Titanium-steel clad steel plate with copper-nickel alloy as middle layer and preparation method of titanium-steel clad steel plate

Abstract

The invention relates to the technical field of metal materials, and provides a titanium-steel clad steel plate with a copper-nickel alloy as a middle layer and a preparation method, the titanium-steel clad steel plate comprises a steel material, and the copper-nickel alloy middle layer and a titanium material which are sequentially arranged on the surface of the steel material; and the copper-nickel alloy intermediate layer consists of the following components in percentage by weight: 40-60% of Cu and the balance of Ni and other inevitable impurities. By means of the technical scheme, the problem that in the prior art, the shear strength of the titanium-steel composite steel plate is low is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of metal materials, and in particular to a titanium-steel composite steel plate with a copper-nickel alloy as an intermediate layer and a preparation method thereof. Background Art

[0002] Titanium-steel composite plates combine the excellent corrosion resistance of titanium with the high strength and low cost of steel, offering promising applications in fields such as marine engineering and manufacturing. These plates can be produced through welding or rolling. However, regardless of the method used, the interface strength between titanium and steel is often suboptimal. This is because the brittle β-phase solid solution and TiFe and TiFe2 intermetallic compounds formed between titanium and steel at high temperatures are easily crushed by external forces, hindering the bonding between the two materials.

[0003] Rolling cladding is an ideal approach to achieving high shear strength titanium-steel composite plates. Controlling the heating temperature of the steel rolling mill reduces the formation of β-phase solid solution and TiFe and TiFe2 intermetallic compounds. Generally, the heating temperature needs to be limited to below 880°C. However, lowering the heating temperature increases the load on the rolling mill and narrows the rolling process window. In actual production, the shear strength of titanium-steel composite plates is less than 140 MPa.

[0004] In actual production, industrial interstitial-free steel (IF steel) is often used as an intermediate layer between titanium and steel. Although the carbon content in IF steel is very low, which limits the formation of β-phase solid solutions, the presence of TiFe and TiFe2 intermetallic compounds is still significant. Consequently, the bonding performance of the titanium-steel composite plate remains suboptimal. While the shear strength can barely reach 140 MPa, this is significantly lower than the 190 MPa shear strength requirement for premium grades.

[0005] Therefore, there is an urgent need to develop a titanium-steel composite steel plate with excellent shear strength. Summary of the Invention

[0006] The present invention provides a titanium-steel composite steel plate with a copper-nickel alloy as an intermediate layer and a preparation method thereof, which solves the problem of low shear strength of the titanium-steel composite steel plate in the related art.

[0007] The technical solutions of the present invention are as follows: The present invention provides a titanium-steel composite steel plate with a copper-nickel alloy as an intermediate layer, comprising a steel material, a copper-nickel alloy intermediate layer and a titanium material sequentially arranged on the surface of the steel material; The copper-nickel alloy intermediate layer is composed of the following components in weight percentage: 40% to 60% Cu, and the remainder is Ni and other inevitable impurities.

[0008] As a further technical solution, the copper-nickel alloy intermediate layer is composed of the following components in weight percentage: 55% Cu, and the rest is Ni and other inevitable impurities.

[0009] In the present invention, the composition of the copper-nickel alloy intermediate layer is adjusted, taking into account not only the shear strength of the titanium-steel composite plate but also the high price of nickel, a precious metal element. When the copper-nickel alloy intermediate layer is composed of the following components by weight: 55% Cu, with the remainder being nickel and other unavoidable impurities, not only is brittle phase generation eliminated, but costs are also minimized.

[0010] As a further technical solution, the steel material includes one of Q235 steel, Q355 steel, Q390 steel, Q420 steel, and Q460 steel.

[0011] As a further technical solution, the titanium material includes TA1 pure titanium or TA2 pure titanium.

[0012] The present invention also provides a method for preparing a titanium-steel composite steel plate with a copper-nickel alloy as an intermediate layer, which is used to prepare the titanium-steel composite steel plate, comprising the following steps: S1. Assembling billets: Grooving two steel pieces, placing a copper-nickel alloy intermediate layer and a titanium material in the grooves of the two steel pieces, respectively, to obtain two single billets. After applying a release agent on the titanium material surfaces of the two single billets, the billets are buckled together to obtain an assembled billet; S2, welding: welding the seams of the blank to obtain a welded blank; S3, heating: heating the welded blank to obtain a heated blank; S4, rolling and splitting: the heated billet is rolled, cut, and split into two titanium-steel composite steel plates.

