CN114836711B - Metal surface hardening method - Google Patents
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- CN114836711B CN114836711B CN202210504585.5A CN202210504585A CN114836711B CN 114836711 B CN114836711 B CN 114836711B CN 202210504585 A CN202210504585 A CN 202210504585A CN 114836711 B CN114836711 B CN 114836711B
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- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C8/00—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
- C23C8/60—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using solids, e.g. powders, pastes
- C23C8/62—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using solids, e.g. powders, pastes only one element being applied
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Abstract
The invention relates to the technical field of metal surface treatment, in particular to a metal surface hardening method, which comprises the steps of carrying out rust removal and oil removal on the metal surface by using oxalic acid solution, loading the metal and an infiltration agent into a graphite die, embedding the metal into the infiltration agent, sealing the graphite die and putting the graphite die into a resistance furnace for heating and infiltration, firstly heating to 600-620 ℃ for one section, keeping the temperature for 1-2 hours, then heating to 950-960 ℃ for two sections, keeping the temperature for 3-5 hours, cooling the furnace to room temperature, then quenching at 600-650 ℃, and tempering at 220-240 ℃.
Description
Technical Field
The invention relates to the technical field of metal surface treatment, in particular to a metal surface hardening method.
Background
It is often necessary to harden the surface of the metal during the metal smelting process to improve wear resistance, corrosion resistance, heat resistance, and fatigue strength. Commonly used surface hardening methods are: carburizing and quenching, nitriding, surface quenching, and the like. The boronizing is also an effective surface strengthening method for various metal materials, the surface hardness and the wear and corrosion resistance of the metal materials can be greatly improved, the existing boronizing hardening method for the metal surfaces can be divided into a solid method, a liquid method, a gas method, a plasma method, a paste method and the like, the most used method for the metal materials at present is a solid method (powder embedding method), the penetration speed of boron is lower than the carburization and nitridation speeds because the radius of boron atoms is far greater than that of carbon atoms and nitrogen atoms, the penetration layer obtained by the existing boronizing method for the solid method is low in density, many in hole defects, the hardness, the wear resistance and the like of the penetration layer are difficult to meet the use requirements.
Disclosure of Invention
The purpose of the invention is as follows: in order to solve the technical problems, the invention provides a metal surface hardening method.
The adopted technical scheme is as follows:
a method of metal case hardening comprising the steps of:
s1: vacuum packaging a boron donor, a rare earth compound and a filler in a closed tank according to a certain mass ratio, placing the tank on a ball mill for ball milling and powder mixing at room temperature, adding a penetrating agent into the tank after the powder mixing is finished, then performing vacuum packaging, placing the tank on the ball mill for continuous ball milling, and obtaining the penetrating agent after the ball milling is finished;
s2: carrying out rust and oil removal on the metal surface by using an oxalic acid solution;
s3: putting metal and a penetrating agent into a graphite mold, embedding the metal into the penetrating agent, sealing the graphite mold, putting the graphite mold into a resistance furnace, heating and infiltrating, firstly heating to 600-620 ℃ for one section, preserving heat for 1-2h, then heating to 950-960 ℃ for another section, preserving heat for 3-5h, cooling the furnace to room temperature, quenching at 600-650 ℃, and tempering at 220-240 ℃.
Further, the boron donor comprises borax and boric acid.
Further, the mass ratio of the borax to the boric acid is 8-10:1.
further, the rare earth compounds include rare earth oxides, rare earth chlorides, and rare earth aluminates.
Further, the rare earth oxide is any one or combination of more of lanthanum oxide, cerium oxide, praseodymium oxide and yttrium oxide;
the rare earth chloride is any one or combination of a plurality of lanthanum chloride, cerium chloride, praseodymium chloride and yttrium chloride;
the rare earth aluminate is any one or combination of lanthanum aluminate, gadolinium aluminate, neodymium aluminate and yttrium aluminate.
