High-hardness and high-toughness TiAlCrSiBN multi-element coating

Abstract

The invention discloses a TiAlCrSiBN multi-element coating with high hardness and toughness, and relates to the technical field of surface coatings. The TiAlCrSiBN multi-element coating sequentially comprises an AlCrBN layer, a TiAlCrSiBN layer and a TiAlSiN layer from inside to outside, the three layers are organically combined and have a synergistic effect, the hardness of the outer layer and the middle layer is high, the toughness of the middle layer and the inner layer is good, and therefore the whole coating has the comprehensive mechanical properties of high toughness and high bonding strength, and the service life of the coating is prolonged. The composite material can be used for cutting high-strength difficult-to-machine materials and protecting the surfaces of mechanical parts with high wear-resistant requirements, such as molds under complex working conditions.

Description

Technical Field

[0001] The invention belongs to the technical field of surface coatings, and in particular relates to a high-hardness and toughness TiAlCrSiBN multi-element coating. Background Art

[0002] Depositing a hard coating on the surface of a cutting tool is an important means to improve the wear resistance of the cutting tool surface and extend the tool life. The wear resistance of the tool surface is often achieved by obtaining a hard coating with high hardness. Generally, the higher the coating hardness, the better the wear resistance of the tool surface. TiAlN coating is widely used as a tool coating due to its high hardness and good oxidation resistance. TiAlN coated tools are suitable for cutting a variety of processed materials and working conditions and have strong versatility. However, when facing the cutting of difficult-to-process materials such as high-strength alloy steel and high-temperature alloy, they show insufficient wear resistance. The TiAlSiN coating formed by doping Si has a significant increase in the hardness and wear resistance of the coating due to the change in the microstructure of the coating. The TiAlSiN coated tool exhibits very excellent wear resistance. However, in practical applications, TiAlSiN coated tools often fail early due to the large brittleness of the TiAlSiN coating. Therefore, simply increasing the hardness of the coating does not necessarily increase the actual service life of the coated tool. The toughness of the coating is also a key factor in determining the life of the coated tool.

[0003] Doping with alloying elements is an important method to improve the toughness of TiAlSiN coatings, and it is also one of the research hotspots in the field of coatings in recent years. However, although the toughness of TiAlSiN coatings is improved by doping with alloying elements (such as Cr, Y, etc.), the hardness of the coatings is greatly sacrificed, which is not conducive to wear resistance. Therefore, the development of hard and tough high-wear-resistant TiAlSiN coatings is of great significance to meet the actual production and processing needs of difficult-to-process materials such as high-strength alloy steels and high-temperature alloys. Summary of the invention

[0004] The purpose of the present invention is to provide a high-hardness and toughness TiAlCrSiBN multi-element coating in view of the problems existing in the prior art.

[0005] To achieve this object, the technical solution provided by the present invention is: to provide a high hardness and toughness TiAlCrSiBN multi-layer coating, wherein the TiAlCrSiBN multi-layer coating is composed of three layers, the inner layer connected to the substrate is an AlCrBN layer with a thickness of 0.5~1.5μm; the outermost layer is a TiAlSiN layer with a thickness of 0.5~1.5μm; between the inner layer and the outer layer is a TiAlCrSiBN intermediate layer with a thickness of 0.5~1μm.

[0006] Furthermore, in the AlCrBN inner layer, the atomic percentage of Al element is 20% to 35%, the atomic percentage of Cr element is 10% to 15%, the atomic percentage of B element is 1.5% to 5%, and the atomic percentage of N element is 45% to 55%.

[0007] Furthermore, in the outermost layer of the TiAlSiN, the atomic percentage of the Ti element is 15% to 20%, the atomic percentage of the Al element is 10% to 20%, the atomic percentage of the Si element is 5% to 15%, and the atomic percentage of the N element is 45% to 55%.

[0008] Furthermore, in the TiAlCrSiBN intermediate layer, the atomic percentage of Ti element is 7%-15%, the atomic percentage of Al element is 15%-30%, the atomic percentage of Cr element is 7%-15%, the atomic percentage of Si element is 5%-10%, the atomic percentage of B element is 1%-5%, and the atomic percentage of N element is 40%-60%; the TiAlCrSiBN intermediate layer is microscopically composed of a nanoscale layered structure, and the thickness of each nanoscale layer is 5-15nm.

