A mixture for improving lubricity of metal powder and use thereof

Abstract

The application relates to the technical field of metal powder processing, in particular to a mixed agent for improving lubricity of metal powder and application thereof, wherein the mixed agent comprises an additive A, an additive B, an additive C, an additive D, an additive E and an additive F. The mixed agent provided by the application can provide sustained and excellent lubrication for metal powder from low temperature to high temperature through synergistic effect of various additives with different molecular weights and types, can make the metal powder more uniform during processing, can reduce friction during processing, and can reduce energy consumption. The metal powder obtained by the method can be used for later production to obtain high-performance products with uniform density, high mechanical properties and few defects. In addition, the mixed agent provided by the application is suitable for various metal powders, so that the application has wide application prospects in many industries such as aerospace, automobile manufacturing and electronic equipment.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of metal powder processing, and particularly relates to a mixed agent for improving lubricity of metal powder and application thereof. BACKGROUND

[0002] In the field of metal processing, metal powder processing technology, especially metal injection molding and powder metallurgy, has become a key technical means for manufacturing high-performance parts. Metal injection molding can realize near-net-shape forming of complex-shaped parts, and powder metallurgy has unique advantages in mass production of high-precision and high-performance parts. However, the characteristics of metal powder itself, such as high surface energy and inter-particle friction, make it face many challenges in the processing process.

[0003] Traditional metal powder lubricating additives have obvious limitations in dealing with these challenges. Many common single-component lubricants, such as simple fatty acid lubricants, have certain lubricating effect at low temperatures, but their lubricating performance decreases rapidly as the processing temperature rises, which cannot meet the needs of metal powder in high-temperature processing. For example, in some processes involving high-temperature sintering or injection molding, such lubricants are easily decomposed or volatilized during the high-temperature plasticizing stage, resulting in lubrication failure, which in turn causes metal powder aggregation, and may cause oxidation between uncoated metal powders due to mutual friction, thereby causing combustion, which is extremely dangerous and also causes mold wear to increase. In addition, low-molecular-weight single-component binders may also cause the product to contain a large number of porous structures during the later metal powder debinding process due to their own evaporation and vaporization, which greatly reduces the performance of the product.

[0004] In the prior art, there are also means for enhancing the lubricity of metal powder by introducing high-molecular-weight binders to coat the metal powder. However, in actual operation, due to the small size of the metal powder particles and the increase in the overall surface area, more high-molecular-weight binders are needed. Ultimately, due to the large amount of high-molecular-weight binders that cannot uniformly coat the large number of fine metal particles, the flowability of the metal powder is reduced, and the performance of the product is ultimately reduced due to the non-uniform density.

[0005] Therefore, according to the related technology in the above, it is urgent to develop a mixed agent for improving the lubricity of metal powder and application thereof. SUMMARY

[0006] Therefore, according to the related technology in the above, it is urgent to develop a mixed agent for improving the lubricity of metal powder and application thereof.

[0007] Based on the above purpose, the present application provides a mixed agent for improving the lubricity of metal powder and application thereof.

[0008] A mixture for improving lubricity of metal powder, the mixture comprising the following mass parts of raw materials: additive A 2-5 parts, additive B 2-4 parts, additive C 3-3.5 parts, additive D 5-7.5 parts, additive E 30-40 parts, additive F 50-60 parts;

[0009] The additive A is prepared from pentaerythritol stearate and oxidized polyethylene wax;

[0010] The additive B is a low molecular weight binder;

[0011] The additive C is prepared from a low molecular weight binder and a medium molecular weight binder;

[0012] The additive D is a medium molecular weight binder;

[0013] The additive E is prepared from a medium molecular weight binder and a high molecular weight binder;

[0014] The additive F is a high molecular weight binder.

[0015] Preferably, the mass ratio of pentaerythritol stearate and oxidized polyethylene wax in the additive A is 2.8-3.3:1.8-2.3.

[0016] Preferably, the low molecular weight binder is any one or more of stearic acid, zinc stearate, ethylene bis-stearamide, paraffin wax, basf wax and polyethylene wax.

[0017] Preferably, the mass ratio of the low molecular weight binder and the medium molecular weight binder in the additive C is 1.5-2:2.8-3.3.

[0018] Preferably, the medium molecular weight binder is any one or more of butadiene rubber, cis-butadiene rubber, styrene-butadiene rubber, isoprene rubber and chloroprene rubber.

[0019] Preferably, the mass ratio of the medium molecular weight binder and the high molecular weight binder in the additive E is 12-17:24-29.

[0020] Preferably, the high molecular weight binder is any one or more of polyoxymethylene, ethylene-vinyl acetate copolymer, polypropylene and polyethylene.

[0021] Use of a mixture for improving lubricity of metal powder, the use comprising the following steps:

[0022] Step S1. heating the metal powder to be processed to 50-70℃ for preheating for 18-22 min to obtain a mixture 1;

[0023] Step S2. Add Additive A to the mixture 1, and stir at 50-70℃ until the Additive A is melted to obtain a mixture 2;

[0024] Step S3. Add Additive B to the mixture 2, and heat and mix at 69-75℃ for 15-30min to obtain a mixture 3;

[0025] Step S4. Add Additive C to the mixture 3, and heat and mix at 140-150℃ for 15-30min to obtain a mixture 4;

[0026] Step S5. Add Additive D to the mixture 4, and heat and mix at 150-160℃ for 15-30min to obtain a mixture 5;

[0027] Step S6. Add Additive E to the mixture 5, and heat and mix at 160-170℃ for 15-30min to obtain a mixture 6;

[0028] Step S7. Add Additive F to the mixture 6, and heat and mix at 170-180℃ for 15-30min to obtain the high lubricity metal powder.

