WO2022022705A1

WO2022022705A1 - Tool having hfb2 coating, and manufacturing method therefor

Info

Publication number: WO2022022705A1
Application number: PCT/CN2021/109786
Authority: WO
Inventors: 王成勇; 林海生
Original assignee: 广东工业大学
Priority date: 2020-07-31
Filing date: 2021-07-30
Publication date: 2022-02-03
Also published as: CN112063983B; CN112063983A

Abstract

The present invention discloses a tool having a HfB₂ coating, comprising: a base body; and a HfB₂ coating deposited on the base body by means of DC magnetron sputtering or high-power magnetron sputtering, or HfB₂ coatings and MeN coatings alternately deposited on the base body by means of DC magnetron sputtering or high-power magnetron sputtering, Me being an alloying element. According to the present invention, a single HfB₂ coating or multiple coatings comprising a HfB₂ coating is deposited on the base body of the tool by means of a DC magnetron or high-power magnetron sputtering process; the tool having a HfB₂ coating has excellent comprehensive properties such as high hardness and high thermal conductivity; during machining of difficult-to-machine materials such as titanium alloys and high-temperature alloys, local high temperature in the cutting area can be effectively reduced, adhesive wear of the front and rear surfaces of the tool can be inhibited, the wear resistance of the tool is improved, and high-efficiency and high-quality cutting is achieved.

Description

A with HfB 2 Coated cutting tools and methods of making the same

technical field

The invention relates to the technical field of cutting tools, in particular to a cutting tool with HfB ₂ coating and a preparation method thereof. The cutting tool is particularly suitable for high-speed cutting of difficult-to-machine materials.

Background technique

For the tools used for high-speed cutting of difficult-to-machine materials, physical vapor deposition and chemical vapor deposition are usually used to coat the surface of the cutting tool, which can effectively improve the tool life and workpiece machining quality. With the advancement of high-speed machining technology, the performance requirements for coated tools are also getting higher and higher. Tool coating materials are developed from binary coatings such as TiN, TiC, and CrN to multi-component coatings such as TiAlN, TiCN, TiSiN, and TiAlSiN. The coating structure has developed from a single-layer coating to a multi-layer, nano-composite and other structures. The performance of the tool coating in terms of wear resistance, red hardness, oxidation resistance, crack propagation resistance, etc. has been improved to a certain extent. It is also becoming more and more obvious. On the other hand, in recent years, the concept of material "plainization" has also been proposed, that is, the material properties can be enhanced without changing and increasing the material composition; relevant scholars have also adopted the concept of material "plainization" in tool coating. , for the design and preparation of the coating.

With the development of the application of various high-temperature alloys, titanium alloys and other difficult-to-machine materials in various fields, not only high hardness and wear resistance of coated tools are required, but also high thermal conductivity and low Material affinity and other properties to reduce local high temperature in the cutting area during processing, reduce tool bond wear, and improve tool machining life and machining quality. However, the existing coated tools for processing such difficult-to-machine materials have not been able to meet the needs of high-efficiency and high-quality processing.

SUMMARY OF THE INVENTION

The purpose of the present invention is to overcome the hardness, wear resistance, thermal conductivity and affinity to the processing material of the cutting tool in the prior art when the coated tool is used for machining difficult-to-machine materials such as superalloys and titanium alloys. Can not meet the defects of use requirements, provide a tool with higher hardness, wear resistance, thermal conductivity and lower material affinity, the tool reduces the local high temperature in the cutting area during the process of machining difficult-to-machine materials, Reduce tool bond wear and improve tool life and machining quality.

To achieve the above object, the present invention adopts the following technical solutions:

A tool with HfB ₂ coating, comprising:

matrix;

HfB coating deposited _on the substrate using DC magnetron sputtering or high power magnetron sputtering; alternatively, alternating deposition of HfB _on the substrate using DC magnetron sputtering or high power magnetron sputtering Coating and MeN coating, Me stands for alloying element.

The existing coated tools have the defects that the hardness, wear resistance, thermal conductivity and affinity for the processed materials cannot meet the requirements of use when machining high-temperature alloys, titanium alloys and other difficult-to-machine materials. The invention is to deposit HfB ₂ coating on the substrate in the tool. The HfB ₂ coating has excellent comprehensive properties such as high thermal conductivity and high hardness, and has great potential as a tool coating material. Moreover, in the present invention, DC magnetron sputtering or high-power magnetron sputtering is used to prepare HfB ₂ coating, which is suitable for preparing coated tools for industrial applications, giving full play to the excellent performance of HfB ₂ coating, compared with chemical The HfB ₂ coating prepared by vapor deposition technology is more environmentally friendly, and the deposition rate is higher than that of RF magnetron sputtering technology. In the present invention, the HfB ₂ coating is deposited on the base of the tool, which may be a single layer of HfB ₂ coating deposited on the base; or a multi-layer coating of HfB ₂ coating and MeN coating deposited on the base, wherein , Me stands for alloying elements, and HfB coatings and MeN coatings are alternately deposited _on the substrate.

