A method for preparing antibacterial stainless steel feed for in-situ preparation of antibacterial components

Abstract

The invention discloses a method for preparing an antibacterial stainless steel feedstock for preparing antibacterial components in situ, comprising the following steps: S1, stirring and dissolving a titanate coupling agent in anhydrous ethanol to obtain A1; S2, adding nitrate or acetate of silver, copper or zinc to A1, and then stirring and dissolving to obtain A2; S3, stirring and mixing A2 with a polymer binder to obtain A3; S4, refining A3 and water vapor combined atomized stainless steel powder, crushing and granulating to obtain the antibacterial stainless steel feedstock. The phthalate coupling agent added in the invention can allow the nitrate or acetate of silver, copper or zinc to be evenly combined with the polymer binder, and then evenly mixed with the water vapor combined atomized stainless steel powder. In the next step of preparing antibacterial stainless steel cutting tools, when the nitrate or acetate of silver, copper or zinc is thermally decomposed into particles of silver, copper or zinc, it is well dispersed in the stainless steel cutting tools to achieve the maximum antibacterial effect. The surfactants silver stearate, copper stearate and zinc stearate added at the same time are also decomposed into uniformly dispersed ultrafine particles of silver, copper and zinc at high temperature, further improving the antibacterial effect.

Description

Technical Field

[0001] The invention relates to the technical field of antibacterial stainless steel, and in particular to an antibacterial stainless steel feed material, an antibacterial stainless steel cutting tool and a preparation method thereof. Background Art

[0002] Harmful microorganisms in nature pose a serious threat to human health. Millions of people die from bacterial infections every year. Humans are infected with bacteria mainly through food and contact with bacteria-carrying objects. Kitchen utensils, daily necessities, and especially medical instruments that are in direct contact with food often become the source of microbial growth and reproduction. The food industry, medical and health industry, and ordinary households have an increasing demand for kitchen utensils and medical instruments with excellent antibacterial and antimicrobial properties.

[0003] Silver, copper, and zinc have the ability to inhibit bacterial adhesion, have broad-spectrum antibacterial activity, and have long-lasting antibacterial activity, and are often added to stainless steel to prepare antibacterial stainless steel. Traditional processes make it difficult to evenly add additives such as silver, copper, and zinc to stainless steel metal.

[0004] The addition of most elements will have a significant inhibitory effect on the static recrystallization behavior of stainless steel, thereby affecting the strength and corrosion resistance of stainless steel.

[0005] Metal Injection Molding (MIM) is a technology that combines powder metallurgy and plastic injection molding. It has the advantages of uniform distribution of material elements, suitable for the production of complex-shaped products, high product precision, and high production efficiency. Silver, copper, and zinc metal powders are directly added to stainless steel powder, which has the disadvantages of being difficult to distribute evenly and the particles are not fine enough. This patent uses the in-situ generation principle of silver, copper, and zinc precursors to prepare antibacterial stainless steel feed.

[0006] Silver, copper and zinc nanoparticles are prepared by thermal decomposition of silver nitrate, copper nitrate, zinc nitrate or silver acetate, copper acetate and zinc acetate precursors, which can be well dispersed in stainless steel products to achieve the maximum antibacterial effect. At the same time, the added surfactants silver stearate, copper stearate and zinc stearate are also decomposed into uniformly dispersed ultrafine particles of silver, copper and zinc at high temperatures, further improving the antibacterial effect. Summary of the invention

[0007] The present invention provides a method for preparing an antibacterial stainless steel feedstock for in-situ preparation of antibacterial components. The prepared antibacterial stainless steel feedstock has the advantages of uniform distribution and fine particles, and can be well dispersed in stainless steel products to achieve the maximum antibacterial effect. To achieve the above purpose, the present invention adopts the following technical solutions:

[0008] A method for preparing an antibacterial stainless steel feedstock for in-situ preparation of antibacterial components, wherein the polymer binder comprises the following components in percentage by weight:

[0009] Polyoxymethylene 80-88%;

[0010] High-density polyethylene 4-10%;

[0011] Ethylene-vinyl acetate copolymer 2-8%;

[0012] Solid paraffin 1.8-5%;

[0013] Surfactant 0.1~2.6%;

[0014] Antioxidant 0.2~0.5%.