Further, the rare earth compound comprises lanthanum oxide, lanthanum chloride and lanthanum aluminate, wherein the mass ratio of the lanthanum oxide to the lanthanum chloride to the lanthanum aluminate is 2-4:2-4:1.
further, the preparation method of the lanthanum aluminate comprises the following steps:
uniformly mixing aluminum nitrate, potassium hydroxide and water, adding lanthanum nitrate, reacting for 3-5h, filtering out the obtained precipitate, drying, and calcining for 8-10h at 900-950 ℃.
Further, the filler is silicon carbide and graphite.
Further, the energizer is ammonium chloride and sodium fluoride.
Further, the mass ratio of the boron donor, the rare earth compound, the filling agent and the catalytic penetration agent is 20-40:5-10:50-60:10-20.
The invention has the beneficial effects that:
the invention provides a metal surface hardening method, which takes borax and boric acid as boron supply agents, has high boron potential and strong boronizing capacity, and adds rare earth compounds to improve the diffusion speed and range of boron elements, thereby improving the thickness of a boronizing layer and improving the hardness and the wear resistance of the metal surface.
Drawings
FIG. 1 is a microstructure of a metal after surface hardening treatment in example 1 of the present invention.
Detailed Description
The examples, in which specific conditions are not specified, were conducted under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products available commercially.
Example 1:
a method of hardening a metal surface:
3000g of borax, 300g of boric acid, 400g of lanthanum oxide, 400g of lanthanum chloride, 100g of lanthanum aluminate, 2000g of silicon carbide and 3000g of graphite are vacuum-packaged in a closed tank body, and are placed on a ball mill at room temperature for ball milling and powder mixing, wherein the ball-to-material ratio is 50:1, after ball milling for 4 hours, adding 500g of ammonium chloride and 650g of sodium fluoride as accelerant into a tank body, then carrying out vacuum packaging, placing the tank body on a ball mill for continuous ball milling, after ball milling for 8 hours, obtaining the penetrant, cleaning, removing rust and oil on the surface of TC4 titanium alloy by using 10wt% oxalic acid solution, washing and drying for later use, placing the TC4 titanium alloy and the penetrant into a graphite mold, embedding the TC4 titanium alloy into the penetrant, sealing the graphite mold, placing the graphite mold into a resistance furnace for heating and infiltration, firstly heating to 620 ℃ at the speed of 15 ℃/min, carrying out heat preservation for 2 hours, then heating to 950 ℃ at the speed of 5 ℃/min for two-stage heating, carrying out heat preservation for 4 hours, cooling the furnace to room temperature, then carrying out quenching at 630 ℃, and carrying out tempering treatment at 240 ℃.
The preparation method of the lanthanum aluminate comprises the following steps:
213g of aluminum nitrate, 112g of potassium hydroxide and 2L of water are uniformly mixed, 325g of lanthanum nitrate is added, the mixture is stirred and mixed for reaction for 5 hours, the obtained precipitate is filtered out, and the precipitate is dried and calcined for 10 hours at 930 ℃.
Example 2:
a method of hardening a metal surface:
3000g of borax, 500g of boric acid, 400g of lanthanum oxide, 400g of lanthanum chloride, 200g of lanthanum aluminate, 2000g of silicon carbide and 3000g of graphite are packaged in a closed tank in vacuum, and the sealed tank is placed on a ball mill at room temperature for ball milling and powder mixing, wherein the ball material ratio is 50:1, after ball milling for 4 hours, adding 500g of ammonium chloride and 650g of sodium fluoride as accelerant into a tank body, then carrying out vacuum packaging, placing the tank body on a ball mill for continuous ball milling, after ball milling for 8 hours, obtaining the penetrant, cleaning, removing rust and oil on the surface of TC4 titanium alloy by using 10wt% oxalic acid solution, washing and drying for later use, placing the TC4 titanium alloy and the penetrant into a graphite mold, embedding the TC4 titanium alloy into the penetrant, sealing the graphite mold, placing the graphite mold into a resistance furnace for heating and infiltration, firstly heating to 620 ℃ at the speed of 20 ℃/min, carrying out heat preservation for 2 hours, then heating to 960 ℃ at the speed of 5 ℃/min for two-stage heating, carrying out heat preservation for 5 hours, cooling the furnace to room temperature, then carrying out quenching at 650 ℃, and carrying out tempering treatment at 240 ℃.