[0013] In this invention, given the significant difference in thermal expansion coefficients between titanium and steel, a single titanium-steel composite plate inevitably warps to one side during production, even preventing it from entering the straightening rollers. By designing the symmetrical distribution of the blanks, the stress caused by thermal expansion is eliminated, allowing the titanium-steel composite plate to maintain a good shape. Furthermore, after cutting, two titanium-steel composite plates are obtained, improving production efficiency.

[0014] As a further technical solution, in step S1, the isolation agent is magnesium oxide.

[0015] In the present invention, the magnesium oxide separator can withstand a high temperature of more than 1000° C., ensuring that the two single billets in the billet assembly maintain independent tensile deformation during the rolling process.

[0016] As a further technical solution, in step S2, the welding is vacuum electron beam welding. During the vacuum electron beam welding, the welding current is 350-450 mA and the welding speed is 6-8 mm / s.

[0017] In the present invention, vacuum electron beam welding is adopted to fundamentally reduce the oxidation of the steel and titanium material surfaces caused by welding, thereby improving the welding quality.

[0018] As a further technical solution, in step S3, the heating temperature is 925-945° C. and the heating time is 3.5-5.5 hours.

[0019] In the present invention, since the minimum forming temperatures of the intermediate phases of Cu, Ni, and Ti are all above 955°C, the heating temperature is determined to be 925-945°C. This heating temperature significantly expands the range of the rolling process and is particularly suitable for titanium-steel composite steel plates with a wide range of specifications.

[0020] As a further technical solution, in step S4, secondary heating is also included after the rolling.

[0021] As a further technical solution, during the secondary heating, the temperature is 925-945° C. and the time is 5-6 hours.

[0022] The working principle and beneficial effects of the present invention are: In the present invention, by providing a copper-nickel alloy intermediate layer between the steel and titanium materials, the diffusion of C and Fe in the steel into the titanium material can be effectively prevented. This solves the problem of brittle phases such as β-phase solid solution and TiFe and TiFe2 intermetallic compounds produced during the production of traditional titanium-steel composite plates, thereby improving the shear strength of the titanium-steel composite plates. In addition, by limiting the Cu content in the copper-nickel alloy intermediate layer, the present invention avoids the generation of other brittle phases, significantly improving the shear strength of the titanium-steel composite plates. In terms of weight percentage, when the Cu content is less than 40%, the Ti2Cu brittle phase will be generated; when the Cu content is greater than 60%, the TiCu and Ti2Cu3 brittle phases will be generated. Therefore, only when the Cu content is between 40% and 60% can the provision of a copper-nickel alloy intermediate layer significantly improve the shear strength of the titanium-steel composite plates. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0024] Figure 1 This is the metallographic diagram of the titanium-steel composite steel plate prepared in Example 2. DETAILED DESCRIPTION

[0025] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention.

[0026] Example 1 A method for preparing a titanium-steel composite steel plate with a copper-nickel alloy as an intermediate layer comprises the following steps: S1. Assembling billets: Grooving two steel pieces, placing a copper-nickel alloy intermediate layer and a titanium material in the grooves of the two steel pieces, respectively, to obtain two single billets. Applying a 1.3 mm thick magnesium oxide release agent to the titanium material surfaces of the two single billets, the billets are then assembled by buckling. S2. Welding: vacuum electron beam welding is performed on the seams of the blank to obtain a welded blank; S3, heating: heating the welded blank to obtain a heated blank; S4, rolling and splitting: the heated billet is rolled, cut, and split into two 12 mm thick titanium steel composite plates; The steel material is Q235 steel, with dimensions of 3400mm×2100mm×165mm; the buckle slot dimensions are 3300mm×2000mm×30mm; the copper-nickel alloy intermediate layer is composed of the following components by weight percentage: Cu 40%, the rest Ni and other unavoidable impurities, with dimensions of 3290mm×1990mm×0.7mm; the titanium material is TA2 pure titanium, with dimensions of 3290mm×1990mm×28mm; During vacuum electron beam welding, the vacuum degree of the vacuum chamber is 4×10 -4 Torr, the vacuum degree of the electron gun is 8×10 - 6 Torr, voltage is 60kV, focusing cable is 560mA, welding current is 350mA, welding speed is 8mm / s; During heating, the temperature is 925℃ and the time is 5.5h. During rolling, the width is expanded to 2900mm.