[0015] Polyoxymethylene has good fluidity and high green strength after injection, and is not easy to deform. It can be quickly catalytically decomposed into formaldehyde in an acidic atmosphere, thereby achieving rapid degreasing and high production efficiency. The chemical stability of high-density polyethylene and ethylene-vinyl acetate copolymer can ensure that the degreased green body has sufficient strength during catalytic degreasing and does not deform.

[0016] A method for preparing an antibacterial stainless steel feedstock for in-situ preparation of an antibacterial component, wherein the antibacterial stainless steel feedstock comprises the following components in percentage by mass:

[0017] Water-gas combined atomization stainless steel powder 86-94%;

[0018] Silver nitrate, copper nitrate, zinc nitrate or silver acetate, copper acetate, zinc acetate, one or more 0.05-4%;

[0019] Ethanol 2.9-10%;

[0020] Titanate coupling agent 0.5-3%.

[0021] A method for preparing an antibacterial stainless steel feedstock for in-situ preparation of antibacterial components comprises the following steps:

[0022] S1 and a titanate coupling agent are stirred and dissolved in anhydrous ethanol to obtain A1;

[0023] Add one or more powders of silver nitrate, copper nitrate, zinc nitrate or silver acetate, copper acetate, zinc acetate to S2 and A1, and then stir and dissolve to obtain A2;

[0024] S3, A2 and a polymer binder are stirred and mixed to obtain A3;

[0025] S4, A3 and water vapor are combined to atomize stainless steel powder for internal mixing, crushing and granulation to obtain feed material.

[0026] A method for preparing an antibacterial stainless steel feedstock for in-situ preparation of antibacterial components, in step S4, the A3 and the water vapor atomized stainless steel powder are mixed in a mixer, and the mixing process parameters are:

[0027] The rotor speed is 30-40 rpm;

[0028] The mixing temperature is 180-190°C;

[0029] Refining for 60 to 90 minutes.

[0030] According to the method for preparing an antibacterial stainless steel feedstock for in-situ preparation of antibacterial components, an antibacterial stainless steel cutting tool is prepared, comprising the following steps:

[0031] B1. Injection: Add the antibacterial stainless steel feed material into an injection machine, and the injection machine injects the antibacterial stainless steel feed material into the cutting tool mold cavity, and demolds to obtain a cutting tool injection green body, the injection temperature is 190° C., and the mold temperature is 95° C.;

[0032] B2, degreasing: the injection green body is subjected to oxalic acid catalytic degreasing treatment to form a degreasing body, the degreasing environment temperature is controlled to be 135°C, the acid passing time is 8h, and the acid feeding speed is: 9g / min;

[0033] B3, sintering: sintering the degreased blank to form a sintered blank; the sintering temperature is 1320°C, the holding time is 8h, the sintering atmosphere is N2, the partial pressure is 10kPa, and the blank is cooled with the furnace;

[0034] B4. Heat treatment: heat treatment of the sintered blank; 1000°C for 30 min, quenching with 10% salt water, and then tempering at 200°C;

[0035] B5. Sharpening: sharpening the sintered blank after the heat treatment to obtain an antibacterial stainless steel cutting tool.

[0036] Compared with the prior art, the present invention has the following beneficial effects:

[0037] 1. The antibacterial stainless steel cutting tools are made by metal injection molding, which is easy to achieve the dispersion and uniform distribution of antibacterial elements, and is more conducive to the full play of the antibacterial effect;

[0038] 2. The feed material is degreased by oxalic acid catalysis, and the degreased ash billet has good shape retention.

[0039] 3. The antibacterial stainless steel cutting tool has high dimensional accuracy and excellent mechanical properties. It can be mass-produced with little or no subsequent machining and low cost. DETAILED DESCRIPTION

[0040] Example 1

[0041] A method for preparing an antibacterial stainless steel feedstock for in-situ preparation of antibacterial components, wherein the polymer binder comprises the following components in parts by weight:

[0042] Polyoxymethylene 80%;

[0043] High density polyethylene 10%;

[0044] Ethylene-vinyl acetate copolymer 6%;

[0045] Solid paraffin 2%;

[0046] Copper stearate 1.5%;

[0047] Antioxidant AO-3 0.5%.

