Copper clad aluminum alloy non-annealing rolling method

Abstract

The present application relates to high-quality aluminum alloy plate processing technology field, disclose a kind of copper clad aluminum alloy annealing-free rolling method, comprising: removing composite blank surface dirt and oxide skin and completing straightening, send into cantilever rolling mill;Control 9 pass continuous cold rolling, so that single pass reduction rate is in the range of 8% to 15%, the rolling speed of the first 8 passes is gradually increased from 0.4m / s to 1.0m / s, and the single pass reduction rate is distributed in gradient decreasing;Finished pass rolling speed is stabilized at 1.2m / s, combined with preset pressure interval spraying emulsion, the present application offsets heterogeneous metal interface shear stress accumulation by discretization distribution total deformation, balances oil film thickness and exports interface heat using dynamic pressure lubrication mechanism generated by high-speed rolling, realizes copper layer and aluminum matrix synchronous plastic extension under the condition of no intermediate annealing, ensures finished product size precision and surface quality.

Description

Technical Field

[0001] This invention relates to a method for non-annealing rolling of copper-clad aluminum alloy, belonging to the field of high-quality aluminum alloy sheet processing technology. Background Technology

[0002] Currently, copper-clad aluminum alloy composite flats are used in power transmission and transportation equipment manufacturing due to their high conductivity and low density. Their manufacturing process usually involves a multi-pass cold rolling process with large deformation. In order to coordinate the difference in yield stress between copper and aluminum phases during rolling deformation, the current mainstream solution usually adopts an intermediate annealing process to restore the plasticity of the material and release the interfacial strain energy. Although this path, which relies on periodic heat treatment, can maintain the stability of the cladding bond, it increases production energy consumption and turnaround time, and is prone to generating brittle oxides at the two-phase interface, reducing the overall bonding performance of the profile.

[0003] Industry experts have attempted to implement anneal-free rolling by reducing single-pass reduction or optimizing lubrication parameters. However, under continuous large deformation conditions, the lack of dynamic feedback and compensation mechanisms for the microscopic slip state at the interface makes this linear improvement approach prone to cladding cracking or surface damage. This technical constraint caused by the deformation mismatch of dissimilar metals reflects the contradiction between mechanical control parameters and the physical evolution of the interface under large deformation conditions. At the hardware level, stability can be improved by modifying the roll body curve or optimizing guide limits. However, within the context of roll design and guide hardware optimization, dynamic control logic and lubrication compensation mechanisms remain constraints on high quality. Factors affecting the continuous production of composite materials include, for example, a Chinese invention patent with authorization announcement number CN109201739B that discloses a method for preparing high-performance ultrafine-grained copper / aluminum / copper composite strip. Although interface welding is achieved through hot rolling and deep cold rolling, under high-speed continuous large deformation cold rolling conditions, the static parameter configuration is difficult to cope with the nonlinear accumulation of interface shear stress caused by rolling rate fluctuations. The idealized static step sequence control logic, when facing production boundaries without annealing and with high strain rate, lacks physical coupling compensation between lubricating medium pressure and dynamic thermal field, leading to instability of the dynamic pressure oil film bearing capacity, causing coating cracking or interface deformation mismatch.

[0004] Therefore, the technical problem to be solved by this invention is how to address the interface slip mismatch problem under large deformation, and simultaneously improve the coating bonding force and profile dimensional accuracy through the synergistic coupling of process parameters, without eliminating the intermediate annealing process, thus proposing a copper-clad aluminum alloy non-annealing rolling method. Summary of the Invention

[0005] To address the problems mentioned in the background art, the technical solution of the present invention is as follows: A method for non-annealing rolling of copper-clad aluminum alloy, comprising the following steps:

[0006] Step 101: The copper-clad aluminum alloy composite billet is subjected to surface degreasing treatment, physical descaling treatment and multi-roll straightening treatment in sequence to control the straightness of the copper-clad aluminum alloy composite billet within 1.5mm / m, and the straightness is used as the physical constraint reference for subsequent guide biting.

[0007] Step 102: The straightened copper-clad aluminum alloy composite billet is fed into the positioning guide device of the cantilever mill, the hydraulic pressing adjustment mechanism of the cantilever mill is adjusted to the preset initial pressing parameters, the circulating emulsion lubrication system is started and emulsion is sprayed onto the deformation zone of the cantilever mill, and the initial oil supply pressure of the emulsion is set in the range of 0.35MPa to 0.40MPa.

[0008] Step 103: The copper-clad aluminum alloy composite billet is subjected to 9 consecutive cold rolling passes using the cantilever mill, with the single-pass reduction rate controlled within the range of 8% to 15% for each pass. During the first 8 passes of cold rolling, the rolling speed is gradually increased from 0.4 m / s to 1.0 m / s using a speed control system, and the single-pass reduction rate for the first 8 passes is distributed in a gradient decreasing from 15% to 8% to offset the accumulation of nonlinear shear stress at the interface between the copper layer and the aluminum matrix by discretizing the total deformation.