The preparation method of the lanthanum aluminate comprises the following steps:
213g of aluminum nitrate, 112g of potassium hydroxide and 2L of water are uniformly mixed, 325g of lanthanum nitrate is added, the mixture is stirred, mixed and reacted for 5 hours, the obtained precipitate is filtered out, and the precipitate is dried and calcined for 10 hours at 950 ℃.
Example 3:
a method of hardening a metal surface:
3000g of borax, 300g of boric acid, 400g of lanthanum oxide, 400g of lanthanum chloride, 200g of lanthanum aluminate, 2000g of silicon carbide and 3000g of graphite are vacuum-packaged in a closed tank body, and are placed on a ball mill at room temperature for ball milling and powder mixing, wherein the ball-to-material ratio is 50:1, after ball milling for 4 hours, adding 500g of ammonium chloride and 650g of sodium fluoride as accelerant into a tank body, then carrying out vacuum packaging, placing the tank body on a ball mill for continuous ball milling, after ball milling for 8 hours, obtaining an impregnation agent, cleaning, removing rust and oil on the surface of TC4 titanium alloy by using 10wt% oxalic acid solution, washing and drying for later use, placing the TC4 titanium alloy and the impregnation agent into a graphite mold, embedding the TC4 titanium alloy into the impregnation agent, sealing the graphite mold, placing the graphite mold into a resistance furnace for heating and impregnation, firstly heating to 600 ℃ at the speed of 10 ℃/min, carrying out heat preservation for 1 hour, then heating to 950 ℃ at the speed of 3 ℃/min for two-stage heating, carrying out heat preservation for 3 hours, cooling the furnace to room temperature, then carrying out quenching at 600 ℃, and carrying out tempering treatment at 220 ℃.
The preparation method of the lanthanum aluminate comprises the following steps:
213g of aluminum nitrate, 112g of potassium hydroxide and 2L of water are uniformly mixed, 325g of lanthanum nitrate is added, the mixture is stirred and mixed for reaction for 3 hours, the obtained precipitate is filtered out, and the precipitate is dried and calcined for 8 hours at 900 ℃.
Example 4:
a method of hardening a metal surface:
3000g of borax, 300g of boric acid, 400g of lanthanum oxide, 400g of lanthanum chloride, 100g of lanthanum aluminate, 2500g of silicon carbide and 3000g of graphite are vacuum-packaged in a closed tank, and are placed on a ball mill at room temperature for ball milling and powder mixing, wherein the ball-material ratio is 50:1, after ball milling for 4 hours, adding 500g of ammonium chloride and 650g of sodium fluoride as accelerant into a tank body, then carrying out vacuum packaging, placing the tank body on a ball mill for continuous ball milling, after ball milling for 8 hours, obtaining the penetrant, cleaning, removing rust and oil on the surface of TC4 titanium alloy by using 10wt% oxalic acid solution, washing and drying for later use, placing the TC4 titanium alloy and the penetrant into a graphite mold, embedding the TC4 titanium alloy into the penetrant, sealing the graphite mold, placing the graphite mold into a resistance furnace for heating and infiltration, firstly heating to 620 ℃ at the speed of 10 ℃/min, carrying out heat preservation for 1 hour, then heating to 950 ℃ at the speed of 5 ℃/min for two-stage heating, carrying out heat preservation for 5 hours, cooling the furnace to room temperature, then carrying out quenching at 600 ℃, and carrying out tempering treatment at 240 ℃.
The preparation method of the lanthanum aluminate comprises the following steps:
213g of aluminum nitrate, 112g of potassium hydroxide and 2L of water are uniformly mixed, 325g of lanthanum nitrate is added, the mixture is stirred and mixed for reaction for 3 hours, the obtained precipitate is filtered out, and the precipitate is dried and calcined for 8 hours at 950 ℃.
