PVD (Physical Vapor Deposition) target material and application thereof

Abstract

The invention relates to the technical field of surface coatings, and particularly discloses a PVD (Physical Vapor Deposition) target material and application thereof. The PVD target material is prepared from the following components in percentage by mass: 10 to 30 percent of silicon and the balance of metal, and the metal comprises one or more of chromium, zirconium or titanium. According to the PVD target material, after physical vapor deposition, a composite film composed of metal, silicon, metal nitride, silicon nitride and metal silicide can be formed on the surface of a metal base material, through combination of substances with different particle sizes, it can be guaranteed that the composite film is tightly combined, air can be isolated, and the service life of the composite film is prolonged. According to the PVD target material provided by the invention, a gap caused by a PVD film formed by a single-element target material is avoided, so that a PVD layer formed by the PVD target material provided by the invention can be used for enhancing the surface hardness of a metal base material and ensuring that the PVD layer does not change color after being heated, and the PVD layer is relatively good in non-sticky performance and easy in surface cleaning.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of surface coating, more particularly, it relates to a PVD target and application thereof. BACKGROUND

[0002] At present, stainless steel cookware is widely welcomed due to its good durability and relatively low cost, but ordinary stainless steel cookware is prone to discoloration during use, and the surface convex-concave structure is easy to hide dirt, which is quite inconvenient to clean. In order to make ordinary stainless steel cookware achieve non-stick performance, while effectively solving the problem of discoloration of stainless steel cookware, a layer of polytetrafluoroethylene is usually coated on the surface of the cooking utensil. The polytetrafluoroethylene coating is non-toxic under normal conditions, but it will start to volatilize when the heating temperature of the coating reaches 260℃, and the polytetrafluoroethylene coating will start to decompose when the temperature reaches 350℃, so the use temperature of the stainless steel cookware with polytetrafluoroethylene coating generally cannot exceed 250℃. However, the heating temperature of general cooking utensils such as frying pans often exceeds 260℃, therefore, there is a safety hazard, in addition, the polytetrafluoroethylene coating is not wear-resistant and has the risk of falling off, which is easy to be mistaken for food and affect health. In order to solve the above problems, people gradually apply physical vapor deposition (PVD) technology to form a physical vapor deposition layer on the surface of the metal to the stainless steel cookware. In order to ensure that the stainless steel cookware has non-stick performance, the PVD layer must have a convex-concave structure, however, the existing PVD layer is prone to discoloration at high temperature, and the existing PVD layer with convex-concave structure is prone to hiding dirt, which is not convenient to clean. SUMMARY

[0003] In order to solve the problems of PVD layer discoloration and dirt hiding in the related art, the present application provides a PVD target and application thereof.

[0004] In a first aspect, the present application provides a PVD target, which adopts the following technical solution: A PVD target, composed of 10-30% silicon and the rest of metal, the metal including one or more of chromium, zirconium or titanium, in terms of mass percentage.

[0005] By adopting the above technical solution, the PVD target provided by the present application can form a composite film composed of metal, silicon, metal nitride, silicon nitride and metal silicide on the surface of the metal substrate after physical vapor deposition. The composite film is combined by substances with different particle sizes, which can ensure the tightness of the composite film, isolate air and avoid the gap caused by the single-element target forming the PVD film. Therefore, the PVD layer formed by the PVD target provided by the present application can strengthen the surface hardness of the metal substrate, ensure that the PVD layer does not discolor when heated, has good non-stick performance and the surface is easy to clean.

[0006] Preferably, the PVD target is composed of 15-20% silicon and the balance of chromium by mass percentage.

[0007] The present application can ensure that the PVD target has a low cost while ensuring that the PVD layer formed by the PVD target has good non-stick properties, and can avoid discoloration of the PVD layer due to heat.

[0008] Preferably, the PVD target is composed of 15-20% silicon and the balance of chromium by mass percentage.

[0009] The present application can ensure that the PVD layer formed by the PVD target has a high hardness.

[0010] Preferably, the content of titanium is 0.001-3wt% based on the metal as a whole.

[0011] The present application can control the cost of the PVD target while ensuring that the PVD layer formed by the PVD target has a high hardness, avoid the hardness decrease due to too low titanium content, and also avoid the problem that the cost and hardness do not increase in proportion due to the increase of titanium content.

[0012] Preferably, the PVD target is composed of 15-20% silicon and the balance of chromium by mass percentage.

[0013] The present application can ensure that the PVD layer formed by the PVD target has a high hardness while maintaining the original color of the stainless steel.

[0014] Preferably, the content of titanium is 0.001-3wt% based on the metal as a whole.

