阅读说明：本技术 一种热处理方法及热处理工装 (Heat treatment method and heat treatment tool ) 是由 张登坡 郭全海 于 2021-01-19 设计创作，主要内容包括：本发明提出一种热处理方法,包括：渗碳炉空炉预热,在空炉预热的同时将空气与甲醇通入,空炉预热后将经过渗碳炉外预热的工件放入渗碳炉的加热室中,持续通入空气,待加热室温度降低后提高加热室的温度,加热室的温度提高后停止向加热室内通入空气,同时通入富化气,通入富化气一段时间后降低富化气的通入量,并通入氨气并保持一段时间后,依次进行淬火、清洗、回火和冷却,工装冷却后完成热处理。本发明的有益效果在于：通过在热处理过程中空炉阶段对渗碳炉的加热室进行气氛的置换,通过通入平衡空气将渗碳炉加热室炉内气氛中的碳势降低,减少炉内气氛中残留的活性炭含量,避免在工件表面形成固态分子碳黑。(The invention provides a heat treatment method, which comprises the following steps: preheating an empty carburizing furnace, introducing air and methanol while preheating the empty carburizing furnace, placing a workpiece preheated outside the carburizing furnace into a heating chamber of the carburizing furnace after the empty carburizing furnace is preheated, continuously introducing the air, increasing the temperature of the heating chamber after the temperature of the heating chamber is reduced, stopping introducing the air into the heating chamber after the temperature of the heating chamber is increased, simultaneously introducing rich gas, reducing the introduction amount of the rich gas after introducing the rich gas for a period of time, introducing ammonia gas and keeping for a period of time, sequentially quenching, cleaning, tempering and cooling, and finishing heat treatment after the tool is cooled. The invention has the beneficial effects that: the heating chamber of the carburizing furnace is subjected to atmosphere replacement in the empty furnace stage in the heat treatment process, and the carbon potential in the atmosphere in the heating chamber of the carburizing furnace is reduced by introducing balance air, so that the content of residual activated carbon in the atmosphere in the furnace is reduced, and the formation of solid molecular carbon black on the surface of a workpiece is avoided.)

1. A heat treatment method, characterized by comprising the steps of:

s1, raising the temperature of a heating chamber of a carburizing furnace to 915 +/-15 ℃, introducing air and methanol into the heating chamber of the carburizing furnace, and keeping for a first preset time to control the atmospheric carbon potential in the heating chamber of the carburizing furnace to be 0.2-0.4%;

s2, placing the tool into a carburizing furnace heating chamber, continuously introducing air and methanol into the carburizing furnace heating chamber, keeping the atmospheric carbon potential in the carburizing furnace heating chamber between 0.2% and 0.4%, waiting for the temperature of the carburizing furnace heating chamber to be reduced to 780 +/-30 ℃, and then raising the temperature of the carburizing furnace heating chamber to 840 +/-10 ℃;

s3, stopping introducing air into the heating chamber of the carburizing furnace when the temperature of the heating chamber of the carburizing furnace is raised to 840 +/-10 ℃, introducing the enriched gas into the heating chamber of the carburizing furnace, controlling the atmosphere carbon potential in the heating chamber of the carburizing furnace to be 0.7-0.8%, and continuing for a second preset time;

s4, controlling the atmospheric carbon potential in the heating chamber of the carburizing furnace to be 0.7-0.8 percent, reducing the introduction amount of the enriched gas after the atmospheric carbon potential in the heating chamber of the carburizing furnace reaches the second preset time, introducing ammonia gas into the heating chamber of the carburizing furnace, controlling the atmospheric carbon potential in the heating chamber of the carburizing furnace to be 0.6-0.7 percent, and keeping the third preset time,

s5, controlling the atmosphere carbon potential in the carburizing furnace heating chamber to be 0.6% -0.7%, introducing ammonia gas into the carburizing furnace heating chamber, keeping for a third preset time, sequentially quenching, cleaning, tempering and cooling the tool, and completing heat treatment after the tool is cooled.

2. The heat treatment method according to claim 1, characterized in that: in step S1, the air introduction speed is 15L-30L/min, the methanol introduction speed is 30mL-50mL/min, and the first preset time is 30min-90 min.

