Alloy, alloy powder, and alloy-coated body having antibacterial activity

Abstract

An alloy composition according to one aspect of the present invention is an alloy composition having antibacterial activity, and may include a first component consisting of Fe and Ni, a second component consisting of at least one selected from the group consisting of Cr, Co, Mo, and Cu, and a third component consisting of at least one selected from the group consisting of Si, B, and P.

Description

Technical Field

[0001] The present invention relates to an alloy, an alloy powder, and an alloy coated body, and more particularly, to an alloy, an alloy powder, and an alloy coated body having an antibacterial or bactericidal effect.

Background Art

[0002] Recently, in the situation of the worldwide pandemic of coronavirus (COVID-19), the worldwide interest and demand for disinfection and sterilization have increased rapidly. In addition to masks and hand disinfectants, antibacterial films are provided on elevator buttons and the like that are contacted by various people in daily life. However, it is realistically impossible to equip this in many fields that require functions such as antibacterial, and the uncertain persistence of antibacterial activity and high cost have become obstacles in the commercialization of antibacterial materials.

[0003] Generally, silver and copper are well-known metals having an antibacterial effect. Copper or an alloy containing these can kill human pathogens including bacteria such as Listeria monocytogenes, salmonella, and methicillin-resistant Staphylococcus aureus (MRSA).

[0004] The US Environmental Protection Agency has declared that alloys containing 65% or more of copper have inherent antibacterial activity. Despite such excellent antibacterial properties, silver and copper are not widely used as general living materials. In particular, although copper is relatively inexpensive compared to silver, the fact is that it is difficult to find its application examples.

[0005] The reasons why it is difficult to commercialize copper include, in addition to price issues, that it is prone to discoloration due to moisture and salt from parts that come into contact with air, moisture, and the human body, resulting in a color difference from non-discolored parts.

[0006] In the case of alloy materials containing copper, the discoloration phenomenon occurs due to the progress of oxidation (dissolution) of alloying elements that impart hue, and in addition to this, it can occur due to the formation of metal oxides on the surface of the metal.

[0007] As metal materials for daily life, generally, alloys in which each metal is appropriately mixed are preferred over pure metals. Conventionally known stainless steels, aluminum alloys, titanium alloys, etc., which are excellent in resistance to discoloration and corrosion, are widely used as typical daily life materials.

[0008] Recently, materials have been proposed in which a surface coating is used to impart an antibacterial effect to stainless steel with excellent corrosion resistance. For example, antibacterial stainless steel plates, painted steel plates, etc. in which silver (Ag) or copper (Cu) is coated on metal using physical vapor deposition (PVD) or chemical vapor deposition (CVD) have been proposed.

[0009] However, the processes of PVD and CVD require a very long time to form the plating layer, resulting in a decrease in economic efficiency, and there are restrictions on the shape of parts due to the size of the vacuum chamber. In addition, such materials have a very thin antibacterial layer and low mechanical properties. Therefore, when loss of the coating layer due to external force occurs, the antibacterial effect cannot be expected in the loss area, and there is a problem that the antibacterial property cannot be permanently maintained.

[0010] Among copper alloy materials, when the Ni content in the Cu-Ni system is 35% or more, the discoloration resistance is improved, but it is impossible to achieve various colors, the raw material price is too high, and there are limitations in using it as a living material. In addition, Ni may cause an allergic reaction in the human body and there is a possibility of heavy metal elution problems, so the development of an alloy that can replace the Cu-Ni alloy is required.

Prior Art Documents

Patent Documents

[0011]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0012] One aspect of the present invention relates to an alloy, alloy powder, and alloy coating body having antibacterial activity, and an object thereof is to provide an efficient alloy, alloy powder, and alloy coating body having excellent antibacterial activity while restricting the addition of expensive metals such as silver and copper.

[0013] One aspect of the present invention is excellent in oxidation resistance, corrosion resistance, and wear resistance characteristics, and an object thereof is to provide an antibacterial material having a long-lasting antibacterial effect and a long lifespan when applied to daily life or industrial products.

[0014] One aspect of the present invention aims to provide an alloy, an alloy powder utilizing the same, and an alloy coating body that are excellent in hardness and can be variously utilized for home appliances, filters, handles in hospitals and public places, daily necessities, etc. according to the processing method.

[0015] One aspect of the present invention aims to provide an alloy coating body including an alloy coating layer that has a metal series color, has less rejection for general users, and can be applied to various forms of base materials.

Means for Solving the Problem

[0016] An alloy according to one aspect of the present invention comprises a first component consisting of Fe and Ni, a second component consisting of at least one or more selected from the group consisting of Cr, Co, Mo, and Cu, and a third component consisting of at least one or more selected from the group consisting of Si, B, and P, wherein, based on 100 parts by weight of the first component, the second component is included in an amount of 90 to 110 parts by weight, the third component includes 5 to 15, and the weight ratio of Fe to the first component of 100 parts by weight can be 1.3 to 2.0 times the weight ratio of Ni to the first component of 100 parts by weight.

[0017] The second component may include Cr and may further include at least one or more selected from Co, Mo, and Cu.

[0018] The weight ratio of Cr to 100 parts by weight of the first component can be 0.63 to 1.39 times the weight ratio of Fe to 100 parts by weight of the first component.

[0019] The second component consists of Cr, Co, Mo, and Cu, and the third component may consist of Si and B.