[0009] Step 104: The copper-clad aluminum alloy composite billet after the first 8 passes of cold rolling is fed into the finishing pass for the last rolling. The rolling speed of the finishing pass is adjusted to a steady state of 1.2 m / s, and the rolling force feedback signal is monitored in real time to dynamically correct the roll gap of the finishing pass, so that the cross-sectional dimension accuracy of the produced copper-clad aluminum alloy flat steel is controlled within ±0.05 mm.

[0010] Preferably, in step 104, while the rolling speed of the finished pass is maintained at 1.2 m / s, the emulsion lubrication system uses a 45° spray angle to force lubricate the deformation zone. The impact force generated by the emulsion balances the thickness of the dynamic pressure lubricating oil film between the roll of the finished pass and the contact surface of the copper-clad aluminum alloy composite billet, and simultaneously removes the interface friction heat.

[0011] Preferably, the cantilever mill is equipped with rolling bearings and an independent oil supply unit. The oil supply pressure output by the oil supply unit is controlled within the range of 0.15MPa to 0.25MPa to reduce the rotational resistance fluctuation of the roll system of the cantilever mill. The speed feedback signal of the speed controller of the cantilever mill is used to compensate for the transient rolling force impact load generated by the copper-clad aluminum alloy composite billet at the moment of biting.

[0012] Preferably, in step 101, a multi-roll straightener is used to control the straightness of the copper-clad aluminum alloy composite billet in each dimension, so that when the copper-clad aluminum alloy composite billet enters the positioning and guiding device, the consistency deviation between the geometric center line of the copper-clad aluminum alloy composite billet and the rolling center line of the cantilever mill is within a preset tolerance range, thereby avoiding bite-off defects in the first rolling pass.

[0013] Preferably, the emulsion lubrication system further includes a circulating heat exchange device, which is used to maintain the supply temperature of the emulsion at a constant range of 35°C to 45°C. The emulsion lubrication system also adjusts the emulsion ratio in real time to control the mass percentage concentration of the emulsion within the range of 4% to 6% in order to maintain the shear viscosity stability of the hydrodynamic lubricating oil film.

[0014] Preferably, under the hydrodynamic lubrication state in step 104, the surface roughness of the produced copper-clad aluminum alloy flat steel product is maintained below Ra0.8μm through the physical mapping of the surface morphology of the roll, and the overall flatness of the copper-clad aluminum alloy flat steel product is maintained within 0.1mm / m by the post-tension traction of the finished product pass.

[0015] Preferably, in step 104, the oil supply pressure P of the emulsion is linearly compensated in real time for changes in the rolling speed v of the finished product pass. The oil supply pressure P satisfies the following formula: P = k × v + P0, where P is the oil supply pressure of the emulsion, k is the pressure response coefficient with a value ranging from 0.2 to 0.3, and v is the rolling speed of the finished product pass. The preset base oil supply pressure ranges from 0.11 MPa to 0.19 MPa.

[0016] Preferably, after step 104, the copper-clad aluminum alloy flat steel product is subjected to online alkaline washing, water rinsing and hot air drying in sequence. The alkaline washing process removes the residual emulsion film on the surface of the copper-clad aluminum alloy flat steel product, and the hot air drying process prevents water stains or oxide spots from forming on the surface of the copper-clad aluminum alloy flat steel product.

[0017] Preferably, the hydraulic pressing adjustment mechanism includes a high-frequency servo hydraulic cylinder and a displacement sensor. The high-frequency servo hydraulic cylinder performs closed-loop compensation adjustment of the roll gap in each pass of the nine-pass continuous cold rolling according to the piston stroke signal fed back by the displacement sensor, so as to maintain the single-pass pressing accuracy of the copper-clad aluminum alloy composite billet within the preset control dead zone range.

[0018] Preferably, in step 103, the single-pass reduction rate of the first 8 passes is linearly decreasing with equal deviation, and during the first 8 passes of cold rolling, the micro-tension coefficient of the copper-clad aluminum alloy composite billet between each stand is controlled so that the copper layer and the aluminum matrix in the copper-clad aluminum alloy composite billet undergo synchronous plastic elongation deformation without intermediate annealing.

[0019] Compared with the prior art, the beneficial effects of the present invention are:

[0020] 1. In the non-annealing rolling of copper-clad aluminum alloys, a nine-pass continuous cold rolling method with a single-pass deformation distribution of 8% to 15% is adopted to ensure that the copper layer and the aluminum matrix maintain coordinated deformation under the condition of no intermediate annealing. This gradient-decreasing deformation path suppresses the nonlinear accumulation of shear stress at the interface of dissimilar metals. By discretizing the total deformation, the interfacial shear force in each rolling pass is always lower than the yield limit of the material, thereby eliminating the interface peeling and interlayer cracking phenomena commonly found in non-annealing cold rolling processes.

