A low-cost preparation method for thin-specification titanium / steel composite plates

Abstract

The present invention provides a low-cost preparation method for thin-gauge titanium / steel composite plates, which includes annealing the titanium plate and the steel plate. After annealing, the hardness of the titanium plate is <150HV, and the hardness of the steel plate is 160-200HV; mechanically grinding the surfaces to be composite of the titanium plate and the steel plate to obtain clean and rough surfaces to be composite; laminating and blanking the mechanically ground titanium plate and steel plate and then performing single-pass cold rolling and composite, with the cold rolling speed being 0.1-0.5m / s and the cold rolling reduction being 30%-48%; after cold rolling and composite, performing diffusion heat treatment on the titanium / steel composite plate under vacuum or protective atmosphere to improve the interfacial bonding strength of the titanium / steel composite plate. This method can prepare titanium / steel composite thin plates with high interfacial bonding quality without welding and hot rolling, and has the advantages of low production cost, simple process, and easy industrial promotion.

Description

Technical Field

[0001] The present invention relates to the technical field of preparation of metal layered composite materials, and in particular to a low-cost preparation method for thin-gauge titanium / steel composite plates. Background Art

[0002] Thin-gauge titanium / steel composite plates combine the excellent corrosion resistance of titanium with the high strength and low cost of steel, and are widely used in petrochemical, architectural decoration, marine engineering and other fields.

[0003] The main methods for preparing titanium / steel composite plates are explosion composite method and hot rolling composite method. The explosion composite method uses the impact force of the explosion to composite the titanium plate and the steel plate together. The process is simple, and the interface bonding strength of the prepared titanium / steel composite plate is high. However, this method also has problems such as environmental pollution and difficulty in continuous production. If the titanium layer is thin, the titanium layer is easily blown through during the explosion. Therefore, the explosion composite method is difficult to prepare titanium / steel composite plates with a thickness of less than 3mm. In order to obtain thin-gauge titanium / steel composite plates, it is generally necessary to perform explosion composite and then roll thinning. However, rolling thinning will lead to a decrease in the quality of the interface bonding.

[0004] The hot rolling composite method involves first treating the surfaces of the titanium and steel plates, then assembling them through vacuum electron beam welding or pinhole vacuuming to ensure interface vacuum, and finally performing multiple hot rolling passes to composite the titanium and steel plates. The hot rolling composite method has the advantages of high production efficiency and the ability to produce wide-width titanium / steel composite plates, and has gradually become the main method for industrially preparing titanium / steel composite plates. However, this method requires vacuum electron beam welding, which places high demands on equipment and a cumbersome process. When the thickness of the titanium / steel composite plate is small, multiple hot rolling passes will lead to a continuous decrease in the interfacial bonding strength, making it unsuitable for the preparation of thin-gauge titanium / steel composite plates.

[0005] In view of the problems of traditional preparation methods such as environmental pollution, high production cost, and difficulty in preparing thin-gauge titanium / steel composite plates, it is of great significance to develop a low-cost preparation method for thin-gauge titanium / steel composite plates. Summary of the Invention

[0006] In view of the above technical problems, a low-cost preparation method for thin-gauge titanium / steel composite plates is provided.

[0007] The technical means adopted in the present invention are as follows:

[0008] A low-cost method for preparing thin-gauge titanium / steel composite plates, comprising:

[0009] S1. Perform vacuum annealing on the titanium plate and the steel plate. It is required that the hardness of the annealed titanium plate is < 150 HV, and the hardness of the steel plate is 160 - 200 HV. The material of the titanium plate is pure titanium, and the model can be, but is not limited to, one of TA1, TA2, TA3 or TA10, with a thickness of 0.2 - 2.0 mm. The steel plate is low-carbon steel, and the model can be, but is not limited to, one of Q235, Q275 or 20#, with a thickness of 1.0 - 4.0 mm. At this time, the titanium plate is in the softest state, which is beneficial to cold rolling plastic deformation. The hardness of the steel plate is slightly higher than that of the titanium plate, which can increase the normal pressure at the interface during cold rolling and is beneficial to the cold rolling composite of the titanium / steel interface. Adjust the hardness of the plates through annealing treatment to reduce the reduction amount required for the cold rolling composite of the titanium / steel billet;

[0010] S2. Mechanically grind the surfaces to be composite of the titanium plate and the steel plate using a grinding wheel or a diamond grinding wheel to obtain clean and rough surfaces to be composite. The grinding stripes are parallel to the width direction, and the surface roughness Ra of the surface to be composite after mechanical grinding is > 2 μm. Grinding the titanium plate and the steel plate using a grinding wheel or a diamond grinding wheel can obtain rough surfaces with the same grinding direction. By controlling the grinding stripe direction and increasing the surface roughness of the plates, the reduction amount required for the cold rolling composite of the titanium / steel billet can be reduced;

