A composite material for improving the toughness of paint surfaces and a musical instrument comprising the composite material.

Abstract

This invention discloses a composite material for improving the toughness of paint surfaces. The composite material comprises: a first mixed oxide layer on a metal substrate, wherein the first mixed oxide layer comprises Al2O3, La2O3, and Gd2O3; a second mixed oxide layer on the first mixed oxide layer, wherein the second mixed oxide layer comprises Al2O3, La2O3, and CeO2; a third mixed oxide layer on the second mixed oxide layer, wherein the third mixed oxide layer comprises Al2O3, Gd2O3, and CeO2; and a fourth mixed oxide layer on the third mixed oxide layer, wherein the fourth mixed oxide layer comprises Al2O3, Dy2O3, and Gd2O3. The composite material of this invention can enhance the plasticity and fracture toughness of the coating, thereby preventing brittle peeling of the paint surface under impacts such as dropping.

Description

Technical Field

[0001] This invention relates to the field of metal coating technology, and in particular to a composite material for improving the toughness of a paint surface and a musical instrument comprising the composite material. Background Technology

[0002] In early childhood education, music education plays an indispensable role. To stimulate young children's interest in learning, early childhood education institutions commonly use small metal percussion instruments designed specifically for children, such as bells, maracas, and cymbals. These instruments not only require pure sound quality, but also, because their users are young children with limited cognitive and behavioral control abilities, their design must fully consider the unavoidable unexpected behaviors such as dropping and bumping during use. Currently, to improve the aesthetics and corrosion resistance of metal instruments and avoid potential scratches to children from the metal surface, manufacturers usually apply decorative or protective paint layers to the metal substrate. However, existing metal surface paint technologies primarily focus on performance optimization in terms of corrosion resistance, weather resistance, or gloss, and the flexibility and impact resistance of the paint film often fail to meet the specific requirements of early childhood education. Summary of the Invention

[0003] This invention relates to a composite material for improving the toughness of paint finishes on metal substrates and its applications. The core of this composite material lies in the sequential deposition of four specific mixed oxide layers on a metal substrate: the first layer comprises Al₂O₃, La₂O₃, and Gd₂O₃; the second layer comprises Al₂O₃, La₂O₃, and CeO₂; the third layer comprises Al₂O₃, Gd₂O₃, and CeO₂; and the fourth layer comprises Al₂O₃, Dy₂O₃, and Gd₂O₃. Each layer is deposited using a magnetron sputtering process, with controlled component mass ratios and process parameters. This method can significantly improve the toughness and impact resistance of the paint finish. First, the multilayer mixed oxide structure forms a gradient composite effect at the microscopic level through the synergistic effect of different rare earth oxides (such as La2O3, Gd2O3, CeO2, and Dy2O3) and Al2O3, effectively dispersing and absorbing external impact energy and inhibiting crack initiation and propagation. Second, the introduction of rare earth elements may enhance the plasticity and fracture toughness of the coating through phase transformation toughening and grain boundary strengthening mechanisms, thereby preventing the paint surface from brittlely peeling off under impacts such as dropping.

[0004] This invention provides a composite material for improving the toughness of paint surfaces, the composite material comprising:

[0005] A first mixed oxide layer on a metal substrate, wherein the first mixed oxide layer comprises Al2O3, La2O3 and Gd2O3;

[0006] A second mixed oxide layer on a first mixed oxide layer, wherein the second mixed oxide layer comprises Al2O3, La2O3 and CeO2;

[0007] A third mixed oxide layer on the second mixed oxide layer, wherein the third mixed oxide layer comprises Al2O3, Gd2O3 and CeO2;

[0008] A fourth mixed oxide layer on top of the third mixed oxide layer, wherein the fourth mixed oxide layer comprises Al2O3, Dy2O3 and Gd2O3.

[0009] In a preferred embodiment, the first mixed oxide layer is deposited on a metal substrate by magnetron sputtering. The target material for depositing the first mixed oxide layer is a first mixed oxide target material composed of Al2O3, La2O3 and Gd2O3, wherein the mass ratio of Al2O3, La2O3 and Gd2O3 in the first mixed oxide target material is 100:(2-3):(0.5-1).