3. The heat treatment method according to claim 1, characterized in that: in step S2, the tool is preheated before being placed in the heating chamber of the carburizing furnace.

4. The heat treatment method according to claim 3, characterized in that: the preheating parameter of the tool is heating for 30-90 min at the temperature of 300-450 ℃.

5. The heat treatment method according to claim 1, characterized in that: in step S3, the enriched gas is propane, the flowing speed of the propane is 4L-8L/min, and the second preset time is 60min-90 min.

6. The heat treatment method according to claim 1, characterized in that: in step S4, the enriched gas is propane, the introduction amount of propane is reduced to 2L-6L/min, the introduction amount of ammonia is 1L-3L/min, and the third preset time is 30min-60 min.

7. The heat treatment method according to claim 5 or 6, characterized in that: the amount of propane introduced in step S4 was smaller than the amount of propane introduced in step S3.

8. The heat treatment method according to claim 1, characterized in that: in step S3 and step S4, methanol is continuously introduced into the heating chamber of the carburizing furnace at a rate of 30mL-50 mL/min.

9. A heat treatment tool, comprising: bearing shelf and a plurality of bar, it is a plurality of the bar interval is hung on the bearing shelf, its characterized in that: heat treatment is carried out by the heat treatment method according to any one of claims 1 to 8.

10. The heat treatment tool according to claim 9, wherein: be provided with the screens baffle on the bearing shelf, be provided with a plurality of equidistance spaced bayonets on the screens baffle, the bar passes through the bayonet socket is fixed to be set up on the bearing shelf.

Technical Field

The invention belongs to the technical field of heat treatment, and particularly relates to a heat treatment method and a heat treatment tool.

Background

At present, a U-shaped tooth product belongs to a metal part with a small size, the process before heat treatment is finished after punch forming, the surface of the product is not a machined surface but a rough surface with large roughness, carbon in a heat treatment atmosphere is easily accumulated in the surface quality state in the heat treatment process, once the carbon black is accumulated into solid carbon black on the surface of a workpiece, the carburization of a local area is organized, and the uniformity of the carburization depth and the quenching hardening depth is influenced.

Such quality problems always plague the improvement of the heat treatment quality of products, and further endanger the personal safety of drivers and passengers and the safety of vehicles.

Disclosure of Invention

The embodiment of the invention provides a heat treatment method, and mainly aims to provide a heat treatment method for reducing the content of residual activated carbon in the atmosphere in a heat treatment furnace by introducing air into a heating chamber of a carburizing furnace so as to avoid carbon black from being formed on the surface of a tool after heat treatment.

In order to achieve the above purpose, the embodiment of the invention adopts the following technical scheme:

a method of heat treatment comprising the steps of:

s1, raising the temperature of a heating chamber of a carburizing furnace to 915 +/-15 ℃, introducing air and methanol into the heating chamber of the carburizing furnace, and keeping for a first preset time to control the atmospheric carbon potential in the heating chamber of the carburizing furnace to be 0.2-0.4%;

s2, placing the tool into a carburizing furnace heating chamber, continuously introducing air and methanol into the carburizing furnace heating chamber, keeping the atmospheric carbon potential in the carburizing furnace heating chamber between 0.2% and 0.4%, waiting for the temperature of the carburizing furnace heating chamber to be reduced to 780 +/-30 ℃, and then raising the temperature of the carburizing furnace heating chamber to 840 +/-10 ℃;

s3, stopping introducing air into the heating chamber of the carburizing furnace when the temperature of the heating chamber of the carburizing furnace is raised to 840 +/-10 ℃, introducing the enriched gas into the heating chamber of the carburizing furnace, controlling the atmosphere carbon potential in the heating chamber of the carburizing furnace to be 0.7-0.8%, and continuing for a second preset time;

s4, when the atmosphere carbon potential in the heating chamber of the carburizing furnace reaches 0.7% -0.8%, after the second preset time, reducing the introduction amount of the enriched gas, introducing ammonia gas into the heating chamber of the carburizing furnace, controlling the atmosphere carbon potential in the heating chamber of the carburizing furnace at 0.6% -0.7%, keeping the third preset time,

s5, controlling the atmosphere carbon potential in the carburizing furnace heating chamber to be 0.6% -0.7%, introducing ammonia gas into the carburizing furnace heating chamber, keeping for a third preset time, sequentially quenching, cleaning, tempering and cooling the tool, and completing heat treatment after the tool is cooled.