[0020] An alloy powder according to one aspect of the present invention can be obtained by melting the above alloy, injecting a fluid into the melted alloy to atomize it, and then cooling the atomized alloy with a refrigerant.

[0021] The alloy powder may contain an amorphous phase and may have defects formed on its surface.

[0022] The alloy powder can have a reduction rate of Escherichia coli of 99.9% or more after 24 hours as measured by the KSM 0146 test method.

[0023] The above alloy powder may have a reduction rate of Escherichia coli measured by the KSM 0146 test method of 80% or more after 1 hour has elapsed.

[0024] An alloy coating body according to one aspect of the present invention a base material, and an alloy coating layer provided on the above base material, and the above alloy coating layer a first component composed of Fe and Ni, a second component composed of at least one or more selected from the group consisting of Cr, Co, Mo, and Cu, and a third component composed of at least one or more selected from the group consisting of Si, B, and P, with respect to 100 parts by weight of the above first component, the above second component is contained in 90 to 110 parts by weight, the above third component contains 5 to 15 parts by weight, the weight ratio of Fe of the above first component to 100 parts by weight of the above first component may be 1.3 to 2.0 times the weight ratio of Ni of the above first component to 100 parts by weight of the above first component.

[0025] The thickness of the above alloy coating layer may be 10 μm to 500 μm.

[0026] The porosity of the above alloy coating layer may be 5.0% or less.

[0027] The above alloy coating layer may have a reduction rate of Escherichia coli measured by the test method of JIS Z 2801 of 99.9% or more after 24 hours has elapsed.

Effects of the Invention

[0028] The alloy, alloy powder, and alloy coating body according to one aspect of the present invention are excellent in antibacterial activity against Escherichia coli, Staphylococcus aureus, and Streptococcus pneumoniae, and are excellent in economic efficiency and can be applied to a wide range of fields such as daily life.

[0029] An alloy according to one aspect of the present invention, when manufactured from alloy powder, has a very excellent antibacterial effect against bacteria in a short time and a high bactericidal and antibacterial effect against copper metal, and thus can provide a more improved antibacterial effect than copper metal substantially.

[0030] An alloy coating layer according to one aspect of the present invention can be manufactured using alloy powder, and even after being manufactured on the coating layer, the antibacterial activity against Escherichia coli, Staphylococcus aureus, and Streptococcus pneumoniae does not decrease, and it can have the same or more excellent antibacterial activity as copper metal.

[0031] The alloy powder and alloy coating layer according to one aspect of the present invention include an amorphous phase due to the amorphous forming ability of the alloy, and thus are excellent in corrosion resistance and oxidation resistance. Therefore, problems such as a decrease in antibacterial effect, discoloration, and corrosion over time do not occur, and it has the advantage of being economical due to high efficiency and long life, and is also excellent in physical properties such as the hardness of the powder and the coating layer, and can be utilized in various ways according to the application.

[0032] In the alloy according to one aspect of the present invention, the additive elements are very uniformly and evenly distributed, have a short range ordered structure and microstructural defects, and the surface energy and surface activity are very high. As a result, it is difficult for bacteria and bacteria to adhere to and grow on the surface of the amorphous alloy, and thus it can have excellent antibacterial activity.

[0033] The alloy powder and alloy coating layer according to one aspect of the present invention have high metal ion activity on the surface due to the oligodynamic effect, which is caused by the amorphous structure of the alloy, and copper, nickel, and cobalt can cause the oligodynamic effect on the surface due to the compositional characteristics of the alloy composition, and thus can have excellent antibacterial activity.

[0034] The alloy powder or alloy coating body produced using the alloy according to one aspect of the present invention is not easily affected by moisture or humidity, and thus can be used even in a high-humidity environment where bacteria and mold are likely to grow. Therefore, an excellent antibacterial effect can be obtained, and it can be applied not only to toilets, sewage drains, etc. where it was difficult to apply conventional antibacterial materials and processed products, but also to medical instruments, building handles, interior parts of ambulances, stretchers, etc. where it is necessary to reduce the risk of infection and excellent wear resistance is required. In addition, since it has excellent resistance to external contamination and antifouling properties, its utilization rate is high.

[0035] The alloy powder according to one aspect of the present invention is excellent in the ability to form an amorphous phase even when a thermal spraying coating layer is formed using a thermal spraying coating method or the like, and a coating layer containing an amorphous phase can be formed, and the hardness, corrosion resistance, oxidation resistance, etc. of the formed alloy coating layer can be further improved.

[0036] The alloy composition according to one aspect of the present invention contains copper, which is known to have antibacterial activity, at a low weight of 4 wt% or less, and since it contains an amorphous phase, excellent antibacterial activity and economic efficiency can be ensured.

Mode for Carrying Out the Invention

[0037] The present invention relates to an alloy, an alloy powder, and an alloy coating body, and preferred embodiments of the present invention will be described below. The embodiments of the present invention can be modified in various forms, and the scope of the present invention should not be construed as being limited to the embodiments described below. These embodiments are provided to explain the present invention in more detail to those having ordinary knowledge in the technical field to which the present invention pertains.

[0038] When the term "antibacterial" is used in this specification, it can be interpreted in a broad sense that includes all of suppressing, inhibiting, sterilizing, or disinfecting the growth of the required microorganisms. Here, sterilization means killing even a part of the microorganisms in the target substance, and disinfection can mean removing or killing all the microorganisms from the inside, surface, or space of the target substance.