[0021] 2. The steady-state rolling speed of 1.2 m / s for the finished pass and the emulsion oil supply pressure of 0.35 MPa to 0.55 MPa form a dynamic coupling. Within this speed range, the lubricating medium generates a continuous dynamic pressure oil film in the deformation zone where the rolls and the billet contact. The thickness of this oil film is balanced with the scouring force generated by the 45° inclined spray angle. While reducing the coefficient of friction, it quickly dissipates the heat generated by the micro-slip at the interface, keeping the surface roughness of the finished product below Ra0.8 μm. The cantilever mill body, combined with the independent oil supply system of rolling bearings at 0.15 MPa to 0.25 MPa, reduces the transient resistance fluctuations during the operation of the roll system. This low-damping operating state, combined with the dynamic feedback of the speed controller, weakens the impact load on the billet caused by the sudden change in rolling force, keeping the flatness of the finished flat steel within 0.1 mm / m and the dimensional accuracy of the finished product within ±0.05 mm, meeting the geometric tolerance requirements of wide flat steel.

[0022] 3. By working together with the billet positioning and guiding mechanism and the speed control system, a physical trajectory constraint mechanism for 40mm wide incoming materials is constructed. The adjustable limit block and the straightening wheel work together to correct the center line of the billet in real time during the nine-pass continuous rolling process. With the real-time feedback of the finished product online detection mechanism, the system can immediately reorganize the power output through the variable frequency drive motor when it senses the tendency of dimensional deviation, so as to avoid profile warping or excessive edge burrs caused by uneven force on the wide billet. Attached Figure Description

[0023] Figure 1 This is a flowchart of the process steps for the non-annealing continuous cold rolling of copper-clad aluminum alloy according to the present invention.

[0024] Figure 2This is a logic diagram for dynamic compensation of emulsion oil supply pressure based on multi-parameter feedback in this invention.

[0025] The objectives, features, and advantages of this invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0026] The technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this application are within the scope of protection of this application.

[0027] A method for non-annealing rolling of copper-clad aluminum alloy includes the following steps:

[0028] Step 101: The copper-clad aluminum alloy composite billet is subjected to surface degreasing treatment, physical descaling treatment and multi-roll straightening treatment in sequence to control the straightness of the copper-clad aluminum alloy composite billet within 1.5mm / m, and the straightness is used as the physical constraint reference for subsequent guide biting.

[0029] Step 102: The straightened copper-clad aluminum alloy composite billet is fed into the positioning guide device of the cantilever mill, the hydraulic pressing adjustment mechanism of the cantilever mill is adjusted to the preset initial pressing parameters, the circulating emulsion lubrication system is started and emulsion is sprayed onto the deformation zone of the cantilever mill, and the initial oil supply pressure of the emulsion is set in the range of 0.35MPa to 0.40MPa.

[0030] Step 103: The copper-clad aluminum alloy composite billet is subjected to 9 consecutive cold rolling passes using the cantilever mill, with the single-pass reduction rate controlled within the range of 8% to 15% for each pass. During the first 8 passes of cold rolling, the rolling speed is gradually increased from 0.4 m / s to 1.0 m / s using a speed control system, and the single-pass reduction rate for the first 8 passes is distributed in a gradient decreasing from 15% to 8% to offset the accumulation of nonlinear shear stress at the interface between the copper layer and the aluminum matrix by discretizing the total deformation.

[0031] Step 104: The copper-clad aluminum alloy composite billet after the first 8 passes of cold rolling is fed into the finishing pass for the last rolling. The rolling speed of the finishing pass is adjusted to a steady state of 1.2 m / s, and the rolling force feedback signal is monitored in real time to dynamically correct the roll gap of the finishing pass, so that the cross-sectional dimension accuracy of the produced copper-clad aluminum alloy flat steel is controlled within ±0.05 mm.

[0032] Preferably, in step 104, while the rolling speed of the finished pass is maintained at 1.2 m / s, the emulsion lubrication system uses a 45° spray angle to force lubricate the deformation zone. The impact force generated by the emulsion balances the thickness of the dynamic pressure lubricating oil film between the roll of the finished pass and the contact surface of the copper-clad aluminum alloy composite billet, and simultaneously removes the interface friction heat.

[0033] Preferably, the cantilever mill is equipped with rolling bearings and an independent oil supply unit. The oil supply pressure output by the oil supply unit is controlled within the range of 0.15MPa to 0.25MPa to reduce the rotational resistance fluctuation of the roll system of the cantilever mill. The speed feedback signal of the speed controller of the cantilever mill is used to compensate for the transient rolling force impact load generated by the copper-clad aluminum alloy composite billet at the moment of biting.

[0034] Preferably, in step 101, a multi-roll straightener is used to control the straightness of the copper-clad aluminum alloy composite billet in each dimension, so that when the copper-clad aluminum alloy composite billet enters the positioning and guiding device, the consistency deviation between the geometric center line of the copper-clad aluminum alloy composite billet and the rolling center line of the cantilever mill is within a preset tolerance range, thereby avoiding bite-off defects in the first rolling pass.