Further, the HfB ₂ coating comprises 20-45% Hf and 55-80% B in atomic percent.

Further, the thickness of the HfB ₂ coating is 0.5-5 μm; or, the total thickness of the HfB ₂ coating and the MeN coating is 0.5-5 μm.

Further, the ratio of the thickness of the HfB ₂ coating to the MeN coating is 1:(0.1-10).

Further, the MeN coating includes 35-65% Me and 35-65% N in atomic percent.

Further, the MeN coating is TiN coating, TiSiN coating, TiAlN coating, AlTiN coating, CrN coating, CrSiN coating or CrAlN coating, and the substrate is a cemented carbide substrate or a high-speed steel substrate.

The present invention also discloses the preparation method of the cutter with _HfB coating, the preparation method adopts coating equipment to deposit the coating on the substrate, and the preparation method comprises the following steps:

Substrate processing step: the substrate is cleaned in ultrasonic waves and heated to remove surface moisture, then the substrate is clamped on a three-dimensional rotatable turntable and sent to the chamber of the coating equipment;

Steps of vacuuming the chamber: firstly vacuum the chamber to below 2×10 ^-3 Pa, and then start the heater to remove the volatile impurities on the surface of the chamber and the substrate;

Glow cleaning step: Pour high-purity gas Ar into the chamber, the vacuum degree in the chamber is 0.05～1.2Pa, set the substrate bias voltage -100～-500V, and perform glow cleaning on the substrate for 10～30min;

Coating preparation steps: set the vacuum degree in the chamber to 0.2～1.5Pa, the substrate bias voltage to 0～-250V, the heating temperature of the heater to be 300～600℃, the rotation speed of the turret to be 1～15rpm, turn on the target power supply, Use DC magnetron sputtering or high-power magnetron sputtering to deposit on the substrate for 40-350min;

Steps for taking out the tool: Turn off the power of the target material, wait until the chamber temperature drops below 100 °C, open the chamber, and take out the tool with HfB ₂ coating.

Further, in the coating preparation step, when a single-layer HfB ₂ coating is deposited on the substrate, the target is HfB ₂ , the gas introduced is Ar, and the target power is 1-7KW.

Further, in the coating preparation step, when the HfB ₂ coating and the MeN coating are alternately deposited on the substrate, the target materials are HfB ₂ and Me targets, and the HfB ₂ coating and MeN are prepared by alternately turning on the HfB ₂ and Me targets. Coating; when the HfB ₂ target is turned on, the gas is Ar, and the target power is 1-7KW; when the Me target is introduced, the gas Ar and N ₂ are introduced, and the flow ratio of Ar:N ₂ is (0.5-3):1, The target power is 1 to 7KW.

Further, when high-power magnetron sputtering is used, the target power source pulse on time is 5-300us, and the pulse-off time is 500-10000us.

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

In the present invention, a DC magnetron or high-power magnetron sputtering process is used to deposit a single-layer HfB ₂ coating or a multi-layer coating comprising the HfB ₂ coating on the base of the tool, and the tool with the HfB ₂ coating has high hardness, Excellent comprehensive properties such as high thermal conductivity can effectively reduce the local high temperature in the cutting area, inhibit the bonding wear of the front and rear rake faces of the tool, improve the wear resistance of the tool, and achieve high efficiency in the processing of difficult-to-machine materials such as titanium alloys and high-temperature alloys. High quality machining.

Description of drawings

₁ is a schematic structural diagram of a tool with HfB coating according to an embodiment of the present invention;

₂ is a schematic structural diagram of a tool with HfB coating according to another embodiment of the present invention;

₃ is a schematic structural diagram of a tool with HfB coating according to another embodiment of the present invention;

Fig. ₄ is the scanning electron microscope picture of the coating section of the tool with HfB coating according to the first embodiment of the present invention;

Fig. 5 is the transmission electron microscope picture of the tool with HfB coating of the _second embodiment of the present invention;

Fig. 6 is the nanoindentation test result diagram of the coating surface of the tool with HfB coating according to the third embodiment of the present invention _;

FIG. 7 is a graph showing the result of scratch testing on the coating surface of the tool with HfB ₂ coating according to Example 4 of the present invention.

detailed description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art without creative work, all belong to the protection scope of the present invention.