[0039] In addition, antibacterial activity means the property of resisting microorganisms such as bacteria and molds, and more specifically, it may mean the property of suppressing the growth or proliferation of bacteria. When the expression "having antibacterial activity" is used, it can be understood that the material or sample has effects or activities such as antibacterial property or mold resistance measured by the KS test method or overseas standard test methods against specific bacteria.

[0040] In this specification, the parts by weight of the elements contained in the alloy composition can be understood to include the target composition calculated from the raw material alloy during the production of the alloy and the actual elemental composition of the produced alloy, and preferably can be calculated from the analysis results of the produced alloy components.

[0041] Hereinafter, the alloy of the present invention will be described in more detail.

[0042] The alloy of the present invention includes a first component, a second component, and a third component.

[0043] The first component is a component that can affect the physical properties, productivity, and economic efficiency of the alloy. The first component can be contained in a weight similar to or even higher than that of the second component or the third component in the total weight of the alloy. The second component can be contained in a higher weight than the third component with respect to the total weight of the alloy. Preferably, the second component can be contained in 90 to 110 parts by weight with respect to 100 parts by weight of the first component, and the third component can be contained in 5 to 15 parts by weight with respect to 100 parts by weight of the first component.

[0044] The first component is at least one selected from iron (Fe) and nickel (Ni), and can include the case where both Fe and Ni are included.

[0045] When Fe and Ni are both included as the first component, the weight of the included Fe can be higher than the weight of Ni, and the weight ratio of Fe to Ni (Fe / Ni) with respect to 100 parts by weight of the first component can be 1.3 to 2.0. Preferably it is 1.5 to 1.8, and more preferably it can be 1.59 to 1.65.

[0046] When the ratio of Fe and Ni is outside the said range, or when Fe is not included as the first component and only Ni is included, it is not preferable from the aspect of economy, and there is a possibility of inducing human body characteristics such as Ni allergy upon contact with the human body. Therefore, Fe is preferably included in the first component. Also, when the content of Ni does not reach a certain range, the high-temperature stability decreases, and oxidation of the powder, depletion of alloy elements in the coating layer, and peeling of the coating layer may occur during the manufacture of the coating layer. Therefore, Ni is preferably included in the first component within the range of the content described above.

[0047] The second component can improve the amorphous forming ability of the alloy and can contribute to improving physicochemical properties such as the hardness, corrosion resistance, and oxidation resistance of the alloy. The second component can be at least one or more selected from chromium (Cr), cobalt (Co), molybdenum (Mo), and copper (Cu). The second component can be any one or more selected from Cr and Co, Mo and Cu, and may also include all of Cr, Co, Mo, and Cu.

[0048] The second component can be included in an amount of 90 to 110 parts by weight with respect to 100 parts by weight of the first component. Preferably it can be included in an amount of 95 to 105 parts by weight, and more preferably it can be included in an amount of 99 to 102 parts by weight.

[0049] In order to ensure the antibacterial effect and corrosion resistance characteristics, the second component is preferably added in the above-mentioned content. When the content of the second component exceeds the said range, it is not only not preferable from the aspect of economy, but also the brittleness of the coating layer increases, resulting in damage by external force and the inability to ensure the antibacterial characteristics at the desired level.

[0050] The second component may essentially contain Cr, and the content of Cr contained in the second component may be higher than the total content of Co, Mo, and Cu. For example, when the second component contains Cr and further contains one or more of Mo, Co, and Cu, when the weight ratios of Cr, Co, Mo, and Cu to 100 parts by weight of the first component are a, b, c, and d respectively, the total ratio (A) of the weight ratio of Cr in the second component to the weight ratio of the remaining components excluding Cr can be calculated as a / (b + c + d), and the value can be 1.5 to 2.5, preferably 1.7 to 2.2. In order to ensure antibacterial properties, it is preferable to limit the lower limit of the content ratio (A) to the above-mentioned level. On the other hand, when the content ratio (A) exceeds the above-mentioned level, it is not preferable from the aspect of economy, and surface discoloration may occur due to a decrease in corrosion resistance.

[0051] If the content of Cr contained in the second component is compared with the content of Fe contained in the first component, the weight ratio of Cr to 100 parts by weight of the first component can be within 0.63 times to 1.39 times compared with the weight ratio of Fe to 100 parts by weight of the first component. Preferably, the weight ratio of Cr to 100 parts by weight of the first component can satisfy the range of 0.99 to 1.20 times compared with the weight ratio of Fe to 100 parts by weight of the first component.

[0052] When the content ratio of Cr and Fe is out of this range, the amorphous forming ability decreases and the ratio of the amorphous phase contained in the alloy decreases, so the antibacterial effect may decrease or the corrosion resistance may decrease.

[0053] The content of Cu contained in the second component is preferably less than the respective contents of Co, Mo, and Cr. For example, when the second component contains Cu and further contains one of Mo, Co, and Cr, when the weight ratios of Cr, Co, Mo, and Cu to 100 parts by weight of the first component are a, b, c, and d respectively, the ratio (B) that the total of the weight ratio of Cu in the second component and the weight ratio of the other components excluding Cu has can be calculated as d / (a + b + c), and the value is preferably 0.04 to 0.10, more preferably 0.05 to 0.07.