[0035] Preferably, the emulsion lubrication system further includes a circulating heat exchange device, which is used to maintain the supply temperature of the emulsion at a constant range of 35°C to 45°C. The emulsion lubrication system also adjusts the emulsion ratio in real time to control the mass percentage concentration of the emulsion within the range of 4% to 6% in order to maintain the shear viscosity stability of the hydrodynamic lubricating oil film.

[0036] Preferably, under the hydrodynamic lubrication state in step 104, the surface roughness of the produced copper-clad aluminum alloy flat steel product is maintained below Ra0.8μm through the physical mapping of the surface morphology of the roll, and the overall flatness of the copper-clad aluminum alloy flat steel product is maintained within 0.1mm / m by the post-tension traction of the finished product pass.

[0037] Preferably, in step 104, the oil supply pressure P of the emulsion is linearly compensated in real time for changes in the rolling speed v of the finished product pass. The oil supply pressure P satisfies the following formula: P = k × v + P0, where P is the oil supply pressure of the emulsion, k is the pressure response coefficient with a value ranging from 0.2 to 0.3, and v is the rolling speed of the finished product pass. The preset base oil supply pressure ranges from 0.11 MPa to 0.19 MPa.

[0038] Preferably, after step 104, the copper-clad aluminum alloy flat steel product is subjected to online alkaline washing, water rinsing and hot air drying in sequence. The alkaline washing process removes the residual emulsion film on the surface of the copper-clad aluminum alloy flat steel product, and the hot air drying process prevents water stains or oxide spots from forming on the surface of the copper-clad aluminum alloy flat steel product.

[0039] Preferably, the hydraulic pressing adjustment mechanism includes a high-frequency servo hydraulic cylinder and a displacement sensor. The high-frequency servo hydraulic cylinder performs closed-loop compensation adjustment of the roll gap in each pass of the nine-pass continuous cold rolling according to the piston stroke signal fed back by the displacement sensor, so as to maintain the single-pass pressing accuracy of the copper-clad aluminum alloy composite billet within the preset control dead zone range.

[0040] Preferably, in step 103, the single-pass reduction rate of the first 8 passes is linearly decreasing with equal deviation, and during the first 8 passes of cold rolling, the micro-tension coefficient of the copper-clad aluminum alloy composite billet between each stand is controlled so that the copper layer and the aluminum matrix in the copper-clad aluminum alloy composite billet undergo synchronous plastic elongation deformation without intermediate annealing.

[0041] Example 1: In the continuous cold rolling of a copper-clad aluminum alloy composite billet with an initial cross-sectional size of 40mm×32mm to a finished flat bar of 30mm×13mm, the inherent intrinsic yield strength difference between the copper layer and the aluminum base layer will induce nonlinear shear stress at the interface between the two phases at the moment of roll bite in the cantilever mill. After the multi-roll straightener establishes a physical constraint benchmark with a straightness of no more than 1.5mm / m, the copper-clad aluminum alloy composite billet is fed into the cantilever mill for continuous 9 passes of non-annealed cold rolling. In the first 8 passes, the speed control system gradually increases the rolling speed from 0.4m / s to 1.0m / s, and simultaneously distributes a single-pass reduction rate decreasing in a gradient from 15% to 8%. In step 103 of continuous rolling, the speed of the frequency conversion drive motor of the adjacent stand is adjusted to maintain the micro-tension coefficient q of the composite billet in the range of 0.10 to 0.15. Here, the micro-tension coefficient q is the ratio of the unit cross-sectional area tension between the stands to the yield strength of the material. The single-pass reduction rate of each pass... according to An arithmetic sequence is used, where n is the pass number from 1 to 8, and Δr is a 1% reduction rate decrease step. The physical value of this step is based on an initial yield strength of 240 MPa, determined through dynamic secondary verification using the current fluctuation amplitude at 500 Hz fed back from the main motor of the rolling mill. When the single-pass current mutation of the main drive motor exceeds 10% of the rated current, the logic determines that the interface shear stress has entered the nonlinear mutation region, and the reduction rate decrease step for the next pass will automatically be increased by a 0.2% correction increment on top of the 1%. By reducing the subsequent deformation rate to offset the residual stress generated by the hardening effect, this distribution method discretizes the total deformation into a plastic rheological process below the interface peeling threshold, allowing the copper layer and aluminum matrix to interpenetrate at the atomic scale and form a continuous bonding interface. This suppresses the deformation mismatch of dissimilar metals without intermediate annealing. This gradient decreasing deformation path transforms the total large deformation into discrete plastic extension, keeping the interfacial shear stress within a single pass below the yield limit of the copper-aluminum composite material, and preventing the physical accumulation of micro-slip at the dissimilar metal interface with increasing pass count.