[0009] Furthermore, the TiAlCrSiBN multi-element coating is obtained by a process selected from arc ion plating and magnetron sputtering, and the substrate on which the TiAlCrSiBN multi-element coating is deposited is selected from the group consisting of TiCN-based cermet, cemented carbide and high alloy steel.

[0010] Compared with the prior art, the beneficial effects of the present invention are as follows: the high hardness and toughness TiAlCrSiBN multi-layer coating provided by the present invention is composed of three layers with different structures and components. The three layers are organically combined and work synergistically to make the coating have both good toughness and high hardness characteristics, thereby obtaining excellent wear resistance. First, the AlCrBN inner layer connected to the substrate softens the coating due to the formation of a small amount of amorphous by the B element in the coating, so that the coating has very excellent toughness and bonding performance. Secondly, the TiAlSiN in the outer layer mainly plays the role of its high hardness. Then, the outermost layer of TiAlSiN and the inner layer of AlCrBN are organically connected through the TiAlCrSiBN layer, and the TiAlCrSiBN middle layer is composed of a nano-scale multilayer structure. Due to the strengthening effect of the interlayer interface, the TiAlCrSiBN middle layer has the characteristics of high hardness and high toughness at the same time. Therefore, the middle layer matches both the inner layer and the outermost layer in terms of performance. In general, the high-hardness and toughness TiAlCrSiBN multi-element coating provided by the present invention achieves both good toughness and high hardness of the coating as a whole through the coordinated design of the coating structure and components. DETAILED DESCRIPTION

[0011] The present invention is further described below by means of specific embodiments, but the protection content of the present invention is not limited to the following embodiments, and any non-creative changes made by those skilled in the art on the basis of the present invention belong to the protection scope of the present invention.

[0012] Example 1

[0013] The TiAlCrSiBN multi-layer coating deposited on the TiCN-based metal ceramic substrate by arc ion plating consists of three layers: the inner layer connected to the substrate is the AlCrBN layer with a thickness of 0.7μm; the outermost layer is the TiAlSiN layer with a thickness of 0.6μm; and the TiAlCrSiBN intermediate layer between the inner and outer layers is 0.6μm thick. The atomic percentage of Al in the AlCrBN sublayer is 30.3%, the atomic percentage of Cr is 14.1%, the atomic percentage of B is 3.6%, and the atomic percentage of N is 52%. The atomic percentage of Ti in the outermost layer of TiAlSiN is 15.3%, the atomic percentage of Al is 18.7%, the atomic percentage of Si is 11.3%, and the atomic percentage of N is 54.7%. The atomic percentage of Ti in the TiAlCrSiBN intermediate layer is 8.5%, the atomic percentage of Al is 22.6%, the atomic percentage of Cr is 8.3%, the atomic percentage of Si is 7.2%, the atomic percentage of B is 2.6%, and the atomic percentage of N is 50.8%. The TiAlCrSiBN intermediate layer is composed of nano-level layered structures, and the thickness of each nano-level layer is 12.9nm. According to the test, the TiAlCrSiBN multi-layer coating has a dense structure and is well bonded to the substrate. The bonding grade is HF1, the hardness is 40.8GPa, and the fracture toughness is 42.7MPa·m 1 / 2 .

[0014] Example 2

[0015] The TiAlCrSiBN multi-layer coating deposited on the TiCN-based metal ceramic substrate by arc ion plating consists of three layers: the inner layer connected to the substrate is the AlCrBN layer with a thickness of 0.8μm; the outermost layer is the TiAlSiN layer with a thickness of 1.2μm; and the TiAlCrSiBN intermediate layer between the inner and outer layers is 0.7μm thick. The atomic percentage of Al in the AlCrBN sublayer is 32.6%, the atomic percentage of Cr is 13.8%, the atomic percentage of B is 2.8%, and the atomic percentage of N is 50.8%. The atomic percentage of Ti in the outermost layer of TiAlSiN is 17.6%, the atomic percentage of Al is 19.1%, the atomic percentage of Si is 10.6%, and the atomic percentage of N is 52.7%. The atomic percentage of Ti in the TiAlCrSiBN intermediate layer is 9.3%, the atomic percentage of Al is 23.2%, the atomic percentage of Cr is 7.6%, the atomic percentage of Si is 6.9%, the atomic percentage of B is 1.9%, and the atomic percentage of N is 51.1%. The TiAlCrSiBN intermediate layer is composed of nano-level layered structures, and the thickness of each nano-level layer is 8.7nm. According to the test, the TiAlCrSiBN multi-layer coating has a dense structure and is well bonded to the substrate. The bonding grade is HF1, the hardness is 44.1GPa, and the fracture toughness is 33.8MPa·m 1 / 2 .