Example 1

Please refer to FIG. 1 , which shows a schematic structural diagram of an embodiment of a tool with HfB ₂ coating of the present invention. The tool with HfB ₂ coating shown in FIG. 1 has a single layer of HfB ₂ coating, and the specific structure is: the tool includes a base body 10 and the HfB ₂ coating 20 deposited on the surface of the base body 10 . The HfB ₂ coating 20 is deposited by DC magnetron sputtering. The base body 10 may be a cemented carbide base body. The HfB ₂ coating layer 20 includes, in atomic percent, 41 atomic percent Hf, and 59 atomic percent B; the HfB ₂ coating thickness is 2.5 μm.

_The preparation method of the tool with HfB coating of this embodiment comprises the following steps:

1) Substrate pretreatment: the substrate is cleaned in ultrasonic waves and heated to remove surface moisture, and then the substrate is clamped on a three-dimensional rotatable turntable and sent to the chamber of the coating equipment.

2) Evacuation of the chamber: firstly evacuate the chamber to below 2×10 ^-3 Pa, then turn on the heater and set it to 600℃ for 60min, fully remove the volatile impurities on the surface of the chamber and the substrate, and finally keep the chamber evacuated Degree is below 2×10 ^-3 Pa.

3) Glow cleaning: high-purity gas Ar was introduced, the vacuum degree in the chamber was 1.0Pa, the substrate bias was set to -300V, and the substrate was subjected to glow cleaning for 30min.

4) Preparation of coating: set the vacuum degree in the chamber to 1.0Pa, the substrate bias voltage to -200V, the heating temperature of the heater to be 600°C, the rotation speed of the turntable to be 5rpm, the target material to be HfB ₂ , the gas to be introduced to be Ar, The target power is 6KW, the target power is turned on, and the DC magnetron sputtering technology is used to prepare the coating for 150 minutes;

5) After the coating is completed, turn off the power of the target material, and when the temperature of the chamber drops below 100°C, open the chamber and take out the tool with HfB ₂ coating.

After testing, the prepared tool with HfB ₂ coating has the following properties: the average grain size is 20nm, the coating hardness is 32GPa, the elastic modulus is 520GPa, and the bonding force between the coating and the substrate is 79N.

The coating section of the tool with HfB ₂ coating of this embodiment is scanned by electron microscope, and the obtained scanning electron microscope image is shown in FIG. 4 .

Example 2

Please refer to FIG. 1 , a tool with HfB ₂ coating, the tool has a single layer of HfB ₂ coating, and the specific structure is: the tool includes a substrate 10 and the HfB ₂ coating deposited on the surface of the substrate 10 . 20. The HfB ₂ coating 20 is deposited by high-power magnetron sputtering. The base body 10 is a high-speed steel base body. The HfB ₂ coating layer 20 includes, in atomic percent, 28 atomic percent of Hf, and 72 atomic percent of B; the HfB ₂ coating thickness is 2.8 μm.

2) Evacuation of the chamber: firstly evacuate the chamber to below 2×10 ^-3 Pa, then turn on the heater and set it to 500℃ for 50min, fully remove the volatile impurities on the surface of the chamber and the substrate, and finally keep the chamber evacuated Degree is below 2×10 ^-3 Pa.

3) Glow cleaning: high-purity gas Ar was introduced, the vacuum degree in the chamber was 1.2Pa, the substrate bias was set to -400V, and the substrate was glow cleaned for 20min.

4) Preparation of coating: set the vacuum degree in the chamber to 0.5Pa, the substrate bias voltage to -50V, the heating temperature of the heater to be 400°C, the rotation speed of the turntable to be 8rpm, the target material to be HfB ₂ , the gas to be introduced to be Ar, Using high-power magnetron sputtering technology, the target power is 5KW, the target power pulse on time is 40us, and the pulse off time is 1000us for 350min coating preparation;

After testing, the prepared tool with HfB ₂ coating has the following properties: the average grain size is 10nm, the coating hardness is 48GPa, the elastic modulus is 605GPa, and the bonding force between the coating and the substrate is 82N.

Referring to FIG. 5 , FIG. 5 shows the image observed under the transmission electron microscope of the tool with HfB ₂ coating prepared in this embodiment.