[0011] S3. Stack and form billets of the mechanically ground titanium plate and the steel plate, and then perform single-pass cold rolling composite. The cold rolling speed is 0.1 - 0.5 m / s, and the cold rolling reduction amount is 30% - 48%;

[0012] S4. After cold rolling composite, perform diffusion heat treatment on the titanium / steel composite plate under vacuum or in a protective atmosphere to improve the interfacial bonding strength of the titanium / steel composite plate. The method of the diffusion heat treatment is to put it into the furnace in coils and keep it at 500 - 700 °C for 30 - 60 min for diffusion heat treatment. Or the method of the diffusion heat treatment is to perform online heating at 800 - 950 °C for 5 - 15 min for diffusion heat treatment. The thickness of the titanium / steel composite plate is 0.5 - 3.0 mm, and the interfacial bonding strength is > 200 MPa.

[0013] Compared with the prior art, the present invention has the following advantages:

[0014] (1) The method for preparing the titanium / steel composite plate provided by the present invention includes four steps: annealing treatment → surface mechanical grinding → cold rolling composite → diffusion heat treatment. Compared with the traditional hot rolling composite method and explosive composite method, it has the advantages of simple process, short process flow, low equipment requirements, high production efficiency, and easy industrial promotion.

[0015] (2) The present invention reduces the reduction amount required for the cold rolling composite of the titanium / steel billet through reasonable annealing treatment and surface mechanical grinding process, and can guide the cold rolling composite process design of other metal laminated composites.

[0016] (3) The present invention overcomes the defect that it is difficult to prepare thin - gauge titanium / steel composite plates by traditional hot - rolling composite method and explosive composite method.

[0017] For the above reasons, the present invention can be widely promoted in the fields such as the preparation of metal laminated composites. Detailed implementation manners

[0018] It should be noted that, without conflict, the embodiments and features in the embodiments of the present invention can be combined with each other. The present invention will be described in detail below with reference to the embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and in no way restricts the present invention and its application or use. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0019] A low - cost preparation method for thin - gauge titanium / steel composite plates, comprising:

[0020] S1. Perform vacuum annealing treatment on the titanium plate and the steel plate. It is required that the hardness of the annealed titanium plate is < 150 HV, and the hardness of the steel plate is 160 - 200 HV; the material of the titanium plate is pure titanium, and the model can be but is not limited to one of TA1, TA2, TA3 or TA10, with a thickness of 0.2 - 2.0 mm; the steel plate is low - carbon steel, and the model can be but is not limited to one of Q235, Q275 or 20#, with a thickness of 1.0 - 4.0 mm. At this time, the titanium plate is in the softest state, which is beneficial to cold - rolling plastic deformation. The hardness of the steel plate is slightly higher than that of the titanium plate, which can increase the normal pressure at the interface during cold - rolling and is beneficial to the cold - rolling composite of the titanium / steel interface. Adjust the hardness of the plates through annealing treatment to reduce the reduction amount required for the cold - rolling composite of the titanium / steel billet;

[0021] S2. Mechanically polish the surfaces to be composite of the titanium plate and the steel plate with a grinding wheel or a diamond grinding wheel to obtain clean and rough surfaces to be composite; the grinding stripes are parallel to the width direction, and the surface roughness Ra of the surface to be composite after mechanical polishing is > 2 μm. Using a grinding wheel or a diamond grinding wheel to polish the titanium plate and the steel plate can obtain rough surfaces with the same grinding direction. By controlling the direction of the grinding stripes and increasing the surface roughness of the plates, the reduction amount required for the cold - rolling composite of the titanium / steel billet can be reduced;

[0022] S3. Stack and form a billet with the mechanically polished titanium plate and steel plate, and then perform single - pass cold - rolling composite. The cold - rolling speed is 0.1 - 0.5 m / s, and the cold - rolling reduction amount is between 30% and 48%;

[0023] S4. After cold rolling and compounding, the titanium / steel composite plate is subjected to diffusion heat treatment under vacuum or protective atmosphere to improve the interfacial bonding strength of the titanium / steel composite plate. The diffusion heat treatment method is to put it into the furnace in coils and keep it at 500-700 °C for 30-60 min for diffusion heat treatment. Or the diffusion heat treatment method is to perform diffusion heat treatment by online heating at 800-950 °C for 5-15 min. The thickness of the titanium / steel composite plate is 0.5-3.0 mm, and the interfacial bonding strength > 200 MPa.