[0054] If the second component does not contain Cu or the content ratio of the remaining components to the Cu content deviates from the said range, the antibacterial performance may decrease, the corrosion resistance may decrease, and the thermal or electrical conductivity may decrease.

[0055] Cu can be contained in an amount of 0 to 9.0 parts by weight with respect to 100 parts by weight of the first component. Preferably, it can be contained in an amount of 0.1 to 8.0 parts by weight, and more preferably, it can be contained in an amount of 4.5 to 7.5 parts by weight.

[0056] When the Cu content does not meet the said range, the antibacterial activity may decrease. When the Cu content exceeds the said range, a decrease in economic efficiency due to an increase in production cost may occur.

[0057] Co can be contained in an amount of 0 to 25 parts by weight with respect to 100 parts by weight of the first component. Preferably, it can be contained in an amount of 19 to 25 parts by weight, and more preferably, it can be contained in an amount of 20 to 24 parts by weight.

[0058] When the Co content exceeds the said range, a decrease in economic efficiency due to an increase in production cost may become a problem. On the other hand, when the Co content is lower than the said range, the antibacterial activity may decrease, the high-temperature stability may decrease, and the fraction of oxides in the coating layer may increase, which may cause peeling of the coating layer due to external force.

[0059] The third component is contained in a relatively small ratio and can improve the amorphous forming ability of the alloy and impart special functions such as antibacterial activity.

[0060] The third component is at least one selected from the group consisting of silicon (Si), boron (B), and phosphorus (P), and can be contained in an amount of 5 to 15 parts by weight with respect to 100 parts by weight of the first component. Preferably, it can be contained in an amount of 7 to 13 parts by weight, and more preferably, it can be contained in an amount of 9 to 12 parts by weight.

[0061] When the content of the third component is less than the said range, the amorphous forming ability of the alloy may decrease, resulting in a reduction in corrosion resistance and hardness. When the content of the third component exceeds the said range, not only does the content of the first component or the second component relatively decrease, leading to a reduction in the strength of the alloy, but the antibacterial activity may also decrease.

[0062] When both Si and B are included as the third component, the weight ratio of Si to B within the third component (weight ratio of B to the first component 100 parts by weight / weight ratio of Si to the first component 100 parts by weight) can be in the range of 1.5 to 10. Preferably, it can be in the range of 2.5 to 9.

[0063] When the content ratio of B and Si deviates from the said range, a reduction in corrosion resistance, hardness, and strength may occur, and the antibacterial activity may also decrease.

[0064] The alloy according to one aspect of the present invention can contain additional components contained in trace amounts in addition to the above-described first component to third component. The additional components can be at least one or more of tungsten (W), yttrium (Y), manganese (Mn), aluminum (Al), zirconium (Zr), magnesium (Mg), niobium (Nb), sulfur (S), scandium (Sc), cerium (Ce), silver (Ag), titanium (Ti), and carbon (C), and these additional components can be contained in the alloy intentionally or unintentionally.

[0065] The total of the additional components can be less than 10 parts by weight with respect to 100 parts by weight of the first component. Preferably, it is less than 7.5 parts by weight, and more preferably, it can be less than 5.0 parts by weight. The content of each additional component can be less than 5.0 parts by weight with respect to 100 parts by weight of the first component. Preferably, it is less than 3.0 parts by weight, and more preferably, it can be less than 1.0 parts by weight.

[0066] When the content of the additional components exceeds the said range, the antibacterial function and mechanical properties may decrease.

[0067] The alloy powder according to one aspect of the present invention is provided using the above-described alloy. The alloy powder according to one aspect of the present invention may have an alloy composition corresponding to the above-described alloy and may include an amorphous phase. The alloy powder can be produced in powder form using a well-known method, for example, an atomizing (or atomization) method.

[0068] The atomizing method is a method of producing alloy powder by allowing a molten alloy to flow down by pressure or gravity, injecting a fluid such as gas or water into the flowing molten alloy to atomize it into fine water droplets or droplets, and then rapidly cooling the split droplets using a refrigerant such as an inert gas or water. Since the atomizing method is a well-known technique for producing metal powder, a detailed description thereof will be omitted.

[0069] In order to produce an amorphous powder by the atomizing method, it is necessary to rapidly cool the split droplets, because this is advantageous for amorphization by solidifying the molten alloy without giving it time to crystallize.

[0070] Therefore, in order to produce an alloy powder with a higher ratio of the amorphous phase, it is more advantageous to have special cooling equipment that can increase the cooling rate.

[0071] However, since the alloy according to one aspect of the present invention has excellent glass-forming ability, an alloy powder with a high ratio of the amorphous phase can be produced even using an ordinary atomizing method.

[0072] In the case of an ordinary atomizing method without special cooling equipment, an amorphous phase powder can be produced using the alloy according to one aspect of the present invention even at a cooling rate of 10 2 ~10 3 or 10 1 ~10 4 (degree / sec). Here, 10 1~2 (degree / sec) is substantially a cooling rate close to air cooling and is the cooling rate when the alloy solution is ejected into the air.

[0073] On the one hand, an alloy powder or an alloy coating layer containing an amorphous phase may have a very uniform distribution of additive elements, have a short range ordered structure, and at the same time have microstructural defects.