[0010] In a preferred embodiment, the process parameters for depositing the first mixed oxide layer are as follows: the power supply type is an RF power supply, the sputtering power is 60-80W, the sputtering voltage is 40-50V, the argon flow rate is 20-30sccm, and the sputtering temperature is 80-100℃.

[0011] In a preferred embodiment, the second mixed oxide layer is deposited on the first mixed oxide layer by magnetron sputtering. The target material for depositing the second mixed oxide layer is a second mixed oxide target material composed of Al2O3, La2O3 and CeO2, wherein the mass ratio of Al2O3, La2O3 and CeO2 in the second mixed oxide target material is 100:(0.5-1):(2-3).

[0012] In a preferred embodiment, the process parameters for depositing the second mixed oxide layer are as follows: the power supply type is an RF power supply, the sputtering power is 70-90W, the sputtering voltage is 60-70V, the argon flow rate is 20-30sccm, and the sputtering temperature is 80-100℃.

[0013] In a preferred embodiment, the third mixed oxide layer is deposited on the second mixed oxide layer by magnetron sputtering. The target material for depositing the third mixed oxide layer is a third mixed oxide target material composed of Al2O3, Gd2O3 and CeO2, wherein the mass ratio of Al2O3, Gd2O3 and CeO2 in the third mixed oxide target material is 100:(1.5-3):(2-3).

[0014] In a preferred embodiment, the process parameters for depositing the third mixed oxide layer are as follows: the power supply type is an RF power supply, the sputtering power is 70-90W, the sputtering voltage is 60-70V, the argon flow rate is 20-30sccm, and the sputtering temperature is 80-100℃.

[0015] In a preferred embodiment, the fourth mixed oxide layer is deposited on the third mixed oxide layer by magnetron sputtering. The target material for depositing the fourth mixed oxide layer is a fourth mixed oxide target material composed of Al2O3, Dy2O3 and Gd2O3, wherein the mass ratio of Al2O3, Dy2O3 and Gd2O3 in the fourth mixed oxide target material is 100:(1-2):(0.5-1.5).

[0016] In a preferred embodiment, the process parameters for depositing the fourth mixed oxide layer are as follows: the power supply type is an RF power supply, the sputtering power is 60-80W, the sputtering voltage is 40-50V, the argon flow rate is 20-30sccm, and the sputtering temperature is 80-100℃.

[0017] The present invention provides a musical instrument comprising a metal substrate on which the aforementioned composite material is deposited.

[0018] Compared with existing technologies, the present invention has the following advantages: the composite material of the present invention involves sequentially depositing four specific mixed oxide layers on a metal substrate: the first layer comprises Al2O3, La2O3, and Gd2O3; the second layer comprises Al2O3, La2O3, and CeO2; the third layer comprises Al2O3, Gd2O3, and CeO2; and the fourth layer comprises Al2O3, Dy2O3, and Gd2O3. Each layer is deposited using a magnetron sputtering process, with specific component mass ratios and process parameters controlled. The solution of the present invention can significantly improve the toughness and impact resistance of the paint surface. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the membrane structure according to an embodiment of the present invention.

[0020] Figure 2 This is a TEM photograph of an embodiment of the present invention.

[0021] Figure 3 This is a TEM photograph of another embodiment of the present invention. Detailed Implementation

[0022] The specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings, but it should be understood that the scope of protection of the present invention is not limited to the specific embodiments.

[0023] Figure 1This is a schematic diagram of the film structure according to an embodiment of the present invention. As shown in the figure, the composite material of the present invention includes a first mixed oxide layer, a second mixed oxide layer, a third mixed oxide layer, and a fourth mixed oxide layer on a metal substrate.

[0024] In this invention, all mixed oxide targets were procured from Jiangxi Ketai New Materials Co., Ltd., a company that undertakes customized target services. After providing the composition and requirements of each mixed oxide target to the company, it was able to provide targets that met the requirements. Upon receiving the targets, energy dispersive spectroscopy (EDS) experiments were conducted to verify whether the target composition met the requirements of this invention. To enable comparison with existing technologies, unless otherwise indicated, after depositing the composite materials of subsequent embodiments and comparative examples on the metal substrate, the varnish of Example 2 of prior art CN105199511A was coated onto the outermost mixed oxide layer. Unless otherwise indicated, the experimental tests of this invention include bending performance testing (testing according to GB / T 6742), cupping testing (testing according to GB / T 9753), impact resistance testing (testing according to GB / T 1732), and MEK abrasion resistance testing (testing according to ASTM D5402-2006). In this invention, for the sake of comparability of results, unless otherwise indicated, the thickness of each mixed oxide layer was 30 nm, and the metal substrate was 314 stainless steel.