[0015] The present application can control the cost of the PVD target while ensuring that the PVD layer formed by the PVD target has a high hardness, avoid the hardness decrease due to too low titanium content, and also avoid the problem that the cost and hardness do not increase in proportion due to the increase of titanium content.

[0016] In a second aspect, the present application provides the use of the PVD target in cookware. In the present application, the cookware is a cooking utensil, preferably including a frying pan, a soup pot, an electric rice cooker liner, an electric pressure cooker liner, an electric fire pot, and a baking tray, etc. heatable cooking utensils.

[0017] Preferably, the PVD target is deposited on the inner metal layer of the cookware by a PVD process to form a PVD coating.

[0018] The present application can ensure that the cookware has high hardness and non-stick performance, is easy to clean, and is not prone to discoloration when heated.

[0019] Preferably, the thickness of the PVD coating is 0.8-3 μm.

[0020] The present application can ensure that the PVD coating does not fall off during use by limiting the thickness of the PVD coating.

[0021] Preferably, the surface roughness Ra of the inner metal layer is greater than or equal to 0.15.

[0022] The present application can ensure that the PVD target is stably deposited on the surface of the inner metal layer during physical vapor deposition without the need for concave-convex structures by limiting the surface roughness of the inner metal layer.

[0023] In summary, the present application has the following advantages: 1. The PVD target provided by the present application is composed of 10-30% silicon and the balance of metal, which includes one or more of chromium, zirconium or titanium. Physical vapor deposition using the PVD target provided by the present application can form a composite film composed of metal, silicon, metal nitride, silicon nitride and metal silicide on the surface of the metal substrate. This composite film, which is composed of substances of different particle sizes, can ensure that the composite film is tightly combined and can isolate air, thereby avoiding gaps that occur when a single-element target is used to form a PVD film. Therefore, the PVD layer formed using the PVD target provided by the present application can strengthen the surface hardness of the metal substrate, ensure that the PVD layer does not discolor when heated, and the PVD layer has good non-stick performance and is easy to clean.

[0024] 2. The PVD target provided by the present application does not need to limit the surface of the metal substrate to be a concave-convex structure, and the surface roughness Ra of the metal layer is preferably greater than or equal to 0.15, which can ensure that the PVD target provided by the present application can be applied to ordinary metal surfaces without the need for concave-convex structures, facilitating the use and promotion of the PVD target. BRIEF DESCRIPTION OF DRAWINGS

[0025] Figure 1 is a photo of the alloy basin with a PVD coating in Example 1 and Comparative Example 2 placed in an environment of 250°C and left for half an hour; Figure 2 is a photo of the alloy basin with a PVD coating in Example 1 and Comparative Example 2 placed in an environment of 300°C and left for half an hour; Figure 3 is a photo of the alloy pot with PVD coating in Example 1 and Comparative Example 2 after being placed in an environment of 350°C for half an hour; Figure 4 is a photo of the alloy pot with PVD coating in Example 1 and Comparative Example 2 after being placed in an environment of 400°C for half an hour; Figure 5 is a photo of the alloy pot with PVD coating in Example 1 after oil immersion and cleaning treatment; Figure 6 is a photo of the alloy pot with PVD coating in Comparative Example 2 after oil immersion and cleaning treatment. DETAILED DESCRIPTION

[0026] The present application is further described in detail below with reference to the accompanying drawings and examples.

[0027] Example 1 An application of a PVD target in cookware, comprising the following steps: Step 1: install an alloy pot with a surface roughness Ra of 0.5 and a PVD target in a deposition chamber so that the distance between them is 50 cm; vacuumize the deposition chamber to 4.5 x 10 -3 Pa, and then gradually heat from 25°C to 355°C in 30 min; then, vacuumize to 2.5 x 10 -3 Pa, and perform a glow discharge plasma surface cleaning treatment in Ar for 25 min at a bias voltage of -800 V, wherein the PVD target is composed of 15% silicon and the balance of chromium by mass percentage; Step 2: perform an etching process for 10 min under an Ar pressure of 2.5 x 10 -3 Pa and a pulsed bias voltage of -600 V (80% duty cycle and 80 kHz frequency); Step 3: reactively prepare a PVD coating in a pure N2 atmosphere: during the deposition process, first introduce N2, adjust the pressure in the deposition chamber to 3.0 x 10 -3 Pa, and at the same time, turn on the magnetron sputtering power to obtain an alloy pot with a PVD coating with a thickness of 1.51 μm.

[0028] Example 2 The difference between Example 2 and Example 1 is that the PVD target in Example 1 is replaced by a PVD target composed of 20% silicon and the balance of chromium by mass percentage.