[0029] Preferably, the metal powder to be processed includes any one of titanium-based metal powder, iron-based metal powder, copper-based metal powder, nickel-based metal powder, cobalt-based metal powder and tungsten-based metal powder.

[0030] Preferably, the titanium-based metal includes titanium powder and titanium alloy powder, which is any one or several of Ti-6Al-4V alloy powder, TA15 titanium alloy powder, Ti-2Al-Nb alloy powder, TiAl alloy powder, Ti-6Al-2Sn-4Zr-2Mo alloy powder, Ti-3Al-2.5V alloy powder and MT-Ti31 titanium alloy powder;

[0031] The iron-based metal powder includes iron powder and iron alloy powder, which is any one or several of silicon-iron powder, chromium-iron powder, manganese-silicon alloy powder, tungsten-nickel-iron alloy powder, niobium-iron alloy powder, iron-cobalt-copper alloy powder, boron-iron powder, iron-silicon-aluminum alloy powder and nickel-iron alloy powder;

[0032] The copper-based metal powder includes copper powder and copper alloy powder, which is any one or several of H62 brass powder, HPb59-1 lead brass powder, tin bronze powder, lead bronze powder, beryllium bronze powder, B10 cupronickel powder and zinc cupronickel powder;

[0033] The nickel-based metal powder includes nickel powder and nickel alloy powder, which is any one or several of nickel-chromium alloy powder, nickel-copper alloy powder, nickel-iron alloy powder, nickel-molybdenum alloy powder, nickel-cobalt alloy powder and nickel-titanium alloy powder;

[0034] The cobalt-based metal powder is cobalt powder and cobalt alloy powder, and the cobalt alloy powder is any one or several of cobalt-chromium alloy powder, cobalt-tungsten alloy powder, cobalt-molybdenum-chromium alloy powder and nickel-cobalt alloy powder;

[0035] The tungsten-based metal powder is tungsten powder and tungsten alloy powder, and the tungsten alloy powder is any one or several of tungsten carbide powder, tungsten-chromium alloy powder, tungsten-molybdenum alloy powder, tungsten-molybdenum-chromium alloy powder, tungsten-copper alloy powder, tungsten-nickel-iron alloy powder and cobalt-chromium-tungsten alloy powder.

[0036] The beneficial effects of the present application are:

[0037] The mixed agent provided by the present application can provide sustained and excellent lubrication for metal powder from low temperature to high temperature through the synergistic effect of a plurality of different molecular weight and type additives, so that the metal powder is mixed more uniformly in the processing process, while reducing the friction in the processing process, reducing energy consumption, and the metal powder obtained by the method is used for later production to obtain high-performance products with uniform density, high mechanical properties and few defects. In addition, the mixed agent provided by the present application is suitable for a plurality of metal powders, which makes the present application have wide application prospects in many industries such as aerospace, automobile manufacturing and electronic equipment. BRIEF DESCRIPTION OF DRAWINGS

[0038] In order to more clearly illustrate the technical solutions in the present application or prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description only illustrate the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0039] Figure 1 It is a magnified view of the high-lubricity metal powder obtained in Example 1 of the present application;

[0040] Figure 2 It is a magnified view of the high-lubricity metal powder obtained in Comparative Example 4 of the present application;

[0041] Figure 3 It is a magnified view of the high-lubricity metal powder obtained in Comparative Example 5 of the present application. DETAILED DESCRIPTION

[0042] In order to make the purpose, technical scheme and advantages of the present application more clear, the following will further illustrate the present application in combination with specific embodiments.

[0043] Preparation Example 1: a preparation method of an additive A, comprising the following steps:

[0044] Mix 2.8 g of pentaerythritol stearate and 1.8 g of oxidized polyoxyethylene wax to obtain an additive A.

[0045] Preparation Example 2: A method of preparing an additive A, comprising the steps of:

[0046] Mix 2.9 g of pentaerythritol stearate and 1.9 g of oxidized polyoxyethylene wax to obtain an additive A.

[0047] Preparation Example 3: A method of preparing an additive A, comprising the steps of:

[0048] Mix 3 g of pentaerythritol stearate and 2 g of oxidized polyoxyethylene wax to obtain an additive A.

[0049] Preparation Example 4: A method of preparing an additive A, comprising the steps of:

[0050] Mix 3.1 g of pentaerythritol stearate and 2.1 g of oxidized polyoxyethylene wax to obtain an additive A.

[0051] Preparation Example 5: A method of preparing an additive A, comprising the steps of:

[0052] Mix 3.2 g of pentaerythritol stearate and 2.2 g of oxidized polyoxyethylene wax to obtain an additive A.

[0053] Preparation Example 6: A method of preparing an additive A, comprising the steps of:

[0054] Mix 3.3 g of pentaerythritol stearate and 2.3 g of oxidized polyoxyethylene wax to obtain an additive A.