[0074] The defect means an irregular atomic arrangement or bonding structure that appears on a microscopic side such as the atomic structure of a substance, and includes (1) a point defect which is a zero-dimensional defect, (2) a line defect or dislocation which is a lattice distortion concentrated around a virtual line as a one-dimensional defect, and (3) a plane defect that occurs two-dimensionally and includes an external surface, a grain boundary, a stacking defect, a slip band, etc., and can be understood as a concept including the like.

[0075] Due to such microscopic defects possessed by the alloy powder or the alloy coating layer containing the amorphous phase, the amorphous alloy powder and the amorphous alloy coating layer may have the characteristic that their surface energy and activity are very high compared to the crystalline alloy.

[0076] Here, the uniform distribution of additive elements, high surface energy and activity have the effect of making it difficult for bacteria, fungi and the like to adhere to and grow on the surface of the amorphous alloy powder or the amorphous alloy coating layer, and an antibacterial effect superior to that of a crystalline metal material can be obtained.

[0077] Regarding the antibacterial activity in the alloy, alloy powder and alloy coating layer according to one aspect of the present invention, it is also interpreted that such factors act in a complex manner to have excellent antibacterial activity. Even if the specific mechanism is not clear, it can be inferred through the following examples and experimental examples that favorable antibacterial activity appears in the alloy powder and alloy coating body having a specific alloy composition and an amorphous phase.

[0078] Regarding the antibacterial activity of the alloy powder and the alloy coating layer of the present invention, the oligodynamic action can be regarded as yet another mechanism of the antibacterial activity.

[0079] The oligodynamic action is a phenomenon in which trace amounts of metal ions interfere with or kill the growth of organisms, and is known as a mechanism explaining the antibacterial action of copper, which is one of the typical antibacterial metals.

[0080] Specifically, such oligodynamic action has also been observed in metals such as silver, gold, platinum, mercury, nickel, lead, and cobalt in addition to copper. Microorganisms such as bacteria recognize metal ions as essential nutrients and absorb them into cells. However, the absorbed metal ions (including copper ions) cause effects such as making holes in the cell membrane, inhibiting metabolism, or attracting reactive oxygen species, thereby reducing the survival time of bacteria and killing them. The antibacterial activity of the alloy can be explained by the mechanism of killing bacteria and the mechanism of destroying the proteins of bacteria and viruses and decomposing genetic materials.

[0081] According to such oligodynamic action, the alloy, amorphous alloy powder, and amorphous alloy coating layer according to one aspect of the present invention can exhibit excellent effects on the oligodynamic action on the surface and have a good antibacterial effect by including the corresponding composition ratio and amorphous phase, compared to different alloys or pure copper metal.

[0082] For example, on the surface of an alloy containing copper, nickel, and cobalt, components other than copper, nickel, and cobalt are included, and the binding force, surface energy, ionization rate, etc. of each metal atom are different from those of crystalline metals and crystalline alloys. The release rate in the amorphous alloy is faster, and various types of metal ions are released, and the types and absorption rates absorbed by bacteria and the effects within bacteria can be different from each other. It is expected to have excellent antibacterial activity against a wide range of microorganisms.

[0083] Particularly, in the case of amorphous alloys, the additive elements are very uniformly distributed without the metal atoms forming a certain metal bond with a crystal structure, and fine metal atoms or metal ions at the atomic unit capable of performing trace actions are easily released. Depending on the composition of the alloy, the amount, rate, and type of metal ions released from the surface are different, and at the same time, various types of metal ions are released in a complex manner. Therefore, a significant effect can be shown quantitatively.

[0084] On the other hand, since the diameter of the alloy powder affects the surface area and is also related to the antibacterial activity of the alloy powder, in order to obtain appropriate antibacterial activity, the particle size of the alloy powder can be controlled.

[0085] The diameter of the produced alloy powder is not limited, but as a non-limiting example, it can be 1 to 150 μm, and more preferably 1 to 54 μm.

[0086] When the particle size of the alloy powder is larger than the corresponding range, the appropriate surface area decreases, and the efficiency of antibacterial activity may decrease. Powders with a particle size smaller than the corresponding range are difficult to manufacture and may be costly, and there is a possibility that they may not exhibit a sufficient antibacterial effect.

[0087] The produced alloy powder can be manufactured in a form close to spherical. The hardness (Vickers hardness) of the alloy powder is not limited and can vary depending on the purpose of the powder and the field to which it is to be applied. Without limitation, it can have a hardness of 550 to 1500 Hv, and preferably can have a hardness of 800 to 1200 Hv.

[0088] When the hardness of the alloy powder is outside the corresponding range, it may not be applicable to antibacterial products having wear resistance or being for wear resistance.

[0089] The alloy powder according to one aspect of the present invention can have excellent antibacterial activity. The types and characteristics of bacteria showing antibacterial effects are not limited, but it can mean that it is excellent in antibacterial activity against strains such as Escherichia coli, Staphylococcus aureus, and Streptococcus pneumoniae.

[0090] Antibacterial activity can be obtained as different test methods and results depending on the use, form, material, etc. of the sample. In the case of alloy powders, for example, it can be tested by methods such as KSM 0146.

[0091] Generally, when taking 24-hour culture as a reference, if there is a reduction effect of 99.9% or more in the number of bacteria, it is often recognized that there is an antibacterial effect. In the case of the alloy powder according to one aspect of the present invention, compared with a copper metal sample known to have excellent antibacterial effect, the reduction effect of the number of bacteria after 24 hours can be similar or more. The reduction rate of the number of bacteria after 1 hour can be 80% or more.