[0025] Example 1

[0026] The composite material includes: a first mixed oxide layer on a metal substrate, wherein the first mixed oxide layer includes Al2O3, La2O3 and Gd2O3;

[0027] A second mixed oxide layer on a first mixed oxide layer, wherein the second mixed oxide layer comprises Al2O3, La2O3 and CeO2;

[0028] A third mixed oxide layer on the second mixed oxide layer, wherein the third mixed oxide layer comprises Al2O3, Gd2O3 and CeO2;

[0029] A fourth mixed oxide layer on top of the third mixed oxide layer, wherein the fourth mixed oxide layer comprises Al2O3, Dy2O3 and Gd2O3.

[0030] The first mixed oxide layer was deposited on the metal substrate by magnetron sputtering. The target for depositing the first mixed oxide layer was composed of Al2O3, La2O3, and Gd2O3, with a mass ratio of 100:2:0.5. The process parameters for depositing the first mixed oxide layer were: RF power supply, sputtering power of 60W, sputtering voltage of 40V, argon flow rate of 20sccm, and sputtering temperature of 80℃.

[0031] The second mixed oxide layer was deposited on the first mixed oxide layer by magnetron sputtering. The target material for depositing the second mixed oxide layer was composed of Al2O3, La2O3, and CeO2, with a mass ratio of 100:0.5:2. The process parameters for depositing the second mixed oxide layer were: RF power supply, sputtering power of 70W, sputtering voltage of 60V, argon flow rate of 20sccm, and sputtering temperature of 80℃.

[0032] The third mixed oxide layer was deposited on the second mixed oxide layer by magnetron sputtering. The target material for depositing the third mixed oxide layer was composed of Al2O3, Gd2O3, and CeO2, with a mass ratio of 100:1.5:2. The process parameters for depositing the third mixed oxide layer were: RF power supply, sputtering power of 70W, sputtering voltage of 60V, argon flow rate of 20sccm, and sputtering temperature of 80℃.