[0055] Preparation Example 7: A method of preparing an additive C, comprising the steps of:

[0056] Mix 1.5 g of stearic acid and 2.8 g of butadiene rubber to obtain an additive C.

[0057] Preparation Example 8: A method of preparing an additive C, comprising the steps of:

[0058] Mix 1.6 g of zinc stearate and 2.9 g of cis-butadiene rubber to obtain an additive C.

[0059] Preparation Example 9: A method of preparing an additive C, comprising the steps of:

[0060] Mix 1.7 g of ethylene bis-stearamide and 3 g of butadiene-styrene rubber to obtain an additive C.

[0061] Preparation Example 10: A method of preparing an additive C, comprising the steps of:

[0062] Mix 1.8 g of paraffin wax and 3.1 g of isoprene rubber to obtain additive C.

[0063] Preparation Example 11: A method of preparing an additive C, comprising the steps of:

[0064] Mix 1.9 g of BASF wax and 3.2 g of chloroprene rubber to obtain additive C.

[0065] Preparation Example 12: A method of preparing an additive C, comprising the steps of:

[0066] Mix 2 g of polyethylene wax and 3.3 g of chloroprene rubber to obtain additive C.

[0067] Preparation Example 13: A method of preparing an additive E, comprising the steps of:

[0068] Mix 12 g of butadiene rubber and 24 g of polyformaldehyde to obtain additive E.

[0069] Preparation Example 14: A method of preparing an additive E, comprising the steps of:

[0070] Mix 13 g of cis-butadiene rubber and 25 g of ethylene-vinyl acetate copolymer to obtain additive E.

[0071] Preparation Example 15: A method of preparing an additive E, comprising the steps of:

[0072] Mix 14 g of styrene-butadiene rubber and 26 g of polypropylene to obtain additive E.

[0073] Preparation Example 16: A method of preparing an additive E, comprising the steps of:

[0074] Mix 15 g of isoprene rubber and 27 g of polyethylene to obtain additive E.

[0075] Preparation Example 17: A method of preparing an additive E, comprising the steps of:

[0076] Mix 16 g of chloroprene rubber and 28 g of polyethylene to obtain additive E.

[0077] Preparation Example 18: A method of preparing an additive E, comprising the steps of:

[0078] Mix 17 g of butadiene rubber and 29 g of polyformaldehyde to obtain additive E.

[0079] Preparation Example 19: A method of preparing a mixture for improving lubricity of metal powder, comprising the steps of:

[0080] A mixture for improving lubricity of metal powder is obtained by using 2 g of the additive A obtained in Preparation Example 1, using 2 g of stearic acid as the additive B, using 3 g of the additive C obtained in Preparation Example 7 as the additive C, using 5 g of butadiene rubber as the additive D, using 30 g of the additive E obtained in Preparation Example 13 as the additive E, and using 50 g of polyformaldehyde as the additive F.

[0081] Preparation Example 20: A method for preparing a mixture for improving lubricity of metal powder, comprising the following steps:

[0082] A mixture for improving lubricity of metal powder is obtained by using 3 g of the additive A obtained in Preparation Example 2, using 3 g of zinc stearate as the additive B, using 3.2 g of the additive C obtained in Preparation Example 8 as the additive C, using 6 g of butadiene rubber as the additive D, using 33 g of the additive E obtained in Preparation Example 14 as the additive E, and using 53 g of ethylene-vinyl acetate copolymer as the additive F.

[0083] Preparation Example 21: A method for preparing a mixture for improving lubricity of metal powder, comprising the following steps:

[0084] A mixture for improving lubricity of metal powder is obtained by using 4 g of the additive A obtained in Preparation Example 3, using 3.5 g of ethylene bis-stearamide as the additive B, using 3.4 g of the additive C obtained in Preparation Example 9 as the additive C, using 7 g of butadiene rubber as the additive D, using 37 g of the additive E obtained in Preparation Example 15 as the additive E, and using 57 g of polypropylene as the additive F.

[0085] Preparation Example 22: A method for preparing a mixture for improving lubricity of metal powder, comprising the following steps:

[0086] A mixture for improving lubricity of metal powder is obtained by using 5 g of the additive A obtained in Preparation Example 4, using 4 g of paraffin wax as the additive B, using 3.5 g of the additive C obtained in Preparation Example 10 as the additive C, using 7.5 g of isoprene rubber as the additive D, using 40 g of the additive E obtained in Preparation Example 16 as the additive E, and using 60 g of polyethylene as the additive F.

