Patent ID: 12214440

DETAILED DESCRIPTION OF THE EMBODIMENTS

Various exemplary embodiments of the present disclosure are now described in detail, which detailed description should not be considered as a limitation of the present disclosure, but should be understood as a more detailed description of certain aspects, features and embodiments of the present disclosure.

It should be understood that the terminology described in the present disclosure is only for describing specific embodiments and is not used to limit the present disclosure. In addition, for the numerical range in the present invention, it should be understood that each intermediate value between the upper limit and the lower limit of the range is also specifically disclosed. The intermediate value within any stated value or stated range and every smaller range between any other stated value or intermediate value within the stated range are also included in the present disclosure. The upper and lower limits of these smaller ranges are independently included or excluded from the range.

Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure relates. Although the present disclosure only describes the preferred methods and materials, any methods and materials similar or equivalent to those described herein can also be used in the practice or testing of the present disclosure. All documents mentioned in this specification are incorporated by reference to disclose and describe methods and/or materials related to the documents. In case of conflict with any incorporated document, the contents of this specification shall prevail.

It is obvious to those skilled in the art that many improvements and changes are available to the specific embodiments of the present disclosure without departing from the scope or spirit of the present disclosure. Other embodiments will be apparent to the skilled person from the description of the disclosure. The description and embodiments of the present disclosure are exemplary only.

The terms “including”, “comprising”, “having” and “containing” used in this specification are all open terms, which means including but not limited to.

The schematic diagram of composite process of gradient heterothermal rolling of magnesium/titanium composite plate with large thickness ratios of the present disclosure is shown inFIG.1.

In the embodiments of the present disclosure, the magnesium/titanium composite plate with large thickness ratios is prepared by the gradient heterothermal rolling bonding device as shown inFIG.2andFIG.3; a temperature control system in the device includes an induction heating coil, an infrared temperature sensor, a controller and an intermediate frequency induction heating power supply; the control system includes comparing a temperature set value with a measured value of an infrared thermometer, and takes a deviation value of the temperature set value and the measured value as an input of the controller, the controller calculates the deviation value of the two, then outputs a corresponding control voltage signal to the induction heating power supply, and the induction heating power supply outputs a power corresponding to a control signal to carry out heating; a platform of a lifting mechanism in the device is used to fix the electromagnetic induction heating coil, and the up and down positions of the plate blank induction heating device are shifted by an externally connected lifting device, so that the electromagnetic induction coil is parallel to the plate blank and the distance is controllable. Other rolling devices that are capable of realizing temperature control of gradient heating may also be used to realize the preparation of magnesium/titanium composite plate with large thickness ratios.

The finite element simulation and verification at the surface interface of the gradient temperature field of the disclosure is shown inFIG.4A-FIG.4C.

Embodiment 1

Step 1, pretreatment of plate blank: titanium strip TC4, aluminum foil AA1100 and magnesium alloy plate with large thickness AZ31 with thicknesses of 0.1 mm, 0.05 mm and 8 mm respectively are selected and prepared into standard rectangular blocks (with the same size of 80 millimeters (mm)×50 mm in length and width), followed by processing and chamfering; the titanium strip is placed in a box-type vacuum heat-treating furnace at 900 degrees Celsius (° C.) and held for 60 minutes (min), the magnesium alloy plate with large thickness is placed in a box-type vacuum heat-treating furnace at 300° C. and held for 30 min, the aluminum foil is placed in a box-type vacuum heat-treating furnace at 350° C. and held for 10 min, followed by furnace cooling and annealing treatment respectively, where the annealing atmosphere is argon, the pressure of the argon is 0.95 megapascal (MPa) (technical effects of 0.95-1 MPa and 0.95 MPa are fairly comparable), and the quality purity of argon is 99.99%;the surfaces of magnesium alloy plate with large thickness, titanium strip and aluminium foil are processed, in which magnesium alloy plate as the base layer should be cleaned up at least one side to be combined, titanium plate as the compound layer should also be cleaned up at least one side to be combined with the plate surface, and aluminium foil as the transition layer should be cleaned up the oxide layers of the plate surfaces on both sides, and the contact surfaces to be combined should be appropriately polished along the direction of rolling using rotating steel wire method so as to make the combined surfaces having a certain roughness, and the surface roughness is Average roughness (Ra)1.6 (the technical effect of Ra1.6 may be achieved in a range of Ra0.8-Ra1.6), so as to ensure that the combined area is large enough; after polishing, the contact surfaces to be combined are placed into the acetone solution for ultrasonic cleaning for 10 min (or cleaning with anhydrous ethanol), and then dried with a blower;the cleaned titanium strip, aluminium foil and magnesium alloy plate of large thickness are stacked in order, the surfaces of the surface-treated magnesium alloy plate and the titanium plate are laminated on both sides of the aluminium foil as the surfaces to be combined, and then leveled after the combination is completed to make a composite blank;