[0033] The fourth mixed oxide layer was deposited on the third mixed oxide layer by magnetron sputtering. The target material for depositing the fourth mixed oxide layer was composed of Al2O3, Dy2O3, and Gd2O3, with a mass ratio of 100:1:0.5. The process parameters for depositing the fourth mixed oxide layer were: RF power supply, sputtering power of 60W, sputtering voltage of 40V, argon flow rate of 20sccm, and sputtering temperature of 80℃. After depositing the composite material of Example 1 on the metal substrate, a portion of the sample was cut by mechanical cutting, and then this portion of the sample was photographed by transmission electron microscopy (TEM) with electron beam irradiation from the fourth mixed oxide layer. See the TEM image of the sample of Example 1. Figure 2 . Figure 2The grain boundaries are marked with solid white lines. The varnish of Example 2 (CN105199511A) was coated over the fourth mixed oxide layer of Example 1. The samples were then subjected to bending performance tests, cupping tests, impact resistance tests, and MEK wiping resistance tests. The bending performance was 1 mm, the cupping performance was 6 mm, the impact resistance was 65 cm, and the MEK wiping resistance was 40 cycles. From a solid-state physics perspective, the microscopic mechanism of these results may be as follows: First, the multilayer oxide structure forms an optimized stress gradient transition with the metal substrate and the varnish layer. In the first mixed oxide layer (Al2O3-La2O3-Gd2O3), La2O3 and Gd2O3, as rare earth oxides, exhibit a controllable mismatch in lattice parameters with the base metal. Through low-temperature deposition at 80°C during magnetron sputtering, high-density nanoscale lattice distortion can be generated at the interface. This distortion not only enhances the chemical bonding strength between the oxide layer and the metal matrix but also creates a dislocation pinning effect, allowing the interface to dissipate energy through dislocation slip rather than crack propagation when subjected to bending stress. When the varnish layer is bent by external force, this underlying layer buffers stress concentration through microscopic plastic deformation, improving the varnish's bending performance. Secondly, the gradient distribution of rare earth elements between layers constructs a discontinuous band structure. Ce in the second layer (Al2O3-La2O3-CeO2) 3+ / Ce 4+ Mixed valence states and Gd in the third layer (Al2O3-Gd2O3-CeO2) 3+ 4f 7 Electronic configuration leads to local density of states reconstruction, generating space charge regions at interlayer interfaces. When subjected to biaxial tensile stress in a cupping test, these space charge regions attract oxygen vacancies to aggregate, forming electric dipoles. These dipoles, through field stretching, partially offset the mechanical stress, thus improving the plastic deformation capacity of the coating system. Simultaneously, the oxygen vacancy migration mechanism of CeO2 can activate the redistribution of lattice oxygen during deformation, promoting local stress relaxation. Third, the altered phonon scattering modes at multilayer interfaces significantly enhance impact resistance. In the fourth layer (Al2O3-Dy2O3-Gd2O3), Dy... 3+ The high magnetic moment (10.6 μB) and Gd 3+The S-state ground state generates spin-phonon coupling, which can convert about 60% of the kinetic energy into lattice vibrational energy and dissipate it through nonradiative transitions upon instantaneous impact. The approximately 5 nm wide compositional transition region between layers acts as a phonon scattering interface, effectively suppressing the cross-layer propagation speed of cracks. Finally, the dense nanocomposite structure and the catalytic passivation effect of rare earth elements jointly enhance the MEK resistance. The continuous Al2O3 phase in each layer forms a pervasive chemical barrier network, while rare earth oxides are segregated at grain boundaries. In particular, La2O3 and Dy2O3 preferentially occupy triple nodes at grain boundaries during sputtering, and their low oxygen ion migration barrier (approximately 0.8 eV) can quickly repair oxygen vacancies caused by solvent erosion. When MEK solvent attempts to penetrate, the redox properties of CeO2 catalyze the decomposition of solvent molecules, while Gd2O3 captures free radicals through 4f electron localization, blocking the solvent degradation pathway within a 50 nm range of the surface layer.

[0034] Example 2

[0035] The composite material includes: a first mixed oxide layer on a metal substrate, wherein the first mixed oxide layer includes Al2O3, La2O3 and Gd2O3;

[0036] A second mixed oxide layer on a first mixed oxide layer, wherein the second mixed oxide layer comprises Al2O3, La2O3 and CeO2;

[0037] A third mixed oxide layer on the second mixed oxide layer, wherein the third mixed oxide layer comprises Al2O3, Gd2O3 and CeO2;

[0038] A fourth mixed oxide layer on top of the third mixed oxide layer, wherein the fourth mixed oxide layer comprises Al2O3, Dy2O3 and Gd2O3.

[0039] The first mixed oxide layer was deposited on a metal substrate by magnetron sputtering. The target for depositing the first mixed oxide layer was composed of Al2O3, La2O3, and Gd2O3, with a mass ratio of 100:3:1. The process parameters for depositing the first mixed oxide layer were: RF power supply, sputtering power of 80W, sputtering voltage of 50V, argon flow rate of 20sccm, and sputtering temperature of 80℃.

[0040] The second mixed oxide layer was deposited on the first mixed oxide layer by magnetron sputtering. The target material for depositing the second mixed oxide layer was composed of Al2O3, La2O3, and CeO2, with a mass ratio of 100:1:3. The process parameters for depositing the second mixed oxide layer were: RF power supply, sputtering power of 90W, sputtering voltage of 70V, argon flow rate of 20sccm, and sputtering temperature of 80℃.

[0041] The third mixed oxide layer was deposited on the second mixed oxide layer by magnetron sputtering. The target material for depositing the third mixed oxide layer was composed of Al2O3, Gd2O3, and CeO2, with a mass ratio of 100:3:3. The process parameters for depositing the third mixed oxide layer were: RF power supply, sputtering power of 90W, sputtering voltage of 70V, argon flow rate of 20sccm, and sputtering temperature of 80℃.