[0087] Example 1: Application of a mixture for improving lubricity of metal powder, comprising the following steps:

[0088] S1. mixing titanium powder, Ti-6Al-4V alloy powder, TA15 titanium alloy powder, Ti-2Al-Nb alloy powder, TiAl alloy powder, Ti-6Al-2Sn-4Zr-2Mo alloy powder, Ti-3Al-2.5V alloy powder and MT-Ti31 titanium alloy powder to obtain metal powder to be processed;

[0089] S2. heating the metal powder to be processed to 50℃ for preheating for 18 min to obtain a mixture 1;

[0090] S2. Add all the additive A in Preparation Example 19 to 4140 g of the mixture 1, and stir at 50°C until the additive A is melted to obtain a mixture 2;

[0091] S3. Add all the additive B in Preparation Example 19 to the mixture 2, and heat and mix for 15 min at 69°C to obtain a mixture 3;

[0092] S4. Add all the additive C in Preparation Example 19 to the mixture 3, and heat and mix for 15 min at 140°C to obtain a mixture 4;

[0093] S5. Add all the additive D in Preparation Example 19 to the mixture 4, and heat and mix for 15 min at 150°C to obtain a mixture 5;

[0094] S6. Add all the additive E in Preparation Example 19 to the mixture 5, and heat and mix for 15 min at 160°C to obtain a mixture 6;

[0095] S7. Add all the additive F in Preparation Example 19 to the mixture 6, and heat and mix for 15 min at 170°C to obtain a high-lubricity metal powder.

[0096] Example 2: Application of a mixture for improving the lubricity of a metal powder, comprising the following steps:

[0097] S1. Mix iron powder, ferrosilicon powder, ferrochrome powder, manganese-silicon alloy powder, tungsten-nickel-iron alloy powder, niobium-iron alloy powder, iron-cobalt-copper alloy powder, boron-iron powder, iron-silicon-aluminum alloy powder, and nickel-iron alloy powder to obtain a metal powder to be processed;

[0098] S2. Heat the metal powder to be processed to 54°C for preheating for 19 min to obtain a mixture 1;

[0099] S2. Add all the additive A in Preparation Example 20 to 4392 g of the mixture 1, and stir at 54°C until the additive A is melted to obtain a mixture 2;

[0100] S3. Add all the additive B in Preparation Example 20 to the mixture 2, and heat and mix for 18 min at 70°C to obtain a mixture 3;

[0101] S4. Add all the additive C in Preparation Example 20 to the mixture 3, and heat and mix for 18 min at 142°C to obtain a mixture 4;

[0102] S5. Add all the additive D in Preparation Example 20 to the mixture 4, and heat and mix for 18 min at 152°C to obtain a mixture 5;

[0103] S6. Add all the additive E in Preparation Example 20 to the mixture 5, heat and mix at 162℃ for 18min to obtain a mixture 6;

[0104] S7. Add all the additive F in Preparation Example 20 to the mixture 6, heat and mix at 172℃ for 18min to obtain a high lubricity metal powder.

[0105] Example 3: Application of a mixture for improving lubricity of metal powder, comprising the following steps:

[0106] S1. Mix copper powder, H62 brass powder, HPb59-1 lead brass powder, tin bronze powder, lead bronze powder, beryllium bronze powder, B10 cupronickel powder and zinc cupronickel powder to obtain a metal powder to be processed;

[0107] S2. Heat the metal powder to be processed to 58℃ for 20min to obtain a mixture 1;

[0108] S2. Add all the additive A in Preparation Example 21 to 4644g of the mixture 1, stir at 58℃ until the additive A is melted to obtain a mixture 2;

[0109] S3. Add all the additive B in Preparation Example 21 to the mixture 2, heat and mix at 71℃ for 21min to obtain a mixture 3;

[0110] S4. Add all the additive C in Preparation Example 21 to the mixture 3, heat and mix at 144℃ for 21min to obtain a mixture 4;

[0111] S5. Add all the additive D in Preparation Example 21 to the mixture 4, heat and mix at 154℃ for 21min to obtain a mixture 5;

[0112] S6. Add all the additive E in Preparation Example 21 to the mixture 5, heat and mix at 164℃ for 21min to obtain a mixture 6;

[0113] S7. Add all the additive F in Preparation Example 21 to the mixture 6, heat and mix at 174℃ for 21min to obtain a high lubricity metal powder.

[0114] Example 4: Application of a mixture for improving lubricity of metal powder, comprising the following steps:

[0115] S1. Mix nickel powder, nickel-chromium alloy powder, nickel-copper alloy powder, nickel-iron alloy powder, nickel-molybdenum alloy powder, nickel-cobalt alloy powder and nickel-titanium alloy powder to obtain a metal powder to be processed;

[0116] S2. Heat the metal powder to be processed to 62℃ for 21min to obtain a mixture 1;

[0117] S2. Add all the additive A in Preparation Example 22 to 4896 g of the mixture 1, and stir at 62°C until the additive A is melted to obtain a mixture 2;

[0118] S3. Add all the additive B in Preparation Example 22 to the mixture 2, and heat and mix for 24 min at 72°C to obtain a mixture 3;

[0119] S4. Add all the additive C in Preparation Example 22 to the mixture 3, and heat and mix for 24 min at 146°C to obtain a mixture 4;

[0120] S5. Add all the additive D in Preparation Example 22 to the mixture 4, and heat and mix for 24 min at 156°C to obtain a mixture 5;

[0121] S6. Add all the additive E in Preparation Example 22 to the mixture 5, and heat and mix for 24 min at 166°C to obtain a mixture 6;

[0122] S7. Add all the additive F in Preparation Example 22 to the mixture 6, and heat and mix for 24 min at 176°C to obtain a high-lubricity metal powder.