Step 2, local induction heating:a. the customized induction heating coil is placed on the titanium strip side of the composite blank to ensure that the induction coil is parallel to the blank, the distance between the coil and the composite blank is adjusted to 5 mm by controlling the lifting device, the frequency of the intermediate-frequency induction power supply is set to 1000 hertz (Hz) and the current density is set to 50 e5amperes per square meter (A/m2), and the required heating temperature of 450° C. is inputted into the controller of the induction heating system;b. after the setup is completed, the intermediate-frequency induction power supply is activated, and the induction coil is charged with alternating current to heat the composite blank for 45 s, so that the composite blank is heated up and warmed up, and after the heating is completed, the composite blank is pushed into the rolling mill with the push plate to be rolled;

Step 3: rolling and compounding: the magnesium/titanium composite plate with large thickness ratios is rolled at a different temperature, the rolling direction and grinding direction should be consistent, the rolling speed is 1.0 meter per second (m/s), the amount of rolling reduction is 20%, the rolled composite blank is placed in a box-type vacuum heat-treating furnace at 500° C. and held for 60 min, followed by furnace cooling, and the protective atmosphere is argon atmosphere with argon gas pressure of 1 MPa, and argon gas quality purity of 99.99%;

Step 4: post-treatment of plate blank: the composite blank after cooling is refined, leveled and cut, and then the surface treatment of the composite plate is carried out by mechanical methods, and the surface is polished to the roughness of Ra1.6, then it is placed in acetone solution and ultrasonically cleaned for 10 min, followed by taken out and drying to obtain the magnesium/titanium composite plate with large thickness ratios without cracks on the surface, as shown inFIG.5. The magnesium/titanium composite plate with large thickness ratios is observed in terms of by binding interface as shown inFIG.6, where the three layers of materials from top to bottom are magnesium alloy, aluminium strip and titanium strip, and it is found that the interface of the composite plate is well combined without defects such as cracks and porosity, and certain plastic deformation occurs in the aluminium strip, with a relatively small thinning of the thickness of the titanium alloy strip.

Embodiment 2

Step 1, pretreatment of plate blank: titanium strip TC6, aluminum foil AA6061 and magnesium alloy plate with large thickness AZ31 with thicknesses of 0.2 mm, 0.05 mm and 10 mm respectively are selected and prepared into standard rectangular blocks (with the same size of 70 mm×40 mm in length and width), followed by processing and chamfering; the titanium strip is placed in a box-type vacuum heat-treating furnace at 950° C. and held for 90 min, the magnesium alloy plate with large thickness is placed in a box-type vacuum heat-treating furnace at 350° C. and held for 40 min, the aluminum foil is placed in a box-type vacuum heat-treating furnace at 400° C. and held for 5 min, followed by furnace cooling and annealing treatment respectively, where the annealing atmosphere is argon, the pressure of the argon is 0.95 MPa (technical effects of 0.95-1 MPa and 0.95 MPa are fairly comparable), and the quality purity of argon is 99.99%;the surfaces of magnesium alloy plate with large thickness, titanium strip and aluminium foil are processed, in which magnesium alloy plate as the base layer should be cleaned up at least one side to be combined, titanium plate as the compound layer should also be cleaned up at least one side to be combined with the plate surface, and aluminium foil as the transition layer should be cleaned up the oxide layers of the plate surfaces on both sides, and the contact surfaces to be combined should be appropriately polished along the direction of rolling using rotating steel wire method so as to make the combined surfaces having a certain roughness, and the surface roughness is Ra1.6 (the technical effect of Ra1.6 can be achieved in a range of Ra0.8-Ra1.6), so as to ensure that the combined area is large enough, after polishing, the contact surfaces to be combined are placed into the acetone solution for ultrasonic cleaning for 10 min (or cleaning with anhydrous ethanol), and then dried with a blower;the cleaned titanium strip, aluminium foil and magnesium alloy plate of large thickness are stacked in order, the surfaces of the surface-treated magnesium alloy plate and the titanium plate are laminated on both sides of the aluminium foil as the surfaces to be combined, and then leveled after the combination is completed to make a composite blank;

Step 2, local induction heating:a. the customized induction heating coil is placed on the titanium strip side of the composite blank to ensure that the induction coil is parallel to the blank, the distance between the coil and the composite blank is adjusted to 4 mm by controlling the lifting device, the frequency of the intermediate-frequency induction power supply is set to 1500 Hz and the current density is set to 40 e5A/m2, and the required heating temperature of 400° C. is inputted into the controller of the induction heating system;b. after the setup is completed, the intermediate-frequency induction power supply is activated, and the induction coil is charged with alternating current to heat the composite blank for 50 s, so that the composite blank is heated up and warmed up, and after the heating is completed, the composite blank is pushed into the rolling mill with the push plate to be rolled;

Step 3: rolling and compounding: the magnesium/titanium composite plate with large thickness ratios is rolled at a different temperature, the rolling direction and grinding direction should be consistent, the rolling speed is 1.0 m/s, the amount of rolling reduction is 15%, the rolled composite blank is placed in a box-type vacuum heat-treating furnace at 450° C. and held for 60 min, followed by furnace cooling, and the protective atmosphere is argon atmosphere with argon gas pressure of 1 MPa, and argon gas quality purity of 99.99%;

Step 4: post-treatment of plate blank: the composite blank after cooling is refined, leveled and cut, and then the surface treatment of the composite plate is carried out by mechanical methods, and the surface is polished to the roughness of Ra1.6, then it is placed in acetone solution and ultrasonically cleaned for 10 min, followed by taken out and drying to obtain the magnesium/titanium composite plate with large thickness ratios without cracks on the surface; the interface of the composite plate is well combined without defects such as cracks and porosity, and certain plastic deformation occurs in the aluminium strip, with a relatively small thinning of the thickness of the titanium alloy strip.