Example 5:
a method of hardening a metal surface:
3000g of borax, 300g of boric acid, 400g of lanthanum oxide, 400g of lanthanum chloride, 100g of lanthanum aluminate, 2000g of silicon carbide and 3000g of graphite are vacuum-packaged in a closed tank body, and are placed on a ball mill at room temperature for ball milling and powder mixing, wherein the ball-to-material ratio is 50:1, after ball milling for 4 hours, adding 500g of ammonium chloride and 650g of sodium fluoride into a tank body as an energizer, then carrying out vacuum packaging, placing on a ball mill for continuous ball milling for 8 hours to obtain the energizer, cleaning, derusting and deoiling the surface of TC4 titanium alloy by using 10wt% of oxalic acid solution, then washing and drying for standby, placing the TC4 titanium alloy and the energizer into a graphite mold, embedding the TC4 titanium alloy into the energizer, sealing the graphite mold and placing the graphite mold into a resistance furnace for heating and infiltrating, firstly heating to 600 ℃ at the speed of 20 ℃/min, keeping the temperature for 2 hours, then heating to 960 ℃ at the speed of 3 ℃/min for two stages, keeping the temperature for 3 hours, cooling the furnace to room temperature, then quenching at 650 ℃, and tempering at 220 ℃.
The preparation method of the lanthanum aluminate comprises the following steps:
213g of aluminum nitrate, 112g of potassium hydroxide and 2L of water are uniformly mixed, 325g of lanthanum nitrate is added, the mixture is stirred and mixed for reaction for 5 hours, the obtained precipitate is filtered out, and the precipitate is dried and calcined for 10 hours at 900 ℃.
Comparative example 1:
essentially the same as example 1, except that lanthanum oxide, lanthanum chloride, lanthanum aluminate were not added.
Comparative example 2:
essentially the same as example 1, except that lanthanum aluminate was not added.
Comparative example 3:
essentially the same as in example 1, except that no ammonium chloride was added.
Comparative example 4:
essentially the same as in example 1, except that no sodium fluoride was added.
And (4) performance testing:
the TC4 titanium alloy subjected to hardening treatment in the examples 1-5 and the comparative examples 1-4 of the invention is used as a sample, the depth of a boronized layer of the sample is measured according to JB/T7709-95, the microhardness of the boronized layer is measured by an HV-1000 type microhardness meter, an abrasion resistance test is carried out on an M-200 type abrasion tester under the room temperature condition, a friction pair material is GCr15, the hardness is 62HRC, the rotating speeds of an upper wheel and a lower wheel are respectively 200r/min and 180r/min, weights are loaded 30kg and weighed after 200min, and the test results are shown in the following table 1:
table 1:
as can be seen from the above Table 1, the hardness of the metal surface treated by the method of the present invention is increased, and the wear resistance is improved, and the addition of the rare earth compound has a positive effect on increasing the depth of the boriding layer, and improving the hardness and wear resistance.
The above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.
Claims (7)
1. A method of hardening a metal surface, comprising the steps of:
s1: vacuum packaging a boron donor, a rare earth compound and a filler in a sealed tank according to a certain mass ratio, placing the sealed tank on a ball mill at room temperature for ball milling and mixing, adding a penetration promoter into the tank after the powder mixing is finished, then carrying out vacuum packaging, placing the sealed tank on the ball mill for continuous ball milling, and obtaining the penetration promoter after the ball milling is finished;
s2: carrying out rust and oil removal on the metal surface by using an oxalic acid solution;
s3: putting metal and a penetrating agent into a graphite mold, embedding the metal into the penetrating agent, sealing the graphite mold, putting the graphite mold into a resistance furnace, heating and infiltrating, firstly heating to 600-620 ℃ for the first time, preserving heat for 1-2h, then heating to 950-960 ℃ for the second time, preserving heat for 3-5h, cooling the furnace to room temperature, quenching at 600-650 ℃, and tempering at 220-240 ℃;
the rare earth compound comprises lanthanum oxide, lanthanum chloride and lanthanum aluminate, wherein the mass ratio of the lanthanum oxide to the lanthanum chloride to the lanthanum aluminate is (2-4): 2-4:1;
the preparation method of the lanthanum aluminate comprises the following steps:
uniformly mixing aluminum nitrate, potassium hydroxide and water, adding lanthanum nitrate, reacting for 3-5h, filtering out the obtained precipitate, drying, and calcining for 8-10h at 900-950 ℃.