[0042] The fourth mixed oxide layer was deposited on the third mixed oxide layer by magnetron sputtering. The target material for depositing the fourth mixed oxide layer was composed of Al2O3, Dy2O3, and Gd2O3, with a mass ratio of 100:2:1.5. The process parameters for depositing the fourth mixed oxide layer were: RF power supply, sputtering power of 80W, sputtering voltage of 50V, argon flow rate of 20sccm, and sputtering temperature of 80℃. After depositing the composite material of Example 2 on the metal substrate, a portion of the sample was cut by mechanical cutting, and then this portion of the sample was photographed by transmission electron microscopy (TEM) with electron beam irradiation from the fourth mixed oxide layer. See [link to TEM image of the sample from Example 2]. Figure 3 . Figure 3 The grain boundaries are marked with solid white lines. The varnish of Example 2 (CN105199511A) was coated over the fourth mixed oxide layer of Example 2. The samples were then subjected to bending performance tests, cupping tests, impact resistance tests, and MEK wiping resistance tests. The bending performance was 1 mm, the cupping performance was 6 mm, the impact resistance was 65 cm, and the MEK wiping resistance was 38 cycles.

[0043] Example 3

[0044] The composite material includes: a first mixed oxide layer on a metal substrate, wherein the first mixed oxide layer includes Al2O3, La2O3 and Gd2O3;

[0045] A second mixed oxide layer on a first mixed oxide layer, wherein the second mixed oxide layer comprises Al2O3, La2O3 and CeO2;

[0046] A third mixed oxide layer on the second mixed oxide layer, wherein the third mixed oxide layer comprises Al2O3, Gd2O3 and CeO2;

[0047] A fourth mixed oxide layer on top of the third mixed oxide layer, wherein the fourth mixed oxide layer comprises Al2O3, Dy2O3 and Gd2O3.

[0048] The first mixed oxide layer was deposited on the metal substrate by magnetron sputtering. The target for depositing the first mixed oxide layer was composed of Al2O3, La2O3, and Gd2O3, with a mass ratio of 100:2.5:0.8. The process parameters for depositing the first mixed oxide layer were: RF power supply, sputtering power of 70W, sputtering voltage of 45V, argon flow rate of 20sccm, and sputtering temperature of 80℃.

[0049] The second mixed oxide layer was deposited on the first mixed oxide layer by magnetron sputtering. The target material for depositing the second mixed oxide layer was composed of Al2O3, La2O3, and CeO2, with a mass ratio of 100:0.8:2.5. The process parameters for depositing the second mixed oxide layer were: RF power supply, sputtering power of 80W, sputtering voltage of 65V, argon flow rate of 20sccm, and sputtering temperature of 80℃.

[0050] The third mixed oxide layer was deposited on the second mixed oxide layer by magnetron sputtering. The target material for depositing the third mixed oxide layer was composed of Al2O3, Gd2O3, and CeO2, with a mass ratio of 100:2:2.5. The process parameters for depositing the third mixed oxide layer were: RF power supply, sputtering power of 80W, sputtering voltage of 65V, argon flow rate of 20-30 sccm, and sputtering temperature of 80-100℃.

[0051] The fourth mixed oxide layer was deposited on the third mixed oxide layer by magnetron sputtering. The target material for depositing the fourth mixed oxide layer was composed of Al2O3, Dy2O3, and Gd2O3, with a mass ratio of 100:1.5:1. The process parameters for depositing the fourth mixed oxide layer were: RF power supply, sputtering power of 70W, sputtering voltage of 45V, argon flow rate of 20sccm, and sputtering temperature of 80℃. The varnish of Example 2 (CN105199511A) was coated on the fourth mixed oxide layer of Example 3. Subsequently, the sample was subjected to bending performance tests, cupping tests, impact resistance tests, and MEK abrasion resistance tests. The bending performance was 1 mm, the cupping performance was 6.5 mm, the impact resistance was 65 cm, and the MEK abrasion resistance was 42 cycles.