Example three

Please refer to FIG. 2 , a tool with HfB ₂ coating, the tool has a multi-layer coating, and the multi-layer coating includes the HfB ₂ coating. The specific structure of the cutting tool is as follows: the cutting tool includes a base body 10, a first MeN coating 31 deposited on the surface of the base body 10, a HfB ₂ coating 20 deposited on the first MeN coating 31, a coating layer 20 deposited on the surface of the base body 10, Second MeN coating 32 on the HfB coating ₂₀ . Among them, Me represents an alloying element. The first MeN coating 31 , the HfB ₂ coating 20 and the second MeN coating 32 are all deposited by DC magnetron sputtering. The substrate 10 is a cemented carbide substrate, and the first MeN coating 31 and the second MeN coating 32 are both CrAlN coatings.

The HfB ₂ coating 20 comprises, in atomic percent, 38 atomic percent Hf and 62 atomic percent B.

The first MeN coating 31 includes, in atomic percent, Cr at 45 atomic percent and N at 55 atomic percent.

The second MeN coating 32 includes, in atomic percent, Cr at 45 atomic percent and N at 55 atomic percent.

The thickness of the first MeN coating 31 is 1.4 μm, the thickness of the second MeN coating 32 is 1.4 μm, and the thickness of the HfB ₂ coating 20 is 0.7 μm.

2) Evacuation of the chamber: firstly evacuate the chamber to below 2×10 ^-3 Pa, then turn on the heater and set it to 300℃ for 30min, fully remove the volatile impurities on the surface of the chamber and the substrate, and finally keep the chamber evacuated Degree is below 2×10 ^-3 Pa.

3) Glow cleaning: high-purity gas Ar was introduced, the vacuum degree in the chamber was 0.5Pa, the substrate bias was set to -500V, and the substrate was subjected to glow cleaning for 10 minutes.

4) Preparation of coating: set the vacuum degree in the chamber to 0.9Pa, the substrate bias voltage to -150V, the heating temperature of the heater to be 300°C, the rotation speed of the turntable to be 3rpm, and the target materials to be HfB ₂ and Cr targets. HfB ₂ and Cr targets are used to prepare HfB ₂ coating and CrN coating. When the HfB2 target is turned on, the gas is Ar, and the target power is 6KW; when the Cr target is turned on, the gas Ar and N2 are fed, and the flow ratio Ar:N is 1: 1. The target power is 5KW, and the coating is prepared for 350min;

After testing, the prepared tool with HfB ₂ coating has the following properties: the average grain size is 12nm, the bonding force between the coating and the substrate is 90N, the coating hardness is 24GPa, and the elastic modulus is 383GPa

FIG. 6 shows the test results of using a nano-indentation tester to detect the tool with HfB coating of this embodiment. From FIG. ₆ , the load during the process of indenting and lifting from the coating surface with the nano-diamond indenter can be obtained. Displacement curve relationship, thereby deriving the coating hardness and elastic modulus values from the nanoindentation tester.

Example 4

Please refer to FIG. 3 , a tool with HfB ₂ coating, the tool has a multi-layer coating, and the multi-layer coating includes the HfB ₂ coating. The specific structure of the cutting tool is as follows: the cutting tool includes a base body 10, a first HfB ₂ coating 21 deposited on the surface of the base body, a MeN coating 30 deposited on the first HfB ₂ coating 21, a deposit Second HfB ₂ coating 22 on the MeN coating 30 . Among them, Me represents an alloying element. The first HfB ₂ coating 21 , the MeN coating 30 and the second HfB ₂ coating 22 are all deposited by high-power magnetron sputtering. The substrate 10 is a high-speed steel substrate, and the MeN coating 30 is an AlTiN coating.

The first HfB ₂ coating 21 includes, in atomic percent, 22 atomic percent Hf and 78 atomic percent B.

The second HfB ₂ coating 22 includes, in atomic percent, 22 atomic percent Hf and 78 atomic percent B.

The MeN coating 30 includes, in atomic percent, 60 atomic percent AlTi and 40 atomic percent N. Among them, AlTi atomic ratio Al:Ti=65:35.

The thickness of the first HfB ₂ coating 21 is 0.7 μm, the thickness of the second HfB ₂ coating 22 is 0.7 μm, and the thickness of the MeN coating 30 is 0.35 μm.

3) Glow cleaning: high-purity gas Ar was introduced, the vacuum degree in the chamber was 1.2Pa, the substrate bias was set to -500V, and the substrate was subjected to glow cleaning for 30min.