[0123] Example 5: Application of a mixture for improving the lubricity of a metal powder, comprising the following steps:

[0124] S1. Mix cobalt powder, cobalt-chromium alloy powder, cobalt-tungsten alloy powder, cobalt-molybdenum-chromium alloy powder, and nickel-cobalt alloy powder to obtain a metal powder to be processed;

[0125] S2. Heat the metal powder to be processed to 66°C and preheat for 21 min to obtain a mixture 1;

[0126] S2. Add all the additive A in Preparation Example 20 to 5148 g of the mixture 1, and stir at 66°C until the additive A is melted to obtain a mixture 2;

[0127] S3. Add all the additive B in Preparation Example 20 to the mixture 2, and heat and mix for 27 min at 74°C to obtain a mixture 3;

[0128] S4. Add all the additive C in Preparation Example 20 to the mixture 3, and heat and mix for 27 min at 148°C to obtain a mixture 4;

[0129] S5. Add all the additive D in Preparation Example 20 to the mixture 4, and heat and mix for 27 min at 158°C to obtain a mixture 5;

[0130] S6. Add all the additive E in Preparation Example 21 to the mixture 5, heat and mix at 168℃ for 27min to obtain a mixture 6;

[0131] S7. Add all the additive F in Preparation Example 20 to the mixture 6, heat and mix at 178℃ for 27min to obtain a high lubricity metal powder.

[0132] Example 6: Application of a mixture for improving the lubricity of metal powder, comprising the following steps:

[0133] S1. Mix tungsten powder, tungsten carbide powder, tungsten chromium alloy powder, tungsten molybdenum alloy powder, tungsten rhenium alloy powder, tungsten copper alloy powder, tungsten nickel iron alloy powder and cobalt chromium tungsten alloy powder to obtain a metal powder to be processed;

[0134] S2. Heat the metal powder to be processed to 70℃ for preheating for 22min to obtain a mixture 1;

[0135] S2. Add all the additive A in Preparation Example 19 to 5400g of the mixture 1, stir at 70℃ until the additive A is melted to obtain a mixture 2;

[0136] S3. Add all the additive B in Preparation Example 19 to the mixture 2, heat and mix at 75℃ for 30min to obtain a mixture 3;

[0137] S4. Add all the additive C in Preparation Example 19 to the mixture 3, heat and mix at 150℃ for 30min to obtain a mixture 4;

[0138] S5. Add all the additive D in Preparation Example 19 to the mixture 4, heat and mix at 160℃ for 30min to obtain a mixture 5;

[0139] S6. Add all the additive E in Preparation Example 19 to the mixture 5, heat and mix at 170℃ for 30min to obtain a mixture 6;

[0140] S7. Add all the additive F in Preparation Example 19 to the mixture 6, heat and mix at 180℃ for 30min to obtain a high lubricity metal powder.

[0141] Comparative Example 1:

[0142] This comparative example is the same as Example 1 except that no additive C is added, and the rest of the steps and parameters are the same. The high lubricity metal powder is obtained finally.

[0143] Comparative Example 2:

[0144] The comparative example is compared with example 1 only without adding additive E, and the rest of the steps and parameters are the same. The comparative example will not be repeated here. Finally, a high-lubricity metal powder is obtained.

[0145] Comparative example 3:

[0146] The comparative example is compared with example 1 only by adjusting the amount of “additive C” from “3g” to “30g”, and the rest of the steps and parameters are the same. The comparative example will not be repeated here. Finally, a high-lubricity metal powder is obtained.

[0147] Comparative example 4:

[0148] The comparative example is compared with example 1 only by adjusting the amount of “mixing material 1” from “4140g” to “414g”, and the rest of the steps and parameters are the same. The comparative example will not be repeated here. Finally, a high-lubricity metal powder is obtained.

[0149] Comparative example 5:

[0150] The comparative example is compared with example 1 only by adjusting the amount of “mixing material 1” from “4140g” to “41400g”, and the rest of the steps and parameters are the same. The comparative example will not be repeated here. Finally, a high-lubricity metal powder is obtained.

[0151] Comparative example 6: Application of a mixing agent for improving the lubricity of metal powder, comprising the following steps:

[0152] S1. Mix titanium powder, Ti-6Al-4V alloy powder, TA15 titanium alloy powder, Ti-2Al-Nb alloy powder, TiAl alloy powder, Ti-6Al-2Sn-4Zr-2Mo alloy powder, Ti-3Al-2.5V alloy powder and MT-Ti31 titanium alloy powder to obtain a metal powder to be processed;

[0153] S2. Heat the metal powder to be processed to 50℃ for 18min preheating to obtain mixing material 1;

[0154] S2. Add all the additive A in preparation example 19 to 4140g of mixing material 1, and stir at 50℃ until the additive A is melted to obtain mixing material 2;

[0155] S3. Add all the additive C in preparation example 19 to the mixing material 2, and heat and mix at 69℃ for 15min to obtain mixing material 3;

[0156] S4. Add all the additive B in preparation example 19 to the mixing material 3, and heat and mix at 140℃ for 15min to obtain mixing material 4;

[0157] S5. Add all the additive D in preparation example 19 to the mixing material 4, and heat and mix at 150℃ for 15min to obtain mixing material 5;

[0158] S6. To the mixed material 5, all the additive E in Preparation Example 19 is added, heated and mixed at 160℃ for 15min to obtain mixed material 6;

[0159] S7. To the mixed material 6, all the additive F in Preparation Example 19 is added, heated and mixed at 170℃ for 15min to obtain high lubricity metal powder.