[0042] When the copper-clad aluminum alloy composite billet enters the finishing pass for the final rolling, the speed control system outputs a frequency control command to maintain the actual rolling speed v at a steady state of 1.2 m / s. At this time, the independent oil supply unit continuously injects oil into the rolling bearings of the cantilever mill at a supply pressure of 0.15 MPa to 0.25 MPa to compensate for transient impact loads. Simultaneously, the circulating emulsion lubrication system uses a 45° spray angle to forcibly spray emulsion into the deformation zone. The actual oil supply pressure P of the emulsion undergoes real-time linear compensation as the actual rolling speed v changes, and the compensation relationship follows the formula... Where P is the oil supply pressure of the emulsion, k is the pressure response coefficient, whose value is limited to 0.2 to 0.3, and v is the actual rolling speed of the finished product pass. The preset base oil supply pressure is limited to a range of 0.11 MPa to 0.19 MPa. In step 104, the peak temperature of the interface in the deformation zone is obtained using an infrared thermal imager with a sampling frequency of not less than 1000 Hz for the finished product pass. As the dynamic calibration input for the pressure response coefficient k, when it is detected... When the temperature remains above 120°C, the speed control system drives the high-frequency servo valve to increase the pressure response coefficient k in increments of 0.01 until... The temperature drops back to a steady-state range below 115℃, locking in the pressure response coefficient k along with the base oil supply pressure. Substitute into the formula The actual oil supply pressure P of the emulsion is determined, where v is the actual rolling speed of the finished product pass. This closed-loop regulation mechanism offsets the viscosity fluctuation of the lubricating oil film caused by high-speed frictional heat, ensuring that the surface roughness of the finished product is stable below Ra0.8μm. This oil supply pressure regulation logic forms a dynamic relationship with the high-speed rolling state of 1.2m / s, generating a continuous dynamic pressure lubricating oil film between the contact surface of the roll and the billet. The fluid dynamic pressure scouring force of the liquid film is used to remove the interfacial frictional heat accumulated in the high-speed deformation zone.

[0043] Based on the physical superposition of the aforementioned decreasing deformation compression distribution mechanism and dynamic fluid thermal balance mechanism, the copper-clad aluminum alloy composite billet completes the synchronous plastic elongation of the copper layer and the aluminum matrix without the intermediate annealing process. The resulting copper-clad aluminum alloy flat steel product has a cross-sectional dimensional tolerance within ±0.05mm, and the overall flatness is converged to within 0.1mm / m through the post-tension traction of the finished product pass. Furthermore, the physical mapping of the roll surface morphology keeps the surface roughness of the finished product below Ra0.8μm. Finally, the copper layer thickness ratio of the finished product is stably in the range of 8% to 15%, and it exhibits an interface physical bonding state without slippage and delamination defects.

[0044] Example 2: When a cantilever rolling mill system faces the continuous rolling condition of copper-clad aluminum alloy composite billets with random thickness fluctuations, the physical delamination caused by the shear stress at the dissimilar metal interface and the imbalance of the frictional thermal field constitute direct physical constraints. Experimental verification was conducted using a physical testing platform equipped with a dynamic fluid pressure sensor and a high-frequency servo valve. The sampling frequency of the dynamic fluid pressure sensor was set to 1000Hz and the measurement accuracy to 0.01MPa. A billet thickness tolerance of ±0.2mm was actively superimposed at the material input end as a background disturbance source to simulate the instantaneous changes in the production environment. To determine the appropriate range of the emulsion oil supply pressure response coefficient k under high-speed shearing conditions, it is necessary to balance the dynamic pressure oil film bearing capacity and the roll bite friction. When the actual rolling speed v reaches the set threshold of 1.2 m / s, if the response coefficient k is too low, the fluid dynamic pressure will be insufficient to offset the heat generated by interfacial friction; if the response coefficient k is too high, it will cause the oil film to become too thick and lead to roll slippage and instability. Based on the fluid dynamics mapping relationship, it is determined that when the response coefficient k is in the range of 0.2 to 0.3, the liquid film scouring force and the heat generation rate reach a physical balance. Based on this, the basic oil supply pressure is determined. The fluid control reference for the sample group of the present invention was constructed by fixing the pressure at 0.15 MPa and selecting the response coefficient k as 0.25.