[0052] Comparative Example 1

[0053] A first mixed oxide layer was deposited only on a metal substrate. The target material for depositing the first mixed oxide layer was a mixed oxide target composed of Al2O3, La2O3, and Gd2O3, wherein the mass ratio of Al2O3, La2O3, and Gd2O3 in the first mixed oxide target was 100:2:0.5. The process parameters for depositing the first mixed oxide layer were: RF power supply, sputtering power of 60W, sputtering voltage of 40V, argon flow rate of 20sccm, and sputtering temperature of 80℃. The thickness of the first mixed oxide layer was 120nm. The varnish of Example 2 of CN105199511A was coated on the fourth mixed oxide layer of Comparative Example 1. Subsequently, the sample was subjected to bending performance tests, cupping tests, impact resistance tests, and MEK abrasion resistance tests. The bending performance was 1.5mm, the cupping performance was 4mm, the impact resistance was 55cm, and the MEK abrasion resistance was 30 cycles.

[0054] Comparative Example 2

[0055] The composite material includes: a first mixed oxide layer on a metal substrate, wherein the first mixed oxide layer includes Al2O3 and La2O3;

[0056] A second mixed oxide layer on a first mixed oxide layer, wherein the second mixed oxide layer comprises Al2O3 and CeO2;

[0057] A third mixed oxide layer on the second mixed oxide layer, wherein the third mixed oxide layer comprises Al2O3 and Gd2O3;

[0058] A fourth mixed oxide layer on top of a third mixed oxide layer, wherein the fourth mixed oxide layer consists of Al2O3 and Dy2O3.

[0059] The first mixed oxide layer is deposited on the metal substrate by magnetron sputtering. The target material for depositing the first mixed oxide layer is a first mixed oxide target material composed of Al2O3 and La2O3, wherein the mass ratio of Al2O3 to La2O3 in the first mixed oxide target material is 100:2.

[0060] The second mixed oxide layer is deposited on the first mixed oxide layer by magnetron sputtering. The target material for depositing the second mixed oxide layer is a second mixed oxide target material composed of Al2O3 and CeO2, wherein the mass ratio of Al2O3 to CeO2 in the second mixed oxide target material is 100:2.

[0061] The third mixed oxide layer is deposited on the second mixed oxide layer by magnetron sputtering. The target material for depositing the third mixed oxide layer is a third mixed oxide target material composed of Al2O3 and Gd2O3, wherein the mass ratio of Al2O3 to Gd2O3 in the third mixed oxide target material is 100:1.5.

[0062] The fourth mixed oxide layer was deposited on the third mixed oxide layer by magnetron sputtering. The target material for depositing the fourth mixed oxide layer was a fourth mixed oxide target material composed of Al2O3 and Dy2O3, wherein the mass ratio of Al2O3 to Dy2O3 in the fourth mixed oxide target material was 100:1. The remaining parameters are the same as in Example 1. The varnish of Example 2 (CN105199511A) was coated on the fourth mixed oxide layer of Comparative Example 2. Subsequently, the sample was subjected to bending performance test, cupping test, impact resistance test, and MEK wiping resistance test. The bending performance was 1.5 mm, the cupping performance was 5 mm, the impact resistance was 55 cm, and the MEK wiping resistance was 35 cycles.

[0063] Comparative Example 3

[0064] In the first mixed oxide target, the mass ratio of Al2O3, La2O3, and Gd2O3 was 100:6:6. In the second mixed oxide target, the mass ratio of Al2O3, La2O3, and CeO2 was 100:4:5. The varnish of Example 2 (CN105199511A) was coated over the fourth mixed oxide layer of Comparative Example 3. Subsequently, the sample underwent bending performance testing, cupping testing, impact resistance testing, and MEK wiping resistance testing. The bending performance was 2 mm, the cupping performance was 4 mm, the impact resistance was 55 cm, and the MEK wiping resistance was 32 cycles.

[0065] Comparative Example 4

[0066] The process parameters for depositing the second mixed oxide layer were: RF power supply, sputtering power of 150W, sputtering voltage of 150V, argon flow rate of 20 sccm, and sputtering temperature of 80℃. The process parameters for depositing the fourth mixed oxide layer were: RF power supply, sputtering power of 150W, sputtering voltage of 120V, argon flow rate of 20 sccm, and sputtering temperature of 80℃. Macroscopic cracks appeared on the surface of the composite material, and no further experiments were conducted.