[0160] Comparative Example 7: Application of a mixed agent for improving the lubricity of metal powder, comprising the following steps:

[0161] S1. Titanium powder, Ti-6Al-4V alloy powder, TA15 titanium alloy powder, Ti-2Al-Nb alloy powder, TiAl alloy powder, Ti-6Al-2Sn-4Zr-2Mo alloy powder, Ti-3Al-2.5V alloy powder and MT-Ti31 titanium alloy powder are mixed to obtain a metal powder to be processed;

[0162] S2. The metal powder to be processed is heated to 50℃ and preheated for 18min to obtain mixed material 1;

[0163] S2. To 4140g of mixed material 1, all the additive A in Preparation Example 19 is added, stirred at 50℃ until the additive A is melted to obtain mixed material 2;

[0164] S3. To the mixed material 2, all the additive B in Preparation Example 19 is added, heated and mixed at 69℃ for 15min to obtain mixed material 3;

[0165] S4. To the mixed material 3, all the additive C in Preparation Example 19 is added, heated and mixed at 140℃ for 15min to obtain mixed material 4;

[0166] S5. To the mixed material 4, all the additive E in Preparation Example 19 is added, heated and mixed at 150℃ for 15min to obtain mixed material 5;

[0167] S6. To the mixed material 5, all the additive D in Preparation Example 19 is added, heated and mixed at 160℃ for 15min to obtain mixed material 6;

[0168] S7. To the mixed material 6, all the additive F in Preparation Example 19 is added, heated and mixed at 170℃ for 15min to obtain high lubricity metal powder.

[0169] Performance test:

[0170] I. Lubricity test:

[0171] 1. Coefficient of friction measurement: using pin-on-disk friction and wear testing machine, the metal powder in Example 1-Example 6 and Comparative Example 1-Comparative Example 7 of the present application is made into cylindrical samples, and relative sliding is carried out with a metal disk at 25°C, the friction force during the friction process is recorded, and the coefficient of friction is calculated.

[0172] 2. Injection pressure test (for metal injection molding process): using the metal injection molding test equipment, the metal powder in Example 1-Example 6 and Comparative Example 1-Comparative Example 7 of the present application is used for injection molding operation respectively, the injection speed and mold temperature are kept constant, and the pressure required during injection is recorded.

[0173] II. Mixing uniformity test:

[0174] Microstructure observation: the metal powder in Example 1, Comparative Example 4 and Comparative Example 5 is observed by scanning electron microscope (SEM), the surface morphology and distribution of metal powder particles are observed under microscope, it can be clearly seen that after the treatment of the mixing agent of the present application, the additive is uniformly coated on the surface of the metal powder particles, and there is no obvious agglomeration phenomenon, as shown in Figure 1 , the surface of the metal powder particles is smooth and wrapped in a layer of uniform substance, while Figure 2 , the metal powder in Comparative Example 4 is in an enlarged view, the amount of metal powder is too small to mix uniformly, Figure 3 , the metal powder in Comparative Example 5 is in an enlarged view, the amount of metal powder is too large to mix uniformly, it can be obviously found that there are uncoated areas and agglomeration phenomenon on the surface of the metal powder particles in the comparative example, which shows that the amount of mixing agent and the treatment process of the present application can effectively realize the uniform mixing of metal powder and additive, and lay a good foundation for improving the product quality.

[0175] III. Product density uniformity test

[0176] Archimedes drainage method to measure density: select the metal powder in Example 1-Example 6 and Comparative Example 1-Comparative Example 7 of the present application to make cylindrical samples by powder metallurgy process, use Archimedes drainage method to measure the density respectively, the measurement process is strictly according to the standard operation process, to ensure the accuracy of the measurement results, calculate the average value of the density of these samples.

[0177] IV. Mechanical property test:

[0178] 1. Tensile strength test: The metal powders obtained in Examples 1-6 and Comparative Examples 1-7 were prepared into metal tensile samples according to ASTM E8 standard, and a universal material testing machine was used to test the tensile strength of each sample. During the test, a constant tensile rate was applied until the sample broke, the maximum tensile force at the time of breakage was recorded, and the tensile strength was calculated.

[0179] 2. Hardness test: The metal powder products obtained in Examples 1-6 and Comparative Examples 1-7 were tested for hardness using a Rockwell hardness tester or a Brinell hardness tester. The appropriate hardness testing method and indenter were selected according to the material and size of the product. Multiple test points were selected on the surface of the sample, the hardness values were measured and averaged.