Embodiment 3

Step 1, pretreatment of plate blank: titanium strip TC10, aluminum foil AA1100 and magnesium alloy plate with large thickness AZ61 with thicknesses of 0.4 mm, 0.05 mm and 15 mm respectively are selected and prepared into standard rectangular blocks (with the same size of 80 mm×40 mm in length and width), followed by processing and chamfering; the titanium strip is placed in a box-type vacuum heat-treating furnace at 1000° C. and held for 90 min, the magnesium alloy plate with large thickness is placed in a box-type vacuum heat-treating furnace at 300° C. and held for 45 min, the aluminum foil is placed in a box-type vacuum heat-treating furnace at 300° C. and held for 15 min, followed by furnace cooling and annealing treatment respectively, where the annealing atmosphere is argon, the pressure of the argon is 0.95 MPa (technical effects of 0.95-1 MPa and 0.95 MPa are fairly comparable), and the quality purity of argon is 99.99%;the surfaces of magnesium alloy plate with large thickness, titanium strip and aluminium foil are processed, in which magnesium alloy plate as the base layer should be cleaned up at least one side to be combined, titanium plate as the compound layer should also be cleaned up at least one side to be combined with the plate surface, and aluminium foil as the transition layer should be cleaned up the oxide layers of the plate surfaces on both sides, and the contact surfaces to be combined should be appropriately polished along the direction of rolling using rotating steel wire method so as to make the combined surfaces having a certain roughness, and the surface roughness is Ra1.6 (the technical effect of Ra1.6 can be achieved in a range of Ra0.8-Ra1.6), so as to ensure that the combined area is large enough, after polishing, the contact surfaces to be combined are placed into the acetone solution for ultrasonic cleaning for 10 min (or cleaning with anhydrous ethanol), and then dried with a blower;the cleaned titanium strip, aluminium foil and magnesium alloy plate of large thickness are stacked in order, the surfaces of the surface-treated magnesium alloy plate and the titanium plate are laminated on both sides of the aluminium foil as the surfaces to be combined, and then leveled after the combination is completed to make a composite blank;

Step 2, local induction heating:a. the customized induction heating coil is placed on the titanium strip side of the composite blank to ensure that the induction coil is parallel to the blank, the distance between the coil and the composite blank is adjusted to 5 mm by controlling the lifting device, the frequency of the intermediate-frequency induction power supply is set to 3000 Hz and the current density is set to 40 e5A/m2, and the required heating temperature of 500° C. is inputted into the controller of the induction heating system;b. after the setup is completed, the intermediate-frequency induction power supply is activated, and the induction coil is charged with alternating current to heat the composite blank for 45 s, so that the composite blank is heated up and warmed up, and after the heating is completed, the composite blank is pushed into the rolling mill with the push plate to be rolled;

Step 3: rolling and compounding: the magnesium/titanium composite plate with large thickness ratios is rolled at a different temperature, the rolling direction and grinding direction should be consistent, the rolling speed is 0.5 m/s, the amount of rolling reduction is 15%, the rolled composite blank is placed in a box-type vacuum heat-treating furnace at 500° C. and held for 90 min, followed by furnace cooling, and the protective atmosphere is argon atmosphere with argon gas pressure of 1 MPa, and argon gas quality purity of 99.99%;

Step 4: post-treatment of plate blank: the composite blank after cooling is refined, leveled and cut, and then the surface treatment of the composite plate is carried out by mechanical methods, and the surface is polished to the roughness of Ra1.6, then it is placed in acetone solution and ultrasonically cleaned for 10 min, followed by taken out and drying to obtain the magnesium/titanium composite plate with large thickness ratios without cracks on the surface; the interface of the composite plate is well combined without defects such as cracks and porosity, and certain plastic deformation occurs in the aluminium strip, with a relatively small thinning of the thickness of the titanium alloy strip.

The gradient heterothermal rolling bonding method provided by the present disclosure promotes the high-quality combination of heterogeneous materials under small rolling reduction, thus lowering the critical composite deformation rate and greatly reducing the performance requirements for the rolling mill. The surface quality of the composite plate obtained is good, with no cracking at the edges and ends, flat plate shape, good bonding interface, uniform and fine plate organization, and excellent mechanical properties.

The above-mentioned embodiments only describe the preferred mode of the present disclosure, and do not limit the scope of the present disclosure. Under the premise of not departing from the design spirit of the present disclosure, various modifications and improvements made by ordinary technicians in the field to the technical scheme of the present disclosure shall fall within the protection scope determined by the claims of the present disclosure.