[0048] A method for preparing an antibacterial stainless steel feedstock for in-situ preparation of an antibacterial component, wherein the antibacterial stainless steel feedstock comprises the following components in percentage by mass:

[0049] 304L stainless steel powder 94%;

[0050] Silver nitrate 0.1%;

[0051] Ethanol 2.9%;

[0052] Titanate coupling agent KR-TTS 3%.

[0053] A method for preparing an antibacterial stainless steel feedstock for in-situ preparation of antibacterial components comprises the following steps:

[0054] S1 and titanate coupling agent KR-TTS are stirred and dissolved in anhydrous ethanol to obtain A1;

[0055] Add silver nitrate to S2 and A1, then stir and dissolve to obtain A2;

[0056] S3, A2 and a polymer binder are stirred and mixed to obtain A3;

[0057] S4, A3 and 304L stainless steel powder are mixed, crushed and granulated to obtain feed material, and the mixing process parameters are: rotor speed 30rpm, mixing temperature 190℃, mixing for 70min. Then stop heating, cool, crush and granulate to obtain feed material.

[0058] The mass ratio of polymer binder to water vapor co-atomized 304 stainless steel powder is 7:93.

[0059] Example 2

[0060] A method for preparing an antibacterial stainless steel feedstock for in-situ preparation of antibacterial components, wherein the polymer binder comprises the following components in parts by weight:

[0061] Polyoxymethylene 83%;

[0062] High-density polyethylene 6%;

[0063] Ethylene-vinyl acetate copolymer 8%;

[0064] Solid paraffin 1.8%;

[0065] Stearic acid 0.9%;

[0066] Silver stearate 0.1%;

[0067] Antioxidant AO-14 0.2%.

[0068] A method for preparing an antibacterial stainless steel feedstock for in-situ preparation of an antibacterial component, wherein the antibacterial stainless steel feedstock comprises the following components in percentage by mass:

[0069] 316L stainless steel powder 86%;

[0070] Zinc nitrate 4%;

[0071] Ethanol 8%;

[0072] Titanate coupling agent OLT-999 2%.

[0073] A method for preparing an antibacterial stainless steel feedstock for in-situ preparation of antibacterial components comprises the following steps:

[0074] S1 and titanate coupling agent OLT-999 were stirred and dissolved in anhydrous ethanol to obtain A1;

[0075] Add zinc nitrate to S2 and A1, then stir and dissolve to obtain A2;

[0076] S3, A2 and a polymer binder are stirred and mixed to obtain A3;

[0077] S4, A3 and 316L stainless steel powder are mixed, crushed and granulated to obtain feed material, and the mixing process parameters are: rotor speed of 40rpm, mixing temperature of 190℃, mixing for 60min. Then stop heating, cool, crush and granulate to obtain feed material.

[0078] The mass ratio of polymer binder to water vapor co-atomized 316L stainless steel powder is 8:92.

[0079] Example 3

[0080] A method for preparing an antibacterial stainless steel feedstock for in-situ preparation of antibacterial components, wherein the polymer binder comprises the following components in parts by weight:

[0081] Polyoxymethylene 85%;

[0082] High density polyethylene 5%;

[0083] Ethylene-vinyl acetate copolymer 2%;

[0084] Solid paraffin 5%;

[0085] Zinc stearate 2.6%;

[0086] Antioxidant AO-4 0.2%

[0087] Antioxidant AO-430.2%.

[0088] A method for preparing an antibacterial stainless steel feedstock for in-situ preparation of an antibacterial component, wherein the antibacterial stainless steel feedstock comprises the following components in percentage by mass:

[0089] 420 stainless steel powder 88%;

[0090] Copper acetate 0.5%;

[0091] Ethanol 10%;

[0092] Titanate coupling agent TC-130 1.5%.

[0093] A method for preparing an antibacterial stainless steel feedstock for in-situ preparation of antibacterial components comprises the following steps:

[0094] S1 and titanate coupling agent TC-130 were stirred and dissolved in anhydrous ethanol to obtain A1;

[0095] Add copper acetate to S2 and A1, then stir and dissolve to obtain A2;

[0096] S3, A2 and a polymer binder are mixed to obtain A3;

[0097] S4, A3 and 420 stainless steel powder are mixed, crushed and granulated to obtain feed material, and the mixing process parameters are: rotor speed 30rpm, mixing temperature 180℃, mixing for 90min. Then stop heating, cool, crush and granulate to obtain feed material.