[0180] The results are shown in Table 1 below:

[0181] Table 1

[0182] Item coefficient of friction injection pressure density tensile strength Rockwell hardness Example 1 0.12 71 MPa 7.8 g / cm 3 ]] 360 MPa 28 HRC Example 2 0.15 70.2 MPa 7.45 g / cm 3 ]] 350.4 MPa 25 HRC Example 3 0.13 68 MPa 7.9 g / cm 3 ]] 381.3 MPa 28 HRC Example 4 0.14 68.4 MPa 7.65 g / cm 3 ]] 362.5 MPa 29 HRC Example 5 0.16 73.5 MPa 8.0 g / cm 3 ]] 368 MPa 24 HRC Example 6 0.18 60.8 MPa 7.55 g / cm 3 ]] 353.2 MPa 27 HRC Comparative Example 1 0.24 77.6 MPa 6.6 g / cm 3 ]]> 324 MPa 22.3 HRC Comparative Example 2 0.26 82.8 MPa 5.8 g / cm 3 ]] 304 MPa 20.8 HRC Comparative Example 3 0.25 82 MPa 5.9 g / cm 3 ]]> 311 MPa 21.3 HRC Comparative Example 4 0.28 99.75 MPa 4.45 g / cm 3 ]]> 293.7 MPa 17.1 HRC Comparative Example 5 0.3 90 MPa 4.65 g / cm 3 ]]> 295.4 MPa 17.5 HRC Comparative Example 6 0.2 74.8 MPa 6.75 g / cm 3 ]]> 338.4 MPa 22.5 HRC Comparative Example 7 0.24 80.75 MPa 6.5 g / cm 3 ]] 321 MPa 22.1 HRC

[0183] Data analysis:

[0184] As can be seen from Table 1, the metal powder treated with the mixing agent of the present application has a significantly reduced coefficient of friction, effectively reducing the frictional force during the processing of the metal powder, reducing energy consumption, and improving the service life and processing efficiency of the processing equipment. The injection pressure of the metal powder treated with the mixing agent of the present application is significantly reduced, which fully demonstrates the excellent lubricating effect of the mixing agent of the present application in the metal injection molding process, which can significantly improve the flowability of the metal powder, making it easier to fill the mold cavity, and improving the success rate of molding and product quality. The uniformity of the density of the product treated with the mixing agent of the present application is significantly improved, which means that the density difference inside the product is smaller and the structure is more uniform, thereby improving the mechanical properties and reliability of the product. The tensile strength of the sample treated with the mixing agent of the present application is significantly improved, which is due to the fact that the mixing agent of the present application improves the lubricity and mixing uniformity of the metal powder, making the internal structure of the product more dense and the bonding between the metal powders more firm, thereby effectively improving the tensile strength of the product. The Rockwell hardness value of the metal powder product treated with the mixing agent of the present application is significantly higher, which indicates that the mixing agent of the present application can improve the hardness performance of the metal powder product, making it more suitable for use in some application scenarios with higher hardness requirements.

[0185] The mixed agent provided by the application can provide sustained and excellent lubrication for metal powder from low temperature to high temperature through the synergistic effect of various additives with different molecular weights and types. In the initial stage of metal powder processing, low molecular weight additives such as stearic acid and pentaerythritol stearate can quickly play a lubricating role, reduce the friction between metal powders, and enable metal powders to be mixed more smoothly. Before the high molecular weight reaches the melting point and even completely wraps the powder, the heat generated by the increased friction of metal powder at high temperature is reduced, avoiding the local high temperature that causes the high molecular weight binder to crack. The second wrapping by the medium molecular weight and high molecular weight binder can avoid the problem of oxidation or even burning caused by incomplete and uneven wrapping of the high molecular weight binder due to friction between metal powders. Finally, the powder is completely coated with the binder, has good dispersibility, and thus has good fluidity, effectively reducing the wear between metal powder and processing equipment, improving the service life of the processing equipment, and significantly reducing the injection pressure in the metal injection molding process, greatly improving the processing convenience and economy.

[0186] The mixed agent provided by the application increases the lubricity of metal powder during processing, enables metal powder to be mixed more uniformly, and enables the pressure distribution during forming to be more uniform, thereby significantly improving the density uniformity of the final product. In powder metallurgy products, the density uniformity of the product is improved, thereby comprehensively improving the mechanical properties such as strength and hardness of the product. In addition, good lubricity reduces the frictional force during processing, thereby reducing energy consumption. In the mixing, forming and other processing links of metal powder, production efficiency can be significantly improved, production costs can be reduced, and market competitiveness of enterprises can be enhanced. At the same time, since the processing process is smoother, the precision and stability requirements of the processing equipment are relatively reduced, which is beneficial to reducing equipment procurement and maintenance costs of enterprises.

[0187] The mixed agent provided by the application is suitable for various metal powders, including titanium-based metal powder, iron-based metal powder, copper-based metal powder, nickel-based metal powder, cobalt-based metal powder and tungsten-based metal powder, and various alloy powders thereof. Whether it is titanium alloy powder with high activity or common iron powder, copper powder, etc., the mixed agent of the application can effectively improve the lubricity thereof. This makes the application have wide application prospects in many industries such as aerospace, automobile manufacturing and electronic equipment. For example, in the manufacturing of titanium alloy parts in the aerospace field, the use of the mixed agent can improve the formability and density of titanium alloy powder, thereby improving the mechanical properties of the parts and meeting the requirements of high strength and high reliability of aerospace parts.

[0188] Those skilled in the art should understand that the above discussion of any embodiment is merely exemplary in nature and is not intended to imply that the present application is limited to these examples; any of the above embodiments or technical features among different embodiments can be combined, and steps can be implemented in any order, under the idea of the present application, and there are many other changes of different aspects of the present application as described above, which are not provided in details for the sake of brevity.