[0045] The copper-clad aluminum alloy composite billet with an initial cross-sectional size of 40mm × 32mm and a straightness of no more than 1.5mm / m was divided into four independent sample groups for feeding. All four sample groups were rolled in the first eight passes with a decreasing pressure rate ranging from 15% to 8% before being fed into the finishing pass. Under the constraint that the actual rolling speed v in the finishing pass was maintained at 1.2m / s, the sample groups of this invention followed the mathematical equations... Furthermore, using a computational loop with a response coefficient k of 0.25 to dynamically spray the emulsion, the first control group used a constant oil supply pressure of 0.45 MPa to cut off the dynamic compensation link, the second control group set the response coefficient k to 0.1 to construct a pressure undercompensation state, and the third control group set the response coefficient k to 0.4 to construct a pressure overcompensation state. Key parameters collected by physical sensors show that when the sample group of this invention is subjected to an input thickness disturbance of ±0.2 mm, the dynamic pressure oil film thickness between the roll and the billet contact surface stably converges to the range of 2.4 μm to 2.6 μm, and the highest temperature of the deformation zone interface is maintained at 115℃. The dynamic pressure oil film thickness of the first control group fluctuates widely between 0.8 μm and 3.5 μm, and the local temperature extreme value climbs to 165℃ accompanied by local physical peeling of the copper layer. The oil film thickness of the second control group decreases to 1.1 μm due to the lag in fluid pressure response, and the highest interface temperature reaches 148℃. The oil film thickness in the control group exceeded 4.5 μm, triggering a fluid saturation effect and causing a transient loss of the roll gripping force. Measured physical data showed that the surface roughness of the copper-clad aluminum alloy flat steel product output by the present invention was Ra0.6 μm and the overall flatness converged to 0.08 mm / m. As a comparison, the surface roughness of the first and second control groups deteriorated to Ra1.5 μm and Ra1.2 μm, respectively, and the overall flatness of the third control group deteriorated to 0.35 mm / m due to slippage. The dynamic compensation circuit, driven by the real-time change of the emulsion oil supply pressure P by the actual rolling speed v, offsets the transient thermal shock caused by the thickness disturbance at the input end. The dynamic pressure oil film bearing boundary, with the response coefficient k limited to the range of 0.2 to 0.3, inhibits the nonlinear slippage of the dissimilar metal bonding interface. The physical coupling mechanism between this fluid dynamic pressure parameter and the high-speed deformation zone ensures that the surface accuracy and interface bonding state of the produced unannealed copper-clad aluminum alloy flat steel meet the preset physical specifications.

[0046] Example 3: In the continuous non-annealed cold rolling of copper-clad aluminum alloy composite billets, the frictional heat accumulated at the dissimilar metal interface due to intense plastic deformation induces the nucleation of brittle intermetallic compounds. A fixed lubrication supply pressure cannot match the nonlinearly changing interfacial heat flux with increasing rolling passes, leading to localized thermal runaway and physical delamination of the two phases. To address the physical constraint of the unbalanced interfacial heat flux, a dynamic compensation parameter calibration procedure based on data feedback is constructed to establish a fluid control benchmark. The cantilever mill participating in the calibration is equipped with a high-frequency servo valve with a response time of no more than 5ms and an infrared thermal imager with a sampling frequency of 1000Hz, establishing a physical hardware environment to support thermal field monitoring and pressure regulation in the high-speed deformation zone. The calibration procedure synchronously collects the actual rolling speed of the finished pass through a speed control system. Peak temperature at the interface with the deformation zone Where v is the actual rolling speed of the finished product pass. The peak temperature at the interface of the deformation zone is set when the copper-clad aluminum alloy composite billet enters the finishing pass and the actual rolling speed v reaches 1.2 m / s. The high-frequency servo valve then operates according to the preset base oil supply pressure. Spray emulsion into the deformation zone, wherein, The value is limited to 0.15 MPa; the infrared thermal imager continuously monitors the peak temperature of the interface in the deformation zone. The measured thermal field physical quantities are converted into electrical signals and input to the speed control system; the calculation loop in the speed control system compares the peak temperature of the interface in the deformation zone. The temperature was compared with the set critical temperature of 120℃ for brittle phase nucleation.

[0047] If the peak temperature of the deformation zone interface within 10 consecutive sampling periods All temperatures are above 120℃. The speed control system outputs incremental control commands to drive the high-frequency servo valve to adjust the pressure response coefficient k upwards in a reference step of 0.01, where k is a dimensionless proportional factor; the adjustment process continues until the peak temperature of the deformation zone interface is reached. After 50 consecutive sampling cycles, the temperature consistently converges below 115℃. The speed control system then locks the corresponding value as the final operating value of the pressure response coefficient k. A linear relationship between the emulsion supply pressure P and the actual rolling speed v is established through closed-loop calibration. This linear relationship follows the formula... Where P is the actual oil supply pressure of the emulsion. The dynamic pressure oil film bearing boundary established by the calibration procedure absorbs the transient thermal shock caused by high-speed rolling, blocks the thermodynamic path of nucleation of brittle intermetallic compounds, and enables the copper layer and aluminum matrix to maintain a stable metallurgical bonding interface morphology without intermediate annealing.

[0048] Example 4: Under the production conditions of copper-clad aluminum alloy composite billets with fluctuating surface optical emissivity due to different smelting batches, the physical quantities of the thermal field acquired by the infrared thermal imager shift with the oxidation state of the material surface. Before the start of continuous cold rolling, a pre-calibration procedure is performed on-site. The solid temperature and radiation temperature of the first section of billet under static heating state are simultaneously collected by contact thermocouples and infrared thermal imagers. The calculation loop in the speed control system compares the two sets of thermodynamic parameters to extract the optical emissivity correction coefficient characterizing the surface properties of the current batch of material, and incorporates it into the peak temperature of the deformation zone interface. The calculation logic is as follows: The hydraulic pressing adjustment mechanism applies a static physical load to simulate the biting state of the finished product pass. The independent oil supply unit starts the circulating emulsion lubrication system and increases the hydraulic pressure in the pipeline in a stepwise manner when the roll is stationary, until the fluid overflow between the roll and the billet contact surface reaches the preset liquid film coverage benchmark. At this time, the physical value captured by the fluid pressure sensor is extracted and set as the basic oil supply pressure specific to the current batch. Complete baseline calibration.