[0098] The mass ratio of polymer binder to water vapor co-atomized stainless steel powder is 9:91.

[0099] Example 4

[0100] A method for preparing an antibacterial stainless steel feedstock for in-situ preparation of antibacterial components, wherein the polymer binder comprises the following components in parts by weight:

[0101] Polyoxymethylene 88%;

[0102] High-density polyethylene 4%;

[0103] Ethylene-vinyl acetate copolymer 3%;

[0104] Solid paraffin 3%;

[0105] Pentaerythritol stearate 1.0%

[0106] Zinc stearate 0.6%;

[0107] Silver stearate 0.1%;

[0108] Antioxidant AO-46 0.3%.

[0109] A method for preparing an antibacterial stainless steel feedstock for in-situ preparation of an antibacterial component, wherein the antibacterial stainless steel feedstock comprises the following components in percentage by mass:

[0110] 17 4PH stainless steel powder 89.5%;

[0111] Copper nitrate 2.95%;

[0112] Silver acetate 0.05%;

[0113] Ethanol 7%;

[0114] Titanate coupling agent TAE 0.5%.

[0115] A method for preparing an antibacterial stainless steel feedstock for in-situ preparation of antibacterial components comprises the following steps:

[0116] S1 and titanate coupling agent TAE are stirred and dissolved in anhydrous ethanol to obtain A1;

[0117] Add copper nitrate and silver acetate to S2 and A1, then stir and dissolve to obtain A2;

[0118] S3, A2 and a polymer binder are stirred and mixed to obtain A3;

[0119] S4, A3 and 17 4PH stainless steel powder are mixed, crushed and granulated to obtain feed material, and the mixing process parameters are: rotor speed of 40rpm, mixing temperature of 185℃, mixing for 80min. Then stop heating, cool, crush and granulate to obtain feed material.

[0120] The mass ratio of polymer binder to water vapor co-atomized stainless steel powder is 11:89.

[0121] Comparative Example 1

[0122] The polymer binder in this comparative example is the same as that in Example 1.

[0123] The antibacterial stainless steel feed of this comparative example does not contain silver nitrate, and the proportions of other ingredients remain unchanged.

[0124] The method for preparing the antibacterial stainless steel feed of this comparative example comprises the following steps:

[0125] S1 and titanate coupling agent KR-TTS are stirred and dissolved in anhydrous ethanol to obtain A1;

[0126] S2, A1 and a polymer binder are mixed to obtain A2;

[0127] S3, A2 and 304L stainless steel powder are mixed, crushed and granulated to obtain feed material, and the mixing process parameters are: rotor speed 30rpm, mixing temperature 190℃, mixing for 70min. Then stop heating, cool, crush and granulate to obtain feed material.

[0128] Comparative Example 2

[0129] The polymer binder in this comparative example is the same as that in Example 2.

[0130] The antibacterial stainless steel feed in this comparative example does not contain zinc nitrate, and the proportions of other ingredients remain unchanged.

[0131] The method for preparing the antibacterial stainless steel feed of this comparative example comprises the following steps:

[0132] S1 and titanate coupling agent OLT-999 were stirred and dissolved in anhydrous ethanol to obtain A1;

[0133] S2, A1 and a polymer binder are mixed to obtain A2;

[0134] S3, A2 and 316L stainless steel powder are mixed, crushed and granulated to obtain feed material, and the mixing process parameters are: rotor speed of 40rpm, mixing temperature of 190℃, mixing for 60min. Then stop heating, cool, crush and granulate to obtain feed material.

[0135] Comparative Example 3

[0136] The polymer binder in this comparative example is the same as that in Example 3.

[0137] The antibacterial stainless steel feed of this comparative example does not contain copper acetate, and the proportions of other components remain unchanged.