[0029] Example 3 Example 3 differs from Example 1 in that the "PVD target material consists of 15% silicon and the balance chromium by mass percent" in Example 1 is replaced with "the PVD target material consists of 15% silicon, 82% chromium and 3% titanium by mass percent".

[0030] Example 4 Example 4 differs from Example 1 in that the "PVD target material consists of 15% silicon and the balance chromium by mass percent" in Example 1 is replaced with "the PVD target material consists of 15% silicon, 84.9% chromium and 0.1% titanium by mass percent".

[0031] Example 5 Example 5 differs from Example 1 in that the "PVD target material consists of 15% silicon and the balance chromium by mass percent" in Example 1 is replaced with "the PVD target material consists of 15% silicon, 41% chromium, 41% zirconium and 3% titanium by mass percent".

[0032] Comparative Example 1 Comparative Example 1 differs from Example 1 in that the "PVD target material consists of 15-20% silicon and the balance chromium by mass percent" in Example 1 is replaced with "the PVD target material consists of 15% silicon, 80% chromium and 5% titanium by mass percent".

[0033] Comparative Example 2 Comparative Example 2 differs from Example 1 in that the "PVD target material consists of 15% silicon and the balance chromium by mass percent" in Example 1 is replaced with "the PVD target material is a commercially available PVD target material".

[0034] Performance detection test The alloy pots with PVD coating in Examples 1-5 and Comparative Examples 1-2 were subjected to high temperature treatment, the alloy pots with PVD coating in Examples 1-5 and Comparative Examples 1-2 were respectively placed in an environment of 250°C, 300°C, 350°C and 400°C, and the discoloration was observed after standing for half an hour, the results are shown in Table 1, and, Figures 1-4 The photos of the alloy pots with PVD coating in Example 1 and Comparative Example 2 respectively placed in an environment of 250°C, 300°C, 350°C and 400°C and standing for half an hour, wherein the PVD alloy pot marked is the alloy pot with PVD coating in Example 1.

[0035] Table 1 Discoloration of Examples 1-5 and Comparative Examples 1-2 The alloy pots with PVD coating in Examples 1-5 and Comparative Examples 1-2 were subjected to oil immersion and cleaning treatment, and the cleaning results are shown in Table 2.

[0036] Table 2 Cleaning results of Examples 1-5 and Comparative Examples 1-2 GB / T 4342-1991 "Metal Micro Vickers Hardness Test Method" was used to test the hardness of the alloy pots with PVD coating in Examples 1-5 and Comparative Examples 1-2, and the cleaning results are shown in Table 3, and, Figure 5 The photo of the alloy pot with PVD coating in Example 1 of the present application after oil immersion and cleaning treatment, Figure 6 The photo of the alloy pot with PVD coating in Comparative Example 2 of the present application after oil immersion and cleaning treatment.

[0037] Table 3 Hardness test results of Examples 1-5 and Comparative Examples 1-2 Item Example 1 Example 2 Example 3 Example 4 Example 5 Comparative Example 1 Comparative Example 2 Hardness / HV 1550 1570 1630 1640 1680 1440 1150 The alloy pots with PVD coating in Examples 1-5 and Comparative Examples 1-2 were subjected to non-stick performance test, and the test method was as follows: a proper amount of vegetable oil was poured into the alloy pot, and the non-stick surface was wiped with a soft cloth until it was evenly coated; it was cleaned with warm water above 60°C and a neutral detergent, and then washed with clean water and dried; the cooking utensil was heated on an electric stove with a rated voltage of 220V and an output power of 1kW, and the surface temperature was measured with a surface thermometer with an accuracy of not less than 2.5 grade; when the PVD coating surface temperature reached 150°C-170°C, a fresh egg meeting the requirements of 2nd grade (weight of 50g-60g) of SB / T 10277-1997 was broken and placed in the cooking utensil; when the albumen was basically solidified (during the entire cooking process, the PVD coating surface temperature should not exceed 210°C); the egg was completely taken out with a plastic spatula with a sharp edge thickness of 0.2mm-0.5mm. If there were egg residues attached, they were gently wiped off with a wet sponge or gauze; steps c) and d) were repeated for a total of 3 times, and the results are shown in Table 4.

[0038] Table 4 Non-stick performance test results of Examples 1-5 and Comparative Examples 1-2 Item Example 1 Example 2 Example 3 Example 4 Example 5 Comparative Example 1 Comparative Example 2 Non-stick effect Class I Class I Class I Class I Class I Class I Class II Examples 1-5 and Comparative Examples 1-2 in combination with Tables 1-4 and Figures 1-6It can be seen that the application of the PVD target provided by the present application in the cookware can enhance the surface hardness of the metal base material, the hardness of the PVD coating provided by the present application is more than 8 times that of ordinary steel material, and the PVD target provided by the present application can ensure that the PVD layer does not change color when heated, the PVD layer has good non-stick performance, the surface is easy to clean, and no obvious oil stain is left after cleaning. Moreover, by limiting the content of titanium, the problem that the increase of the content of titanium does not proportionally increase the cost and hardness can be avoided.