[0027] Example 2 A method for preparing a titanium-steel composite steel plate with a copper-nickel alloy as an intermediate layer comprises the following steps: S1. Assembling billets: Grooving two steel pieces, placing a copper-nickel alloy intermediate layer and a titanium material in the grooves of the two steel pieces, respectively, to obtain two single billets. Applying a 2.5 mm thick magnesium oxide release agent to the titanium material surfaces of the two single billets, the billets are then buckled together to obtain an assembled billet; S2. Welding: vacuum electron beam welding is performed on the seams of the blank to obtain a welded blank; S3, heating: heating the welded blank to obtain a heated blank; S4, rolling and splitting: After the heated billet is rolled, it is cut and split into two 10mm thick titanium steel composite plates. The metallographic diagram is as follows: Figure 1 As shown in the figure, it can be seen that even if the heating temperature is as high as 945℃, the interface bonding of titanium steel composite plate is still good; The steel material is Q355 steel, with dimensions of 3160mm×2000mm×120mm; the buckle slot dimensions are 2950mm×1900mm×27mm; the copper-nickel alloy intermediate layer is composed of the following components by weight percentage: Cu 40%, the remainder being Ni and other unavoidable impurities, with dimensions of 3150mm×1895mm×0.5mm; the titanium material is TA1 pure titanium, with dimensions of 3150mm×1895mm×24mm; During vacuum electron beam welding, the vacuum degree of the vacuum chamber is 4×10 -4 Torr, the vacuum degree of the electron gun is 8×10 - 6 Torr, voltage is 60kV, focusing cable is 560mA, welding current is 450mA, welding speed is 6mm / s; During heating, the temperature is 945°C and the time is 6 hours. During rolling, the width is expanded to 2500 mm.

[0028] Example 3 A method for preparing a titanium-steel composite steel plate with a copper-nickel alloy as an intermediate layer comprises the following steps: S1. Assembling billets: Grooving two steel pieces, placing a copper-nickel alloy intermediate layer and a titanium material in the grooves of the two steel pieces, respectively, to obtain two single billets. Applying a 1.3 mm thick magnesium oxide release agent to the titanium material surfaces of the two single billets, the billets are then assembled by buckling. S2. Welding: vacuum electron beam welding is performed on the seams of the blank to obtain a welded blank; S3, heating: heating the welded blank to obtain a heated blank; S4, rolling and splitting: the heated billet is rolled, cut and split into two 9mm thick ultra-wide titanium steel composite plates; The steel material is Q235 steel, with dimensions of 3480mm×2260mm×140mm; the buckle slot dimensions are 3380mm×2160mm×34mm; the copper-nickel alloy intermediate layer is composed of the following components by weight percentage: Cu 55%, the rest Ni and other unavoidable impurities, with dimensions of 3370mm×2150mm×0.7mm; the titanium material is TA2 pure titanium, with dimensions of 3370mm×2150mm×32mm; During vacuum electron beam welding, the vacuum degree of the vacuum chamber is 4×10 -4 Torr, the vacuum degree of the electron gun is 8×10 - 6 Torr, voltage is 60kV, focusing cable is 560mA, welding current is 400mA, welding speed is 7mm / s; During heating, the temperature is 935℃ and the time is 5h. During rolling, the width is expanded to 4600mm.

[0029] Example 4 A method for preparing a titanium-steel composite steel plate with a copper-nickel alloy as an intermediate layer comprises the following steps: S1. Assembling billets: Grooving two steel pieces, placing a copper-nickel alloy intermediate layer and a titanium material in the grooves of the two steel pieces, respectively, to obtain two single billets. Applying a 1 mm thick magnesium oxide release agent to the titanium material surfaces of the two single billets, the billets are then buckled together to obtain an assembled billet; S2. Welding: vacuum electron beam welding is performed on the seams of the blank to obtain a welded blank; S3, heating: heating the welded blank to obtain a heated blank; S4, rolling and splitting: the heated billet is rolled once, heated again, cut, and split into two 24mm thick ultra-thick titanium steel composite plates; The steel material is Q235 steel, with dimensions of 3165mm×2545mm×348mm; the buckle slot dimensions are 3065mm×2445mm×34mm; the copper-nickel alloy intermediate layer is composed of the following components by weight percentage: Cu 55%, the rest Ni and other unavoidable impurities, with dimensions of 3055mm×2435mm×1mm; the titanium material is TA2 pure titanium, with dimensions of 3055mm×2435mm×32mm; During vacuum electron beam welding, the vacuum degree of the vacuum chamber is 4×10 -4 Torr, the vacuum degree of the electron gun is 8×10 - 6 Torr, voltage is 60kV, focusing cable is 560mA, welding current is 400mA, welding speed is 7mm / s; During the first heating, the temperature is 940℃ and the time is 3.5h; during the second heating, the temperature is 925℃ and the time is 6h. During rolling, the width is expanded to 2880mm.