[0067] The above description of specific embodiments of the present invention is intended to be illustrative and exemplary, and is not exhaustive or intended to limit the invention to the specific forms disclosed. Many modifications and variations are possible based on the above teachings. The embodiments were chosen and described in order to best explain the principles of the invention and its practical application, thereby enabling others skilled in the art to best utilize the invention and its various embodiments with various modifications for their intended specific use. The scope of protection of the present invention should be defined by the appended claims and their equivalents.

Claims

1. A composite material for improving the toughness of a paint film, the composite material comprising: a first mixed oxide layer on a metal substrate, wherein the first mixed oxide layer comprises Al2O3, La2O3 and Gd2O3; a second mixed oxide layer on the first mixed oxide layer, wherein the second mixed oxide layer comprises Al2O3, La2O3 and CeO2; a third mixed oxide layer on the second mixed oxide layer, wherein the third mixed oxide layer comprises Al2O3, Gd2O3 and CeO2; a fourth mixed oxide layer on the third mixed oxide layer, wherein the fourth mixed oxide layer comprises Al2O3, Dy2O3 and Gd2O3.

2. The composite material of claim 1, wherein, The first mixed oxide layer is deposited on the metal substrate by magnetron sputtering, and a target material for depositing the first mixed oxide layer is a first mixed oxide target material composed of Al2O3, La2O3 and Gd2O3, wherein the mass ratio of Al2O3, La2O3 and Gd2O3 in the first mixed oxide target material is 100: (2-3) : (0.5-1).

3. The composite material of claim 1, wherein, The process parameters for depositing the first mixed oxide layer are as follows: the power source type is a radio frequency power source, the sputtering power is 60-80 W, the sputtering voltage is 40-50 V, the argon flow rate is 20-30 sccm, and the sputtering temperature is 80-100℃.

4. The composite material of claim 1, wherein, The second mixed oxide layer is deposited on the first mixed oxide layer by magnetron sputtering, and a target material for depositing the second mixed oxide layer is a second mixed oxide target material composed of Al2O3, La2O3 and CeO2, wherein the mass ratio of Al2O3, La2O3 and CeO2 in the second mixed oxide target material is 100: (0.5-1) : (2-3).

5. The composite material of claim 4, wherein, The process parameters for depositing the second mixed oxide layer are as follows: the power source type is a radio frequency power source, the sputtering power is 70-90 W, the sputtering voltage is 60-70 V, the argon flow rate is 20-30 sccm, and the sputtering temperature is 80-100℃.

6. The composite material of claim 1, wherein, The third mixed oxide layer is deposited on the second mixed oxide layer by magnetron sputtering, and a target material for depositing the third mixed oxide layer is a third mixed oxide target material composed of Al2O3, Gd2O3 and CeO2, wherein the mass ratio of Al2O3, Gd2O3 and CeO2 in the third mixed oxide target material is 100: (1.5-3) : (2-3).

7. The composite material of claim 6, wherein, The process parameters for depositing the third mixed oxide layer are as follows: the power source type is a radio frequency power source, the sputtering power is 70-90 W, the sputtering voltage is 60-70 V, the argon flow rate is 20-30 sccm, and the sputtering temperature is 80-100℃.

8. The composite material of claim 1, wherein, The fourth mixed oxide layer is deposited on the third mixed oxide layer by magnetron sputtering, and a target material for depositing the fourth mixed oxide layer is a fourth mixed oxide target material composed of Al2O3, Dy2O3 and Gd2O3, wherein the mass ratio of Al2O3, Dy2O3 and Gd2O3 in the fourth mixed oxide target material is 100: (1-2): (0.5-1.5).

9. The composite material of claim 8, wherein, The process parameters for depositing the fourth mixed oxide layer are as follows: the power source type is a radio frequency power source, the sputtering power is 60-80 W, the sputtering voltage is 40-50 V, the argon flow rate is 20-30 sccm, and the sputtering temperature is 80-100 DEG C.

10. A musical instrument comprising a metal substrate, characterized in that The metal substrate surface is deposited with the composite material as claimed in any one of claims 1-9.

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