spot-welding the titanium plate plug 3 at the exhaust hole. The titanium plate plug 3 is in a circular truncated cone shape, the diameter of the small end of the titanium plate plug is 10mm, the diameter of the large end of the titanium plate plug is 15mm, and the height of the titanium plate plug is 12 mm.

(5) Heating: and (3) putting the welded blank into a heating furnace, heating to 1250 ℃, and preserving heat for 30 min.

The stainless steel composite plate prepared by the method has a straight composite interface, basically has no non-composite surface, has the shear strength of 320MPa, and has no obvious cracking phenomenon no matter whether the stainless steel composite plate is bent outwards or inwards in a bending experiment.

Example 4

The method for rolling a stainless steel composite plate in this embodiment has the same steps as those in embodiment 3, except that, as shown in fig. 2 to 5, a cavity is formed inside the titanium plate plug 3 used in step (4); the cavity consists of an air inlet hole 31, an air outlet hole 32 and an air groove 33; the air inlet holes 31 are arranged at the small end of the titanium plate plug 3 and are in a gradually expanding type, the air outlet holes 32 are arranged at the large end of the titanium plate plug 3, and the air grooves 33 are communicated with the air inlet holes 31 and the air outlet holes 32. In addition, a baffle 34 is arranged in the air outlet 32, the baffle 34 is used for sealing the air outlet 32, and the baffle 34 is connected with the telescopic piece 35 and can slide along the air outlet 32.

The hollow cavity is arranged inside the titanium plate plug 3, so that more channels are provided for the outflow of air at the composite position of the composite plate interface, and the air at the composite plate interface is favorably discharged outwards under the extrusion action of a rolling mill when being heated and expanded. Particularly, the tip of titanium plate stopper 3 sets up a plurality of inlet ports 31, and the venthole 32 with external UNICOM only has one, and venthole 32 adopts baffle 34 sealed, makes the air can follow inlet port 31, through air duct 33, then pushes away baffle 34 and flows out from venthole 32, but outside air can't get into titanium plate stopper 3 inside from venthole 32, makes titanium plate stopper 3 can assist the gaseous outflow in the time, can play original sealed effect again.

Claims

1. A method for preventing the interface oxidation of a rolled metal composite plate is characterized in that: before heating and rolling, an exhaust hole is formed in the interface composite position, and then the exhaust hole is blocked by a sealing plug, wherein the sealing plug is a titanium plate plug (3), and a cavity is formed in the titanium plate plug (3); the cavity consists of an air inlet hole (31), an air outlet hole (32) and an air groove (33); the air inlet holes (31) are arranged at the small end of the titanium plate plug (3) and are in a gradually expanding mode, the air outlet holes (32) are arranged at the large end of the titanium plate plug (3), and the air groove (33) is communicated with the air inlet holes (31) and the air outlet holes (32).

2. A method of preventing interfacial oxidation in a rolled metal composite sheet according to claim 1, wherein: the exhaust hole is a round hole with the diameter of 8-12 mm, and the opening depth is 5-10 mm.

3. A method of preventing interfacial oxidation in a rolled metal composite sheet according to claim 2, wherein: the sealing plug is in a round table shape, the diameter of the small end face of the sealing plug is 6-10 mm, the diameter of the large end face of the sealing plug is 12-15 mm, and the height of the sealing plug is 8-12 mm.

4. A method of preventing interfacial oxidation in a rolled metal composite sheet according to claim 3, wherein: the diameter of the exhaust hole is 10mm, and the depth of the opening is 8 mm; the diameter of the small end face of the sealing plug is 8mm, the diameter of the large end face of the sealing plug is 15mm, and the height of the sealing plug is 10 mm.

5. The method of claim 4, wherein the step of preventing interfacial oxidation of the rolled metal composite plate comprises: the vent holes are located at the end of the rolling direction.

6. The method of claim 5, wherein the step of preventing interfacial oxidation of the rolled metal composite plate comprises: the number of the exhaust holes is 1.

7. The method of claim 6, wherein the step of preventing interfacial oxidation of the rolled metal composite plate comprises: the melting point of the sealing plug is larger than that of the stainless steel composite board blank.