[0030] Comparative Example 1 The only difference between this comparative example and Example 1 is that in this comparative example, no copper-nickel alloy intermediate layer is placed, and the buckle groove size is 3300 mm×2000 mm×29.3 mm.

[0031] Comparative Example 2 The only difference between this comparative example and Example 1 is that in this comparative example, the copper-nickel alloy intermediate layer is replaced by DC05 type IF steel of equal size.

[0032] Comparative Example 3 The only difference between this comparative example and Example 1 is that in this comparative example, the copper-nickel alloy intermediate layer is composed of the following components in weight percentage: 25% Cu, and the remainder Ni and other inevitable impurities.

[0033] Comparative Example 4 The only difference between this comparative example and Example 1 is that in this comparative example, the copper-nickel alloy intermediate layer is composed of the following components in weight percentage: 75% Cu, and the rest Ni and other inevitable impurities.

[0034] The titanium-steel composite plates prepared in Examples 1-4 and Comparative Examples 1-4 were tested for shear strength in accordance with GB / T 6396-2008, "Test Methods for Mechanical and Processing Properties of Composite Steel Plates." The arithmetic mean of the six test specimens was used as the final result, expressed in MPa. The test results are shown in Table 1 below.

[0035] Table 1 Shear strength of titanium steel composite plate

[0036] From the comparison between Example 1 and Comparative Examples 1 to 4, it can be seen that by providing a copper-nickel alloy intermediate layer between the steel and the titanium material and ensuring that the Cu content is 40% to 60%, the shear strength of the titanium-steel composite steel plate can be significantly improved.

[0037] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A titanium-steel composite steel plate with a copper-nickel alloy as an intermediate layer, characterized in that: It comprises a steel material and a copper-nickel alloy intermediate layer and a titanium material sequentially arranged on the surface of the steel material; The copper-nickel alloy intermediate layer is composed of the following components in weight percentage: 40% to 60% Cu, and the remainder is Ni and other inevitable impurities.

2. The titanium-steel composite steel plate with a copper-nickel alloy as an intermediate layer according to claim 1, characterized in that: The copper-nickel alloy intermediate layer is composed of the following components in weight percentage: 55% Cu, and the remainder Ni and other inevitable impurities.

3. The titanium-steel composite steel plate with a copper-nickel alloy as an intermediate layer according to claim 1, characterized in that: The steel material includes one of Q235 steel, Q355 steel, Q390 steel, Q420 steel and Q460 steel.

4. The titanium-steel composite steel plate with a copper-nickel alloy as an intermediate layer according to claim 1, characterized in that: The titanium material includes TA1 pure titanium or TA2 pure titanium.

5. A method for preparing a titanium-steel composite steel plate with a copper-nickel alloy as an intermediate layer, for preparing the titanium-steel composite steel plate according to any one of claims 1 to 4, characterized in that: The following steps are involved: S1. Assembling billets: Grooving two steel pieces, placing a copper-nickel alloy intermediate layer and a titanium material in the grooves of the two steel pieces, respectively, to obtain two single billets. After applying a release agent on the titanium material surfaces of the two single billets, the billets are buckled together to obtain an assembled billet; S2, welding: welding the seams of the blank to obtain a welded blank; S3, heating: heating the welded blank to obtain a heated blank; S4, rolling and splitting: the heated billet is rolled, cut, and split into two titanium-steel composite steel plates.

6. The method for preparing a titanium-steel composite steel plate with a copper-nickel alloy as an intermediate layer according to claim 5, characterized in that: In step S1, the isolation agent is magnesium oxide.

7. The method for preparing a titanium-steel composite steel plate with a copper-nickel alloy as an intermediate layer according to claim 5, characterized in that: In step S2, the welding is vacuum electron beam welding. During the vacuum electron beam welding, the welding current is 350-450 mA and the welding speed is 6-8 mm / s.

8. The method for preparing a titanium-steel composite steel plate with a copper-nickel alloy as an intermediate layer according to claim 5, characterized in that: In step S3, the heating temperature is 925-945° C. and the heating time is 3.5-5.5 hours.

9. The method for preparing a titanium-steel composite steel plate with a copper-nickel alloy as an intermediate layer according to claim 5, characterized in that: In step S4, secondary heating is also performed after the rolling.

10. The method for preparing a titanium-steel composite steel plate with a copper-nickel alloy as an intermediate layer according to claim 9, characterized in that: During the secondary heating, the temperature is 925-945° C. and the time is 5-6 hours.

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