[0049] After pre-calibration, the copper-clad aluminum alloy composite billet enters the continuous cold rolling sequence. The infrared thermal imager outputs the peak temperature of the interface of the deformation zone after error stripping to the speed control system based on the updated optical emissivity correction coefficient. This thermodynamic feedback data, combined with a specially set base oil supply pressure, Drive dynamic compensation calculations to make the actual oil supply pressure P of the emulsion follow the formula The linear compensation behavior in response to the actual rolling speed v conforms to the inherent physical state of the material; the control mapping that integrates the bottom sensor deviation stripping with the initial fluid state eliminates the initial reference drift caused by cross-batch material differences, locks the adjustment starting point of the pressure response coefficient k within a defined physical boundary, and enables the fluid dynamic pressure feedback network to maintain the thermal equilibrium state of the dissimilar metal interface when dealing with complex incoming material environments, and outputs copper-clad aluminum alloy flat steel that meets dimensional tolerances.

[0050] Example 5: When the cantilever rolling mill system operates under continuous spraying of emulsion and splashed droplets and metal particles adhere to the optical lens surface of the infrared thermal imager, the attenuation of physical radiation flux leads to an increase in the peak temperature of the deformation zone interface received by the speed control system. This generates quantitative distortions that violate actual thermodynamic states. To address the risks of monitoring interruptions and control deviations caused by this environmental disturbance, the speed control system incorporates an online fault-tolerant procedure based on cross-validation of multi-source physical quantities. During the rolling of the finished product pass, its internal calculation loop extracts the temperature drop slope output by the infrared thermal imager and the rolling force feedback signal collected in real time by the force sensor. If the peak temperature of the deformation zone interface measured within 10 consecutive sampling cycles is... The rate of decrease exceeded the physical convection cooling limit, and the rolling force feedback signal at the same time showed a monotonically increasing data characteristic. Based on the physical law of the positive correlation between mechanical friction work and interface temperature rise, the operation loop determined that the monitoring path of the infrared thermal imager encountered physical obstruction and triggered the degradation compensation mechanism.

[0051] After the degradation compensation mechanism is activated, the speed control system blocks the damaged optical temperature feedback node and calls the built-in mechanical thermal mapping algorithm to extract the current rolling force feedback signal and the actual rolling speed v to calculate the total transient mechanical deformation input work. Based on the solidified heat conversion equivalent, it is converted into a theoretical deformation zone interface peak temperature substitute and input into the dynamic adjustment logic of the pressure response coefficient k, thereby maintaining the pressure response coefficient based on the formula. The continuous compensation behavior of the emulsion oil supply pressure P continues until the compression pneumatic unit completes the physical purging of the infrared thermal imager lens and the re-evaluated optical temperature reading recovers to the logic range that matches the rolling force feedback signal. The speed control system then switches the data source back to reading the actual temperature measurement value. This anomaly response procedure eliminates the risk of parameter calibration interruption caused by single-point hardware perception limitations and maintains the physical stiffness required to resist two-phase nonlinear slip at the interface fluid dynamic pressure bearing boundary throughout the high-speed, large-deformation rolling cycle.

[0052] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention.

[0053] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. A method for non-annealing rolling of copper-clad aluminum alloy, characterized in that, Includes the following steps: Step 101: The copper-clad aluminum alloy composite billet is subjected to surface degreasing treatment, physical descaling treatment and multi-roll straightening treatment in sequence to control the straightness of the copper-clad aluminum alloy composite billet within 1.5mm / m, and the straightness is used as the physical constraint reference for subsequent guide biting. Step 102: The straightened copper-clad aluminum alloy composite billet is fed into the positioning guide device of the cantilever mill, the hydraulic pressing adjustment mechanism of the cantilever mill is adjusted to the preset initial pressing parameters, the circulating emulsion lubrication system is started and emulsion is sprayed onto the deformation zone of the cantilever mill, and the initial oil supply pressure of the emulsion is set in the range of 0.35MPa to 0.40MPa. Step 103: The copper-clad aluminum alloy composite billet is subjected to 9 consecutive cold rolling passes using the cantilever mill, with the single-pass reduction rate controlled within the range of 8% to 15% for each pass. During the first 8 passes of cold rolling, the rolling speed is gradually increased from 0.4 m / s to 1.0 m / s using a speed control system, and the single-pass reduction rate for the first 8 passes is distributed in a gradient decreasing from 15% to 8% to offset the accumulation of nonlinear shear stress at the interface between the copper layer and the aluminum matrix by discretizing the total deformation. Step 104: The copper-clad aluminum alloy composite billet after the first 8 passes of cold rolling is fed into the finishing pass for the last rolling. The rolling speed of the finishing pass is adjusted to a steady state of 1.2 m / s, and the rolling force feedback signal is monitored in real time to dynamically correct the roll gap of the finishing pass, so that the cross-sectional dimension accuracy of the produced copper-clad aluminum alloy flat steel is controlled within ±0.05 mm.