[0024] Example 1

[0025] A low-cost preparation method for a thin-specification titanium / steel composite plate. The cladding material is TA2 pure titanium with an initial thickness of 1.0 mm, and the base material is Q235 low-carbon steel with an initial thickness of 2.0 mm. First, the plates are subjected to vacuum annealing treatment. The annealing regime for the TA2 titanium plate is to keep it at 750 °C for 0.5 h and then cool it in the furnace, and the annealing regime for the Q235 steel plate is to keep it at 850 °C for 0.5 h and then cool it in the furnace. Then, the surfaces of the plates are transversely polished with a 48-mesh grinding wheel, and the grinding stripes are parallel to the width direction of the plates. The surface roughnesses of the titanium plate and the steel plate to be compounded after grinding are 4.3 μm and 6.8 μm respectively. Then, the mechanically polished titanium plate and steel plate are stacked and assembled into a blank and pre-compounded by single-pass cold rolling. The cold rolling speed is 0.1 m / s, and the cold rolling reduction rate is 36%, obtaining a titanium / steel composite plate with a thickness of 1.9 mm. Finally, the titanium / steel composite plate is heated to 850 °C online through a roller hearth furnace, and the time for the titanium / steel composite plate to pass through the roller hearth furnace is controlled at about 10 min. The interfacial bonding strength of the titanium / steel composite plate after diffusion heat treatment is 246 MPa.

[0026] Example 2

[0027] A low-cost preparation method for a thin-specification titanium / steel composite plate. The cladding material is TA1 pure titanium with an initial thickness of 0.2 mm for the titanium plate, and the base material is Q235 low-carbon steel with an initial thickness of 1.0 mm for the steel plate. First, the plates are subjected to vacuum annealing. The annealing regime for the TA1 titanium plate is to hold at 750 °C for 0.5 h and then cool in the furnace, and the annealing regime for the Q235 steel plate is to hold at 850 °C for 0.5 h and then cool in the furnace. Then, the surfaces of the plates are ground transversely with a 60-mesh grinding wheel, and the grinding stripes are parallel to the width direction of the plates. The surface roughnesses of the titanium plate and the steel plate to be composite after grinding are 2.5 mm and 2.9 mm respectively. Next, the mechanically ground titanium plate and steel plate are stacked and assembled into a billet and then pre-compounded by single-pass cold rolling. The cold rolling speed is 0.3 m / s, and the cold rolling reduction rate is 30%, obtaining a coiled titanium / steel composite strip with a thickness of 0.84 mm. Finally, the coiled titanium / steel composite strip is placed in a vacuum heating furnace and held at 700 °C for 30 min. After diffusion heat treatment, the titanium / steel composite strip does not delaminate at the interface after repeated bending, and the interface bonding is good (since the thickness of the titanium / steel composite plate in this example is less than 1 mm, the interface bonding strength cannot be measured, and the interface bonding quality is inspected by the bending method according to the national standard).

[0028] Example 3

[0029] A low-cost preparation method for a thin-specification titanium / steel composite plate. The cladding material is TA2 pure titanium with an initial thickness of 1.0 mm for the titanium plate, and the base material is 20# steel plate with an initial thickness of 3.0 mm for the steel plate. First, the plates are annealed. The annealing regime for the TA2 titanium plate is to hold at 750 °C for 0.5 h and then cool in the furnace, and the annealing regime for the 20# steel plate is to hold at 860 °C for 0.5 h and then cool in the furnace. Then, the surfaces of the plates are ground transversely with a 40-mesh diamond grinding wheel, and the grinding stripes are parallel to the width direction of the plates. The surface roughnesses of the titanium plate and the steel plate to be composite after grinding are 5.0 mm and 7.3 mm respectively. Next, the mechanically ground titanium plate and steel plate are stacked and assembled into a billet and then pre-compounded by single-pass cold rolling. The cold rolling speed is 0.1 m / s, and the cold rolling reduction rate is 45%, obtaining a titanium / steel composite plate with a thickness of 2.2 mm. Finally, the titanium / steel composite plate is heated to 900 °C online through a roller hearth furnace, and the time for the titanium / steel composite plate to pass through the roller hearth furnace is controlled at about 8 min. The interface bonding strength of the titanium / steel composite plate after diffusion heat treatment is 230 MPa.