[0092] The alloy coating body according to one aspect of the present invention can be such that an alloy coating layer formed from the above-described alloy powder is formed on a base material to form a coating body.

[0093] The base material on which the alloy coating body is formed is not limited, and is not limited by its substance, component, size, use, etc.

[0094] The method for forming the alloy coating layer and the coating method according to the corresponding example are not limited, but a spraying coating method such as a high-velocity oxygen fuel spray (HVOF), plasma spraying, twin wire arc spray (TWAS), cold spray, vacuum plasma spraying, low-pressure plasma spraying, etc. or a cladding method such as laser cladding, etc., which can utilize the above-described alloy powder to manufacture an alloy coating layer, is preferably used.

[0095] The raw material used for coating is not limited as long as it is in the form of the above-described alloy composition, and alloy powders, alloy wires, fluxed cored wires, etc. can be used.

[0096] On the one hand, the thickness of the alloy coating layer formed on the base material is not limited and can vary according to the type of the base material on which the coating layer is formed, the thickness of the base material, the intended use, the use environment, etc. Preferably, the thickness can be 10 μm to 500 μm, more preferably 50 to 300 μm.

[0097] The antibacterial activity of the alloy coating layer can be measured by various test methods according to the form, conditions, etc. of the sample. For example, the antibacterial activity of the alloy coating layer can be evaluated by methods such as JIS Z 2801 or FC-TM-20.

[0098] Generally, based on a 24-hour culture, when there is a reduction effect of 99.9% or more in the number of bacteria, the alloy coating layer is often recognized as having an antibacterial effect. In the case of the alloy coating layer according to one aspect of the present invention, the reduction effect of the number of bacteria after 24 hours can be similar to or greater than that of a copper metal sample known to have excellent antibacterial effects. The reduction rate of bacteria after 1 hour can be 80% or more.

[0099] The alloy coating layer according to one aspect of the present invention can be an amorphous alloy coating layer containing an amorphous phase. Since the alloy coating layer contains an amorphous phase, it can have the excellent physical properties of amorphous alloys.

[0100] For example, the alloy coating layer can have a Vickers hardness of 550 to 1500 Hv, preferably 800 to 1200 Hv.

[0101] When the hardness of the alloy coating layer is lower than the corresponding range, the wear resistance decreases, and surface damage, scratches, or abrasions may occur. When it is higher than the corresponding range, cracks, fissures, or surface damage due to brittleness may occur.

[0102] In addition, the alloy coating layer according to one aspect of the present invention is excellent in corrosion resistance, wear resistance, and oxidation resistance. During use, the coating layer is less likely to peel off or corrode, which not only improves the lifespan of the coating layer, but also enables the antibacterial activity of the alloy coating layer to be maintained for a long time without decline.

[0103] Moreover, the porosity of the alloy coating layer according to one aspect of the present invention can vary depending on the particle size of the powder used for the coating, the coating method, and the coating conditions. The lower the porosity of the alloy coating layer, the more preferable it is, and specifically, it can be within 5.0%, preferably within 1.0%.

[0104] If the porosity exceeds the corresponding range, there may be a decrease in hardness or wear resistance due to a decrease in the quality of the alloy coating layer, and problems such as easy penetration of corrosive substances and a decrease in internal corrosion resistance may occur. In addition, the adhesion and growth of bacteria may be facilitated.

[0105] The application fields of the alloy powder and the alloy coating body according to the present invention are not limited, and they can be utilized in various fields such as medical, health, daily necessities, and household appliances where antibacterial activity can be utilized.

Examples

[0106] Hereinafter, the present invention will be described more specifically with reference to examples. It should be noted that the following examples are for the purpose of understanding the present invention and are not intended to limit the scope of the rights of the present invention. The scope of the rights of the present invention can be determined by the matters described in the claims and those reasonably inferred therefrom.

[0107] (Example) Examples 1 to 7 - Production of alloy powder An alloy prepared with a composition having components and parts by weight as shown in Table 1 below was melted, atomized using an atomizer under an inert gas atmosphere, and then cooled to produce an alloy powder containing an amorphous phase. The average particle size of the produced powder was measured using a laser particle size analyzer, and the results are also described in Table 1.

[0108]

Table 1

[0109] Examples 8 - 14 - Production of Alloy Coating Bodies Using the alloy powders produced in Examples 1 - 7, with a high - velocity oxygen fuel (HVOF) spraying equipment (Oerlikon Metco Diamond Jet series HVOF gas fuel spray system), using oxygen and propane gas as fuel, with a spraying distance of 30 cm, an alloy coating body was formed on the base material by the high - velocity oxygen fuel spray (HVOF) method. The equipment and conditions used at this time are specifically described below.

[0110] -DJ Gun HVOF- [Conditions] Gun type: Hybrid, air cap: 2701, LPG Flow: 160 SCFH, LPG Pressure: 90 PSI, Oxygen flow: 550 SCFH, Oxygen Pressure: 150 PSI, Air flow: 900 SCFH, Air Pressure: 100 PSI, Nitrogen flow: 28 SCFH, Nitrogen Pressure: 150 PSI, Gun speed: 100 m / min, Gun pitch: 3.0 mm, Feeder rate: 45 g / min, Stand - off distance: 250 mm

[0111] (Comparative Example) Comparative Examples 1 - 6 - Production of Alloy Powders After producing an alloy satisfying the component compositions in Table 2 below, crystalline metal powders and alloy powders containing an amorphous phase were produced by the methods as in Examples 1 - 7. The particle sizes of the powders produced were measured using a laser particle size analyzer, and the results are described together with Table 2. The fraction of the amorphous phase of each powder was measured using EBSD (Electron backscatter diffraction), and the results are described together with Table 2. "○" in the presence or absence of amorphous means that the fraction of the amorphous phase is 10% by volume or more, and "×" in the presence or absence of amorphous means that the fraction of the amorphous phase is less than 10% by volume.