2. The method for non-annealing rolling of copper-clad aluminum alloy according to claim 1, characterized in that, In step 104, while the rolling speed of the finished pass is maintained at 1.2 m / s, the emulsion lubrication system uses a 45° spray angle to force lubricate the deformation zone. The impact force generated by the emulsion balances the thickness of the dynamic pressure lubricating oil film between the roll of the finished pass and the contact surface of the copper-clad aluminum alloy composite billet, and simultaneously removes the interface friction heat.

3. The method for non-annealing rolling of copper-clad aluminum alloy according to claim 1, characterized in that, The cantilever mill is equipped with rolling bearings and an independent oil supply unit. The oil supply pressure output by the oil supply unit is controlled within the range of 0.15MPa to 0.25MPa to reduce the rotational resistance fluctuation of the roll system of the cantilever mill. The speed feedback signal of the speed controller of the cantilever mill is used to compensate for the transient rolling force impact load generated by the copper-clad aluminum alloy composite billet at the moment of biting.

4. The method for non-annealing rolling of copper-clad aluminum alloy according to claim 1, characterized in that, In step 101, a multi-roll straightener is used to control the straightness of the copper-clad aluminum alloy composite billet in each dimension, so that when the copper-clad aluminum alloy composite billet enters the positioning and guiding device, the consistency deviation between the geometric center line of the copper-clad aluminum alloy composite billet and the rolling center line of the cantilever mill is within the preset tolerance range, thereby avoiding bite-off defects in the first rolling pass.

5. The method for non-annealing rolling of copper-clad aluminum alloy according to claim 1, characterized in that, The emulsion lubrication system also includes a circulating heat exchange device, which is used to maintain the supply temperature of the emulsion at a constant range of 35°C to 45°C. The emulsion lubrication system also adjusts the emulsion ratio in real time to control the mass percentage concentration of the emulsion within the range of 4% to 6% in order to maintain the shear viscosity stability of the hydrodynamic lubricating oil film.

6. The method for non-annealing rolling of copper-clad aluminum alloy according to claim 2, characterized in that, In the hydrodynamic lubrication state of step 104, the surface roughness of the produced copper-clad aluminum alloy flat steel product is maintained below Ra0.8μm by the physical mapping of the surface morphology of the roll, and the overall flatness of the copper-clad aluminum alloy flat steel product is maintained within 0.1mm / m by the post-tension traction of the finished product pass.

7. The method for non-annealing rolling of copper-clad aluminum alloy according to claim 1, characterized in that, In step 104, the oil supply pressure P of the emulsion is linearly compensated in real time for changes in the rolling speed v of the finished product pass, and the oil supply pressure P satisfies the following formula: Where P is the oil supply pressure of the emulsion, k is the pressure response coefficient, and its value ranges from 0.2 to 0.3; v is the rolling speed of this finished product pass. The preset base oil supply pressure ranges from 0.11 MPa to 0.19 MPa.

8. The method for non-annealing rolling of copper-clad aluminum alloy according to claim 1, characterized in that, Following step 104, the copper-clad aluminum alloy flat steel product is subjected to online alkaline washing, water rinsing, and hot air drying in sequence. The alkaline washing process removes the residual emulsion film on the surface of the copper-clad aluminum alloy flat steel product, and the hot air drying process prevents water stains or oxide spots from forming on the surface of the copper-clad aluminum alloy flat steel product.

9. The method for non-annealing rolling of copper-clad aluminum alloy according to claim 1, characterized in that, The hydraulic reduction adjustment mechanism includes a high-frequency servo hydraulic cylinder and a displacement sensor. The high-frequency servo hydraulic cylinder performs closed-loop compensation adjustment of the roll gap in each of the nine consecutive cold rolling passes based on the piston stroke signal fed back by the displacement sensor, so as to maintain the single-pass reduction accuracy of the copper-clad aluminum alloy composite billet within the preset control dead zone range.

10. A method for non-annealing rolling of copper-clad aluminum alloy according to claim 1, characterized in that, In step 103, the single-pass reduction rate of the first 8 passes is distributed with equal deviation and linear decrease. During the first 8 passes of cold rolling, the micro-tension coefficient of the copper-clad aluminum alloy composite billet between each stand is controlled so that the copper layer and the aluminum matrix in the copper-clad aluminum alloy composite billet undergo synchronous plastic elongation deformation without intermediate annealing.

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