[0039] Example 6 The difference between Example 6 and Example 1 is that the "thickness of 1.51 μm" in Example 1 is replaced by "thickness of 2.4 μm".

[0040] Comparative Example 3 The difference between Comparative Example 3 and Comparative Example 2 is that the "surface roughness Ra of 0.5" in Comparative Example 2 is replaced by "surface roughness Ra of 0.16".

[0041] The hardness of the alloy pot with PVD coating in Example 6 and Comparative Example 3 was tested according to GB / T4342-1991 "Metal Micro Vickers Hardness Test Method", and the hardness test results are shown in Table 5.

[0042] Table 5 Hardness test results of Example 1 and 6 and Comparative Example 3 Item Example 1 Example 6 Comparative Example 3 Hardness / HV 1550 1555 1540 The non-stick performance of the alloy pot with PVD coating in Example 1 and 6 and Comparative Example 3 was tested, and the test method was as follows: a proper amount of vegetable oil was poured into the alloy pot, and the non-stick surface was wiped with a soft cloth until it was evenly coated; it was washed with warm water above 60°C with a neutral detergent, then washed with clean water and dried; the cooking appliance was heated on an electric stove with a rated voltage of 220V and an output power of 1kW, the surface temperature was measured with a surface thermometer with an accuracy of not less than 2.5 levels, when the PVD coating surface temperature reached 150°C-170°C, a fresh egg meeting the requirements of 2 levels (weight of 50g-60g) of SB / T 10277-1997 was broken and placed in the cooking appliance, and the albumen was basically coagulated (during the whole cooking process, the PVD coating surface temperature should not exceed 210°C); the egg was completely taken out with a plastic shovel with a sharp edge thickness of 0.2mm-0.5mm. If there was egg residue attached, it was gently wiped off with a wet sponge or gauze; steps c) and d) were repeated for a total of 3 times, and the results were observed and shown in Table 6.

[0043] Table 6 Non-stick performance test results of Example 1 and 6 and Comparative Example 3 It can be seen from the combination of embodiments 1 and 6 and comparative example 3 and in combination with Tables 5-6 that the PVD target provided in the present application can form a PVD coating with good hardness and non-stick performance on metal surfaces with different surface roughness, and the thickness of the PVD coating formed by deposition does not affect the hardness and non-stick performance, while the commercially available PVD target cannot form a PVD coating with non-stick performance on the metal surface. This is because the existing PVD target can only ensure the overall non-stick performance through the original concave-convex structure of the substrate after forming a PVD coating. When the surface of the substrate does not have a concave-convex structure, the PVD coating formed by the existing PVD target cannot make the overall non-stick performance. The PVD target provided in the present application does not require the surface of the substrate to have a concave-convex structure, and can form a PVD coating with a dense structure on a smooth metal surface to ensure non-stick performance.

[0044] The specific embodiments are merely illustrative of the present application, and are not a limitation of the present application. Those skilled in the art can make modifications to the embodiments without creative contribution after reading the present specification, as long as the modifications are within the scope of the claims of the present application.

Claims

1. A PVD target material, characterized in that, The PVD target consists of 10-30% silicon and the balance of metal, by mass percent, the metal including one or more of chromium, zirconium or titanium.

2. The PVD target according to claim 1, characterized in that The PVD target consists of 15-20% silicon and the balance of chromium, by mass percent.

3. The PVD target according to claim 1, wherein The PVD target consists of 15-20% silicon and the balance of metal, by mass percent, the metal being chromium and titanium.

4. The PVD target according to claim 3, wherein The titanium content is 0.001-3wt% based on the metal as a whole.

5. The PVD target according to claim 1, wherein The PVD target consists of 15-20% silicon and the balance of metal, by mass percent, the metal being chromium, zirconium and titanium.

6. The PVD target according to claim 5, wherein The titanium content is 0.001-3wt% based on the metal as a whole.

7. Use of the PVD target of any one of claims 1-6 in cookware.

8. Use according to claim 7, characterized in that, The PVD target is deposited on an inner metal layer of the cookware by a PVD process to form a PVD coating.

9. Use according to claim 8, characterized in that, The PVD coating has a thickness of 0.8-3μm.

10. Use according to claim 8, characterized in that, The inner metal layer has a surface roughness Ra≥0.15.

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