[0138] The method for preparing the antibacterial stainless steel feed of this comparative example comprises the following steps:

[0139] S1 and titanate coupling agent TC-130 were stirred and dissolved in anhydrous ethanol to obtain A1;

[0140] S2, A1 and a polymer binder are mixed to obtain A2;

[0141] S3, A2 and 420 stainless steel powder are mixed, crushed and granulated to obtain feed material, and the mixing process parameters are: rotor speed 30rpm, mixing temperature 180℃, mixing for 90min. Then stop heating, cool, crush and granulate to obtain feed material.

[0142] Comparative Example 4

[0143] The polymer binder in this comparative example is the same as that in Example 4.

[0144] The antibacterial stainless steel feed in this comparative example does not contain copper nitrate and silver acetate, and the proportions of other components remain unchanged.

[0145] The method for preparing the antibacterial stainless steel feed of this comparative example comprises the following steps:

[0146] S1 and titanate coupling agent TAE are stirred and dissolved in anhydrous ethanol to obtain A1;

[0147] S2, A1 and a polymer binder are mixed to obtain A2;

[0148] S3, A2 and 17 4PH stainless steel powder are mixed, crushed and granulated to obtain feed material, and the mixing process parameters are: rotor speed of 30rpm, mixing temperature of 190℃, mixing for 70min. Then stop heating, cool, crush and granulate to obtain feed material.

[0149] According to the method for preparing an antibacterial stainless steel feed material for in-situ preparation of antibacterial components, an antibacterial stainless steel cutting tool is prepared, comprising the following steps:

[0150] B1. Injection: Add the antibacterial stainless steel feed material into an injection machine, and the injection machine injects the antibacterial stainless steel feed material into the cutting tool mold cavity, and demolds to obtain a cutting tool injection green body, the injection temperature is 190° C., and the mold temperature is 95° C.;

[0151] B2, degreasing: the injection green body is subjected to oxalic acid catalytic degreasing treatment to form a degreasing body, the degreasing environment temperature is controlled to be 135°C, the acid passing time is 8h, and the acid feeding speed is: 9g / min;

[0152] B3, sintering: sintering the degreased blank to form a sintered blank; the sintering temperature is 1320°C, the holding time is 8h, the sintering atmosphere is N2, the partial pressure is 10kPa, and the blank is cooled with the furnace;

[0153] B4. Heat treatment: heat treatment of the sintered blank; 1000°C for 30 min, quenching with 10% salt water, and then tempering at 200°C;

[0154] B5. Sharpening: sharpening the sintered blank after the heat treatment to obtain an antibacterial stainless steel cutting tool.

[0155] The antibacterial stainless steel cutting tools were tested by the "adhesive film method" proposed by the Japanese Food Analysis Center, and Escherichia coli and Staphylococcus aureus were cultured and observed on the surface of the sample at 35°C for 24 hours. Table 1 Antibacterial performance test results of the antibacterial stainless steel cutting tools prepared based on antibacterial stainless steel feed materials of Examples 1-4 and the antibacterial stainless steel cutting tools of Comparative Examples 1-4.

[0156]

[0157] Table 1 shows that the antibacterial properties of the cutting tools prepared in the four embodiments are good. The comparative example is the preparation of silver, copper and zinc nanoparticles by thermal decomposition of silver nitrate, copper nitrate, zinc nitrate or silver acetate, copper acetate and zinc acetate precursors, but the surfactants silver stearate, copper stearate and zinc stearate are also decomposed into uniformly dispersed ultrafine particles of silver, copper and zinc at high temperature, which have a certain antibacterial effect.

[0158] The above description is only a specific embodiment of the present invention, and does not limit the patent scope of the present invention. Any equivalent transformation made by the present invention, or directly or indirectly applied in other related technical fields, is also included in the patent protection scope of the present invention.

Claims

1. A method for preparing an antibacterial stainless steel feedstock for in-situ preparation of antibacterial components, characterized in that: The following steps are involved: S1 and a titanate coupling agent are stirred and dissolved in anhydrous ethanol to obtain A1; Add one or more powders of silver nitrate, copper nitrate, zinc nitrate or silver acetate, copper acetate, zinc acetate to S2 and A1, and then stir and dissolve to obtain A2; S3, A2 and a polymer binder are stirred and mixed to obtain A3; S4, mixing A3 with water vapor and atomized stainless steel powder, crushing and granulating to obtain antibacterial stainless steel feed.