[0030] Example 4

[0031] A low-cost preparation method for thin-specification titanium / steel composite plates. The cladding material is TA1 pure titanium with an initial thickness of 2.0 mm for the titanium plate, and the base material is Q235 steel plate with an initial thickness of 4.0 mm for the steel plate. First, anneal the plates. The annealing regime for the TA1 titanium plate is to hold at 750 °C for 0.5 h and then cool in the furnace, and the annealing regime for the Q235 steel plate is to hold at 850 °C for 1.0 h and then cool in the furnace. Then, transversely grind the surfaces of the plates with a 48-mesh diamond grinding wheel. The grinding stripes are parallel to the width direction of the plates. The surface roughness of the titanium plate and the steel plate to be composite after grinding are 4.5 mm and 6.3 mm respectively. Then, stack and form blanks of the mechanically ground titanium plate and steel plate and perform single-pass cold rolling for pre-composite. The cold rolling speed is 0.1 m / s, and the cold rolling reduction rate is 48%, obtaining a titanium / steel composite plate with a thickness of 3.12 mm. Finally, heat the titanium / steel composite plate online to 950 °C in a roller hearth furnace. The time for the titanium / steel composite plate to pass through the roller hearth furnace is controlled at about 5 min. The interfacial bonding strength of the titanium / steel composite plate after diffusion heat treatment is 210 MPa.

[0032] Example 5

[0033] A low-cost preparation method for thin-specification titanium / steel composite plates. The cladding material is TA2 pure titanium with an initial thickness of 1.0 mm for the titanium plate, and the base material is Q235 steel plate with an initial thickness of 2.0 mm for the steel plate. First, anneal the plates. The annealing regime for the TA2 titanium plate is to hold at 750 °C for 0.5 h and then cool in the furnace, and the annealing regime for the Q235 steel plate is to hold at 850 °C for 0.5 h and then cool in the furnace. Then, transversely grind the surfaces of the plates with a 48-mesh diamond grinding wheel. The grinding stripes are parallel to the width direction of the plates. The surface roughness of the titanium plate and the steel plate to be composite after grinding are 4.0 mm and 5.3 mm respectively. Then, stack and form blanks of the mechanically ground titanium plate and steel plate and perform single-pass cold rolling for pre-composite. The cold rolling speed is 0.5 m / s, and the cold rolling reduction rate is 45%, obtaining a titanium / steel composite strip with a thickness of 1.65 mm. Finally, place the coiled titanium / steel composite strip in a vacuum heating furnace and hold at 500 °C for 60 min. The interfacial bonding strength of the titanium / steel composite plate after diffusion heat treatment is 226 MPa.

[0034] Finally, it should be noted that: The above embodiments are only used to illustrate the technical solutions of the present invention, not to limit them; Although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: They can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; And these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A low-cost preparation method for thin-specification titanium / steel composite plates, characterized in that, Including: S1. The titanium plate material is pure titanium with a thickness of 0.2 - 2.0 mm, and the steel plate is low-carbon steel with a thickness of 1.0 - 4.0 mm. Anneal the titanium plate and the steel plate. After annealing, the hardness of the titanium plate is < 150 HV, and the hardness of the steel plate is 160 - 200 HV; S2. Mechanically polish the surfaces to be compounded of the titanium plate and the steel plate to obtain clean and rough surfaces to be compounded. The polishing stripes are parallel to the width direction. After mechanical polishing, the surface roughness Ra of the surface to be compounded is > 2 μm; S3. Stack and form blanks of the mechanically polished titanium plate and steel plate, and then perform single-pass cold rolling compounding. The cold rolling speed is 0.1 - 0.5 m / s, and the cold rolling reduction is 30% - 48%; S4. After cold rolling compounding, perform diffusion heat treatment on the titanium / steel composite plate under vacuum or protective atmosphere to improve the interfacial bonding strength of the titanium / steel composite plate. The diffusion heat treatment method is to perform diffusion heat treatment by online heating at 800 - 950 °C for 5 - 15 min, or the diffusion heat treatment method is to put it into the furnace in coils and keep it warm at 500 - 700 °C for 30 - 60 min for diffusion heat treatment.

2. The low-cost preparation method of a thin-specification titanium / steel composite plate according to claim 1, wherein, In S4, the thickness of the titanium / steel composite plate is 0.5 - 3.0 mm, and the interfacial bonding strength is > 200 MPa.

3. The low-cost preparation method of a thin-specification titanium / steel composite plate according to claim 1, characterized in that, In S1, the pure titanium model is one of TA1, TA2, TA3 or TA10; the low-carbon steel model is one of Q235, Q275 or 20#.

4. A low-cost preparation method for a thin-gauge titanium / steel composite plate according to claim 1, characterized in that, In step S2, use a grinding wheel or a diamond grinding wheel to mechanically polish the surfaces to be compounded of the titanium plate and the steel plate.