[0016] Example 3

[0017] The TiAlCrSiBN multi-layer coating deposited on the cemented carbide substrate by arc ion plating consists of three layers: the inner layer connected to the substrate is the AlCrBN layer with a thickness of 1.1μm; the outermost layer is the TiAlSiN layer with a thickness of 0.7μm; and the TiAlCrSiBN intermediate layer between the inner and outer layers is 0.9μm thick. The atomic percentage of Al in the AlCrBN sublayer is 29.5%, the atomic percentage of Cr is 15.2%, the atomic percentage of B is 2.9%, and the atomic percentage of N is 52.4%. The atomic percentage of Ti in the outermost layer of TiAlSiN is 17.7%, the atomic percentage of Al is 16.8%, the atomic percentage of Si is 12.6%, and the atomic percentage of N is 52.9%. The atomic percentage of Ti in the TiAlCrSiBN intermediate layer is 9.3%, the atomic percentage of Al is 24.3%, the atomic percentage of Cr is 9.4%, the atomic percentage of Si is 8.3%, the atomic percentage of B is 2.2%, and the atomic percentage of N is 46.5%. The TiAlCrSiBN intermediate layer is composed of nano-level layered structures, and the thickness of each nano-level layer is 10.3nm. According to the test, the TiAlCrSiBN multi-layer coating has a dense structure and is well bonded to the substrate. The bonding grade is HF1, the hardness is 42.6GPa, and the fracture toughness is 37.3MPa·m 1 / 2 .

Claims

1. A high hardness and toughness TiAlCrSiBN multi-element coating, characterized by: The TiAlCrSiBN multi-layer coating is composed of three layers, the inner layer connected to the substrate is an AlCrBN layer with a thickness of 0.5-1.5 μm; The outermost layer is a TiAlSiN layer with a thickness of 0.5~1.5μm; between the inner and outer layers is a TiAlCrSiBN intermediate layer with a thickness of 0.5~1μm.

2. The high hardness and toughness TiAlCrSiBN multi-element coating according to claim 1, characterized in that: The atomic percentage of Al element in the AlCrBN inner layer is 20%-35%, the atomic percentage of Cr element is 10%-15%, the atomic percentage of B element is 1.5%-5%, and the atomic percentage of N element is 45%-55%.

3. The high hardness and toughness TiAlCrSiBN multi-element coating according to claim 1, characterized in that: The atomic percentage of the Ti element in the outermost layer of the TiAlSiN is 15% to 20%, the atomic percentage of the Al element is 10% to 20%, the atomic percentage of the Si element is 5% to 15%, and the atomic percentage of the N element is 45% to 55%.

4. The high hardness and toughness TiAlCrSiBN multi-element coating according to claim 1, characterized in that: The atomic percentage of Ti element in the TiAlCrSiBN intermediate layer is 7%-15%, the atomic percentage of Al element is 15%-30%, the atomic percentage of Cr element is 7%-15%, the atomic percentage of Si element is 5%-10%, the atomic percentage of B element is 1%-5%, and the atomic percentage of N element is 40%-60%; the TiAlCrSiBN intermediate layer is composed of a nano-scale layered structure microscopically, and the thickness of each nano-scale layer is 5-15nm.

5. The high hardness and toughness TiAlCrSiBN multi-element coating according to claim 1, characterized in that: The TiAlCrSiBN multi-element coating is obtained by a process selected from arc ion plating and magnetron sputtering. The substrate on which the TiAlCrSiBN multi-element coating is deposited is selected from the group consisting of TiCN-based cermet, hard alloy and high alloy steel.