2. The method for preparing an antibacterial stainless steel feedstock for in-situ preparation of antibacterial components according to claim 1, characterized in that: The titanate coupling agent is KR-TTS, KR-9S, OLT-999, OLT-951, TC-130, TC-131, TC-1, and TAE.

3. The method for preparing an antibacterial stainless steel feedstock for in-situ preparation of antibacterial components according to claim 1, characterized in that: The water-gas combined atomization stainless steel powder includes 304L stainless steel powder, 316L stainless steel powder, 420 stainless steel powder, 430 stainless steel powder, 440C stainless steel powder and 17 4PH stainless steel powder.

4. The method for preparing an antibacterial stainless steel feedstock for in-situ preparation of antibacterial components according to claim 1, characterized in that: More than 95% of the particle sizes of the water-gas combined atomized stainless steel powder are within the range of 7 to 10 μm.

5. The method for preparing an antibacterial stainless steel feedstock for in-situ preparation of antibacterial components according to claim 1, characterized in that: The antibacterial stainless steel feed comprises the following components in percentage by mass: 86-94% of water-gas combined atomized stainless steel powder, 0.05-4% of one or more powders of silver nitrate, copper nitrate, zinc nitrate or silver acetate, copper acetate, zinc acetate, 2.9-10% of ethanol, and 0.5-3% of titanate coupling agent.

6. The method for preparing an antibacterial stainless steel feedstock for in-situ preparation of antibacterial components according to claim 1, characterized in that: The polymer adhesive comprises the following components in percentage by mass: 80-88% of polyoxymethylene, 4-10% of high-density polyethylene, 2-8% of ethylene-vinyl acetate copolymer, 1.8-5% of solid paraffin, 0.1-2.6% of surfactant and 0.2-0.5% of antioxidant.

7. The method for preparing an antibacterial stainless steel feedstock for in-situ preparation of antibacterial components according to claim 6, characterized in that: The surfactant is one or more combinations of stearic acid, pentaerythritol stearate, silver stearate, copper stearate and zinc stearate.

8. The method for preparing an antibacterial stainless steel feedstock for in-situ preparation of antibacterial components according to claim 6, characterized in that: The antioxidant is one or more combinations of AO-3, AO-4, AO-14, AO-15, AO-43 and AO-46.

9. The method for preparing an antibacterial stainless steel feedstock for in-situ preparation of antibacterial components according to claim 1, characterized in that: The mass ratio of the polymer binder to the water-gas atomized stainless steel powder is (7-11):(89-93).

10. The method for preparing an antibacterial stainless steel feedstock for in-situ preparation of antibacterial components according to claim 1, characterized in that: In step S4, the A3 and the water vapor atomized stainless steel powder are mixed in a mixer, and the mixing process parameters are: the rotor speed is 30-40 rpm, the mixing temperature is 180-190° C., and the heating is stopped after mixing for 60-90 minutes.

11. The method for preparing an antibacterial stainless steel feedstock for in-situ preparation of antibacterial components according to claims 1 to 10, wherein an antibacterial stainless steel cutting tool is prepared, characterized in that: The preparation of antibacterial stainless steel cutting tools comprises the following steps: B1. Injection: Add the antibacterial stainless steel feed material into an injection machine, and the injection machine injects the antibacterial stainless steel feed material into the cutting tool mold cavity, and demolds to obtain a cutting tool injection green body, the injection temperature is 190° C., and the mold temperature is 95° C.; B2, degreasing: the injection green body is subjected to oxalic acid catalytic degreasing treatment to form a degreasing body, the degreasing environment temperature is controlled to be 135°C, the acid passing time is 8h, and the acid feeding speed is: 9g / min; B3, sintering: sintering the degreased blank to form a sintered blank; the sintering temperature is 1320°C, the holding time is 8h, the sintering atmosphere is N2, the partial pressure is 10kPa, and the blank is cooled with the furnace; B4. Heat treatment: heat treatment of the sintered blank; 1000°C for 30 min, quenching with 10% salt water, and then tempering at 200°C; B5. Sharpening: sharpening the sintered blank after the heat treatment to obtain an antibacterial stainless steel cutting tool.

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