[0112]

Table 2

[0113] Comparative Examples 7 - 10 - Production of Alloy Coated Bodies The alloy powders of Comparative Examples 1 - 4 were coated on the base material under the equipment and conditions as in Examples 8 - 14 to obtain alloy coated bodies provided with alloy coating layers.

[0114] (Experimental Example) Experimental Example 1 - Composition Analysis of Produced Alloy Powders As a result of analyzing the alloy powders of Examples 1 - 7 using ICP (Inductively Coupled Plasma Spectrometer), it was confirmed that the alloy component contents of the alloy used for producing the alloy powders and the alloy powders produced using this were the same, and even if there were some differences, they were at a level within the range of manufacturing errors.

[0115] Experimental Example 2 - Experiment on Antibacterial Activity of Alloy Powders To evaluate the antibacterial activities of the alloy powders of Examples 1 - 7 and Comparative Examples 1 - 6, the shaking flask method was carried out based on the test method shown in Korean Industrial Standard KSM 0146 (2003). Using the cultures of Escherichia coli, Staphylococcus aureus, and Klebsiella pneumoniae, the final concentration of the bacterial culture solution was 1 - 5×10 5After preparing to a concentration of CFU / ml, a sample was added thereto at a ratio of 0.09 g / ml.

[0116] 1 g of the alloy powder of Examples 1 to 7 and Comparative Examples 1 to 6 was introduced, and the flask was subjected to shaking culture at 37 ± 1 °C for 24 hours at 120 rpm. Then, the viable cell count before and after the culture of each group was measured.

[0117] As the antibacterial activity, the bacterial reduction rate, which indicates the number of bacteria observed after 24 hours as a percentage with respect to the initial number of bacteria, was calculated, and the results of Examples 1 to 5 and Comparative Examples 1 to 6 are shown in Table 3 below.

[0118] [Table 3]

[0119] It was found that Examples 1 and Comparative Example 1 showed a reduction rate of 99.9% or more against all of Escherichia coli, Staphylococcus aureus, and Klebsiella pneumoniae, indicating excellent antibacterial activity. In the case of Comparative Examples 2 to 6, it was found that the antibacterial activity against Escherichia coli, Staphylococcus aureus, and Klebsiella pneumoniae was relatively low.

[0120] Experimental Example 3 - Experiment on Antibacterial Activity of Alloy Coating Layer To evaluate the antibacterial activity of the alloy coating body of Example 8, an experiment on antibacterial activity was conducted by the film adhesion method based on the test method shown in JIS Z 2801.

[0121] The test conditions were as follows: temperature 37 to 38 °C, time 23 to 24 hours, a coating body with a size of 50 mm in both width and length was used as the sample. After culturing Escherichia coli, Staphylococcus aureus, and Klebsiella pneumoniae in a medium, the initial number of bacteria was measured. After allowing the test bacterial solution to stand-culture for 24 hours at 35 ± 1 °C and a relative humidity of 90% with the sample piece in contact with the medium, the number of bacteria was measured, and the reduction ratio was shown as in Table 4 below.

[0122] [Table 4]

[0123] Even in the alloy-coated body of Example 8, it was found that the reduction rate against all of Escherichia coli, Staphylococcus aureus, and Streptococcus pneumoniae was 99.9% or more, indicating excellent antibacterial activity. When compared with the results of the antibacterial experiment of Example 1, it was confirmed that the coated body obtained by thermal spraying the powder also had antibacterial activity at a level similar to that of the powder.

[0124] Experimental Example 4 - Experiment on the 1-hour antibacterial effect of alloy powder An experiment was conducted in the same manner as Experimental Example 2, except that the shaking culture time of the powders of Example 1 and Comparative Example 1 was changed from 24 hours to 1 hour, and the results are shown in Table 5 below.

[0125] [Table 5]

[0126] As a result, it was confirmed that the powder of Example 1 had a reduction rate of Escherichia coli during 1 hour that was 2 to 3 times that of the copper powder of Comparative Example 1, and had antibacterial activity more than twice as excellent as that of the copper powder.

[0127] Experimental Example 5 - Evaluation of antibacterial durability by repeated inoculation of test pieces with amorphous alloy coating and evaluation of antibacterial properties under severe conditions [Evaluation of antibacterial durability by repeated inoculation] After preparing a stainless steel (STS) test piece with a size of 2 cm × 2 cm, an amorphous alloy coating layer was formed on the surface of some of the test pieces using the alloy powder of Example 1. At this time, the amorphous alloy coating layer was manufactured by applying the same method as in Examples 8 to 14.