2. The method of hardening a metal surface of claim 1, wherein the boron donor agent comprises borax and boric acid.
3. The metal surface hardening method of claim 2, wherein a mass ratio of the borax to the boric acid is from 8 to 10:1.
4. the method of metal hardfacing of claim 1, wherein the rare earth compound comprises a rare earth oxide, a rare earth chloride, and a rare earth aluminate.
5. The method of metal hardfacing of claim 1, wherein the filler is silicon carbide and graphite.
6. The method of metal facing hardening of claim 1, wherein the infiltrant is ammonium chloride and sodium fluoride.
7. The method of hardening a metal surface according to claim 1, wherein the mass ratio of the boron donor, the rare earth compound, the filler, and the catalyst is 20 to 40:5-10:50-60:10-20.
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| CN115872776B (en) * | 2022-11-07 | 2023-06-23 | 航天特种材料及工艺技术研究所 | Surface gradient hardening method of nano heat insulation material |
| CN117947375B (en) * | 2024-03-26 | 2024-05-31 | 西安理工大学 | Boronizing agent for nickel-based alloy surface boronizing and boronizing method |
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| CN1314828C (en) * | 2004-11-23 | 2007-05-09 | 江苏工业学院 | Method and apparatus for DC electric field accelerating solid powder boriding |
| CN101135038B (en) * | 2006-08-31 | 2010-05-12 | 宝山钢铁股份有限公司 | Boronizing agent and method of use thereof |
| CN101608295B (en) * | 2009-07-17 | 2012-09-05 | 东北大学 | Use method of powder penetrating agent for titanium alloy surface boronizing |
| CN102071394A (en) * | 2009-11-20 | 2011-05-25 | 缪建良 | Process method for metal surface boronisation |
| CN103014604B (en) * | 2013-01-05 | 2015-10-28 | 江苏大学 | The titanium alloy surface modification solid powder boronisation agent and boronizing method of oozing is urged based on lanthanum trioxide |
| CN103966544B (en) * | 2013-01-30 | 2016-09-21 | 沈阳鼓风机集团齿轮压缩机有限公司 | The surface boronizing agent of a kind of Ni based high-temperature alloy and using method thereof |
| CN104911535B (en) * | 2015-06-26 | 2017-06-09 | 中南大学 | A kind of titanium surface solid boronising boriding medium and boriding process |
| CN106367713A (en) * | 2016-09-12 | 2017-02-01 | 江苏大学 | Titanium alloy surface salt-bath boronizing agent and boronizing method thereof |
| CN106702316A (en) * | 2017-01-11 | 2017-05-24 | 王军平 | Liquid rare earth boron-vanadium composite cementation co-crystallizing method for low-carbon steel |
| CN108950470A (en) * | 2018-07-24 | 2018-12-07 | 东北大学 | A method of being able to maintain the surface boronizing of titanium alloy high intensity |
| CN110965017A (en) * | 2019-12-12 | 2020-04-07 | 南京航空航天大学 | Method for preparing co-permeation layer on surface of TC4 titanium alloy by using boro-carburizing method |
| CN111705293B (en) * | 2020-06-30 | 2022-02-22 | 广东正信硬质材料技术研发有限公司 | Hard alloy surface boronizing method |
| CN113005394B (en) * | 2021-02-22 | 2021-12-07 | 山东农业大学 | J55 steel pipe processing method based on rare earth catalytic carbonitriding |
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