[0189] The present application is intended to cover all such alternatives, modifications, and variations as come within the scope of the broadest possible interpretation of the appended claims. Accordingly, any and all such alternations, modifications, equivalents, improvements and the like are intended to be encompassed by the present application.

Claims

1. An additive for improving lubricity of a metal powder, characterized by comprising: The mixed agent comprises the following mass parts of raw materials: 2-5 parts of additive A, 2-4 parts of additive B, 3-3.5 parts of additive C, 5-7.5 parts of additive D, 30-40 parts of additive E, and 50-60 parts of additive F; The additive A is prepared from pentaerythritol stearate and oxidized polyethylene wax; The additive B is a low molecular weight binder; The additive C is prepared from a low molecular weight binder and a medium molecular weight binder; The additive D is a medium molecular weight binder; The additive E is prepared from a medium molecular weight binder and a high molecular weight binder; The additive F is a high molecular weight binder; The mass ratio of pentaerythritol stearate to oxidized polyethylene wax in the additive A is 2.8-3.3:1.8-2.3; The low molecular weight binder is any one or more of stearic acid, zinc stearate, ethylene bis-stearamide, paraffin wax, basf wax, and polyethylene wax; The mass ratio of the low molecular weight binder to the medium molecular weight binder in the additive C is 1.5-2:2.8-3.3; The medium molecular weight binder is any one or more of butadiene rubber, cis-butadiene rubber, styrene-butadiene rubber, isoprene rubber, and chloroprene rubber; The mass ratio of the medium molecular weight binder to the high molecular weight binder in the additive E is 12-17:24-29; The high molecular weight binder is any one or more of polyformaldehyde, ethylene-vinyl acetate copolymer, polypropylene, and polyethylene.

2. Use of the mixture for improving lubricity of metal powder according to claim 1, characterized in that, The application comprises the following steps: Step S1. Heating the metal powder to be processed to 50-70℃ for preheating for 18-22 min to obtain mixed material 1; Step S2. Adding the additive A to the mixed material 1, and stirring at 50-70℃ until the additive A is melted to obtain mixed material 2; Step S3. Adding the additive B to the mixed material 2, and heating and mixing at 69-75℃ for 15-30 min to obtain mixed material 3; Step S4. Adding the additive C to the mixed material 3, and heating and mixing at 140-150℃ for 15-30 min to obtain mixed material 4; Step S5. Adding the additive D to the mixed material 4, and heating and mixing at 150-160℃ for 15-30 min to obtain mixed material 5; Step S6. Adding the additive E to the mixed material 5, and heating and mixing at 160-170℃ for 15-30 min to obtain mixed material 6; Step S7. Adding the additive F to the mixed material 6, and heating and mixing at 170-180℃ for 15-30 min to obtain the metal powder with high lubricity; The mass ratio of the metal powder to be processed to the additive A in step S2 is 4140-5400:2-5.

3. The use of the mixture for improving the lubricity of metal powder according to claim 2, characterized in that, The metal powder to be processed comprises any one of titanium-based metal powder, iron-based metal powder, copper-based metal powder, nickel-based metal powder, cobalt-based metal powder, and tungsten-based metal powder.

4. The use of the mixture for improving the lubricity of metal powder according to claim 3, characterized in that, The titanium-based metal includes titanium powder and titanium alloy powder, and the titanium alloy powder is any one or more of Ti-6Al-4V alloy powder, TA15 titanium alloy powder, Ti-2Al-Nb alloy powder, TiAl alloy powder, Ti-6Al-2Sn-4Zr-2Mo alloy powder, Ti-3Al-2.5V alloy powder and MT-Ti31 titanium alloy powder; The iron-based metal powder includes iron powder and iron alloy powder, and the iron alloy powder is any one or more of silicon-iron powder, chromium-iron powder, manganese-silicon alloy powder, tungsten-nickel-iron alloy powder, niobium-iron alloy powder, iron-cobalt-copper alloy powder, boron-iron powder, iron-silicon-aluminum alloy powder and nickel-iron alloy powder; The copper-based metal powder includes copper powder and copper alloy powder, and the copper alloy powder is any one or more of H62 brass powder, HPb59-1 lead brass powder, tin bronze powder, lead bronze powder, beryllium bronze powder, B10 cupronickel powder and zinc cupronickel powder; The nickel-based metal powder includes nickel powder and nickel alloy powder, and the nickel alloy powder is any one or more of nickel-chromium alloy powder, nickel-copper alloy powder, nickel-iron alloy powder, nickel-molybdenum alloy powder, nickel-cobalt alloy powder and nickel-titanium alloy powder; The cobalt-based metal powder is cobalt powder and cobalt alloy powder, and the cobalt alloy powder is any one or more of cobalt-chromium alloy powder, cobalt-tungsten alloy powder, cobalt-chromium-molybdenum alloy powder and nickel-cobalt alloy powder; The tungsten-based metal powder is tungsten powder and tungsten alloy powder, and the tungsten alloy powder is any one or more of tungsten carbide powder, tungsten-chromium alloy powder, tungsten-molybdenum alloy powder, tungsten-molybdenum alloy powder, tungsten-copper alloy powder, tungsten-nickel-iron alloy powder, cobalt-chromium-tungsten alloy powder.

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