4) Preparation of coating: set the vacuum degree in the chamber to 0.5Pa, the substrate bias voltage to -100V, the heating temperature of the heater to be 550°C, the rotation speed of the turntable to be 3rpm, and the target materials to be HfB ₂ and AlTi targets. HfB ₂ and AlTi targets were used to prepare HfB ₂ coating and AlTiN coating. When the HfB ₂ target was turned on, the gas was Ar, the target power was 5KW, the target power pulse on time was 20us, and the pulse off time was 1200us; when the AlTi target was turned on, the Enter the gas Ar and N ₂ , the flow ratio Ar:N is 1:2, the target power is 5KW, the target power pulse on time is 20us, the pulse off time is 1200us, and the coating preparation is carried out for 280min;

After testing, the prepared tool with HfB ₂ coating has the following properties: the average grain size is 7nm, the hardness of the coating is 42GPa, the elastic modulus is 580GPa, and the bonding force between the coating and the substrate is 85N.

Fig. 7 shows the result of scratch test on the surface of the tool with HfB ₂ coating of this embodiment. It can be seen from Fig. 7 that the coating has no obvious peeling phenomenon between the indenter loading force of 0-85N.

The above are only the preferred embodiments of the present invention, but the present invention should not be limited to the contents disclosed in the embodiments and the accompanying drawings, so any equivalents or modifications accomplished without departing from the spirit disclosed in the present invention are all fall within the protection scope of the present invention.

Claims

A tool with HfB coating, characterized by comprising:

matrix;

HfB coating deposited on the substrate by DC magnetron sputtering or high-power magnetron sputtering ; alternatively, alternately depositing HfB coating on the substrate by DC magnetron sputtering or high-power magnetron sputtering layer and MeN coating, Me stands for alloying element.
The tool with HfB 2 coating according to claim 1, wherein the HfB 2 coating comprises 20-45% Hf and 55-80% B in atomic percentage.
The tool with HfB 2 coating according to claim 1, characterized in that: the thickness of the HfB 2 coating is 0.5-5 μm; or, the total thickness of the HfB 2 coating and the MeN coating is 0.5-5 μm.
The tool with HfB 2 coating according to claim 3, characterized in that: the ratio of the thickness of the HfB 2 coating and the MeN coating is 1:(0.1-10).
The tool with HfB 2 coating according to claim 1, wherein the MeN coating comprises 35-65% Me and 35-65% N in atomic percentage.
The tool with HfB coating according to claim 1 , characterized in that: the MeN coating is TiN coating, TiSiN coating, TiAlN coating, AlTiN coating, CrN coating, CrSiN coating or CrAlN coating coating, the substrate is a cemented carbide substrate or a high-speed steel substrate.
A kind of preparation method of the cutter with HfB coating according to any one of claims 1 to 6, it is characterized in that, adopting coating equipment to deposit coating on the substrate, comprising the following steps:

Substrate processing step: the substrate is cleaned in ultrasonic waves and heated to remove surface moisture, then the substrate is clamped on a three-dimensional rotatable turntable and sent to the chamber of the coating equipment;

Steps of vacuuming the chamber: firstly vacuum the chamber to below 2×10 -3 Pa, and then start the heater to remove the volatile impurities on the surface of the chamber and the substrate;

Glow cleaning step: Pour high-purity gas Ar into the chamber, the vacuum degree in the chamber is 0.05～1.2Pa, set the substrate bias voltage -100～-500V, and perform glow cleaning on the substrate for 10～30min;

Coating preparation steps: set the vacuum degree in the chamber to 0.2~1.5Pa, the substrate bias voltage to 0~-250V, the heating temperature of the heater to be 300~600℃, the rotation speed of the turntable to be 1~15rpm, turn on the target power supply, Use DC magnetron sputtering or high-power magnetron sputtering to deposit on the substrate for 40-350min;

Steps for taking out the tool: Turn off the power of the target material, wait until the chamber temperature drops below 100 °C, open the chamber, and take out the tool with HfB 2 coating.
The preparation method according to claim 7, characterized in that: in the coating preparation step, when a single-layer HfB 2 coating is deposited on the substrate, the target is HfB 2 , the gas introduced is Ar, and the target power is 1～7KW.
The preparation method according to claim 7, characterized in that: in the coating preparation step, when HfB coating and MeN coating are alternately deposited on the substrate, the target materials are HfB and Me targets, and HfB is turned on alternately by turning on the HfB coating alternately. 2 and Me target to prepare HfB 2 coating and MeN coating; when the HfB 2 target is turned on, the gas is Ar, and the target power is 1-7KW; when the Me target is passed, the gas Ar and N 2 , Ar:N 2 The flow ratio is (0.5~3):1, and the target power is 1~7KW.
The preparation method according to claim 7, characterized in that: when high-power magnetron sputtering is used, the pulse on time of the target power supply is 5-300us, and the pulse-off time is 500-10000us.