[0128] The surfaces of the prepared uncoated test pieces and the test pieces with amorphous alloy coatings were washed with 70% ethanol and then dried in a clean bench for about 15 hours. A mixed bacterium of Escherichia coli, Staphylococcus aureus, and Klebsiella pneumonia was mixed with the dried test pieces using 1 / 500 NB medium and inoculated 5 times at a quantity of 10 5 cfu / ml. After inoculation, it was covered with a UV-sterilized cover glass (18 mm × 18 mm) and cultured in a thermostatic and humidistatic chamber maintained at 36°C and 90% RH. At the time point 2 hours after each inoculation, the bacteria were recovered by suspending each test piece with 10 ml of letheen medium by vortexing. After diluting to a concentration at which the number of bacteria could be confirmed, it was poured into TSA medium and cultured at 36°C for 24 hours, and then the number of bacteria was confirmed and the bacterial reduction rate was described in Table 6.

[0129] [Table 6]

[0130] As shown in Table 6, it can be confirmed that the test pieces with amorphous alloy coatings maintain antibacterial power even during 5 repeated inoculations, while the uncoated test pieces lose antibacterial power under the same conditions.

[0131] [Evaluation of Antibacterial Properties under Severe Conditions] The same test pieces as those used in the evaluation of antibacterial durability by repeated inoculation were prepared.

[0132] The surfaces of the prepared uncoated test pieces and the test pieces with amorphous alloy coatings were washed with 70% ethanol and then dried in a clean bench for about 15 hours. A mixed bacterium of Escherichia coli, Staphylococcus aureus, and Klebsiella pneumonia was mixed with the dried test pieces using 1 / 500 NB medium and 10 7Inoculated once with the amount of cfu / ml, covered with a UV-sterilized cover glass (18 mm × 18 mm) after inoculation, and cultured in a thermostatic and humidistatic chamber maintained at 36 °C and 90% RH. At the time points of 1 hour, 2 hours, 3 hours, 9 hours, and 18 hours after inoculation, each test piece was suspended (vortexing) in 10 ml of letheen medium to recover the bacteria. After diluting to a concentration at which the number of bacteria could be confirmed, it was poured into TSA medium and cultured at 36 °C for 24 hours, and then the number of bacteria was confirmed, and the reduction rate of the number of bacteria was described in Table 7.

[0133]

Table 7

[0134] As shown in Table 7, the antibacterial activity of the test piece of the amorphous alloy coating was confirmed at the time point after 9 hours, while the antibacterial activity of the uncoated test piece was not confirmed even at the time point after 18 hours.

[0135] As described above, the present invention has been described in detail with examples, but examples in different forms are also possible. Therefore, the technical idea and scope of the claims described below are not limited to the examples.

Claims

1. a first component consisting of Fe and Ni, a second component consisting of at least one or more selected from the group consisting of Cr, Co, Mo, and Cu, a third component consisting of at least one or more selected from the group consisting of Si, B, and P, and comprising: with respect to 100 parts by weight of the first component, the second component is contained in an amount of 90 to 110 parts by weight, the third component contains 5 to 15 parts by weight, the weight ratio of Fe to 100 parts by weight of the first component is 1.3 to 2.0 times the weight ratio of Ni to 100 parts by weight of the first component, an alloy, the alloy is characterized by containing an amorphous phase, an alloy for antibacterial use.

2. the second component contains Cr, the alloy for antibacterial use according to claim 1, further comprising any one or more selected from Co, Mo, and Cu.

3. the weight ratio of Cr to 100 parts by weight of the first component is 0.63 times to 1.39 times the weight ratio of Fe to 100 parts by weight of the first component, the alloy for antibacterial use according to claim 2.

4. the second component consists of Cr, Co, Mo, and Cu, the alloy for antibacterial use according to claim 1, wherein the third component consists of Si and B.

5. The alloy according to any one of claims 1 to 4 is melted, a fluid is injected into the melted alloy to atomize the alloy, and then the atomized alloy is cooled with a refrigerant, an antibacterial alloy powder characterized by being obtained.

6. the alloy powder contains an amorphous phase and has defects formed on the surface, the antibacterial alloy powder according to claim 5.

7. the antibacterial alloy powder according to claim 5, wherein the reduction rate of Escherichia coli measured by the KSM 0146 test method is 99.9% or more after 24 hours.

8. the antibacterial alloy powder according to claim 6, wherein the reduction rate of Escherichia coli measured by the KSM 0146 test method is 80% or more after 1 hour.

9. a base material, an alloy coating layer provided on the base material, and comprising: the alloy coating layer, a first component consisting of Fe and Ni, a second component consisting of at least one or more selected from the group consisting of Cr, Co, Mo, and Cu, a third component consisting of at least one or more selected from the group consisting of Si, B, and P, and comprising: with respect to 100 parts by weight of the first component, the second component is contained in an amount of 90 to 110 parts by weight, The third component contains 5 to 15 parts by weight, and the weight ratio of Fe to 100 parts by weight of the first component is 1.3 to 2.0 times the weight ratio of Ni to 100 parts by weight of the first component. The alloy coating body for antibacterial use, wherein the alloy coating layer contains an amorphous phase.

10. The alloy coating body for antibacterial use according to claim 9, wherein the thickness of the alloy coating layer is 10 μm to 500 μm.

11. The alloy coating body for antibacterial use according to claim 9, wherein the porosity of the alloy coating layer is 5.0% or less.

12. The alloy coating body for antibacterial use according to claim 9, wherein the reduction rate of Escherichia coli measured by the test method of JIS Z 2801 is 99.9% or more after 24 hours.

Images