In the embodiment of the invention, in the step S1, the air introducing speed is 15L-30L/min, the methanol introducing speed is 30mL-50mL/min, and the first preset time is 30min-90 min.

In the embodiment of the invention, in step S2, the tool is preheated before being placed in the heating chamber of the carburizing furnace, the air introducing speed is 15L-30L/min, and the methanol introducing speed is 30mL-50 mL/min.

In the embodiment of the invention, the preheating parameter of the tool is heating at the temperature of 300-450 ℃ for 30-90 min.

In the embodiment of the invention, in step S3, the enriched gas is propane, the introduction amount of propane is 4L to 8L/min, and the second preset time is 60min to 90 min.

In the embodiment of the invention, in step S4, the enriched gas is propane, the amount of propane introduced is reduced to 2L to 6L/min, the amount of ammonia introduced is 1L to 3L/min, and the third preset time is 30min to 60 min.

In the embodiment of the present invention, the amount of propane introduced in step S4 is smaller than the amount of propane introduced in step S3.

In the embodiment of the present invention, in steps S3 and S4, methanol is continuously introduced into the heating chamber of the carburizing furnace at a rate of 30 mL/min to 50 mL/min.

Another object of the present invention is to provide a heat treatment tool, comprising: the heat treatment method comprises a bearing shelf and a plurality of bar stocks, wherein the bar stocks are hung on the bearing shelf at intervals and are subjected to heat treatment by adopting the heat treatment method.

In the embodiment of the invention, the bearing shelf is provided with a clamping baffle plate, the clamping baffle plate is provided with a plurality of bayonets at equal intervals, and the bar stock is fixedly arranged on the bearing shelf through the bayonets.

The invention has the following effective effects:

1. in the heat treatment process, the atmosphere is replaced in the stage of preheating the empty furnace, the carbon potential in the furnace atmosphere is reduced by introducing balance air into the heating chamber of the carburizing furnace, the content of the residual activated carbon in the furnace atmosphere is reduced, and the problem of poor heat treatment effect caused by the formation of solid molecular carbon black on the surface of a workpiece subjected to heat treatment in the prior art is solved.

2. Set up the screens baffle on the bearing shelf, the equidistant a plurality of bayonets that set up of screens baffle, fix in the bayonet socket of screens baffle through the bar that will treat thermal treatment, make the equidistant spaced of bar fix on the bearing shelf, keep the interval between the bar on the bearing shelf, simultaneously after sending the bearing shelf into the carburizing furnace heating chamber in the thermal treatment stove, prevent that the bar from leading to rocking because of being heated and taking place high temperature creep, deformation overproof such as extrusion deformation is scrapped even, and the binding face appears between the bar, lead to the inhomogeneous problem of carburization layer degree of depth.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a schematic view of a heat treatment method according to an embodiment of the present invention;

FIG. 2 is a line drawing showing the temperature inside the heating chamber of the carburizing furnace in the embodiment of the invention;

FIG. 3 is a schematic view of a heat treatment tool according to an embodiment of the present invention;

FIG. 4 is a schematic view of a heat treatment tool retaining plate according to an embodiment of the present invention;

in the above figures: 1. a load bearing shelf; 101. mounting holes; 2. long bar stock; 3. a short clamp stop; 301. a first bayonet; 4. a clamping baffle is added; 401. a second bayonet; 5. a long clamping position baffle; 501. a third bayonet; 6. short bar stock; 7. and (5) producing the product.

Detailed Description

The invention is described in detail below by way of exemplary embodiments. It should be understood, however, that elements, structures and features of one embodiment may be beneficially incorporated in other embodiments without further recitation.

In the description of the present invention, it is to be understood that the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of description and simplicity of description, and do not indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and thus, are not to be construed as limiting the present invention.

The terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

According to the embodiment of the invention, the heat treatment tool is subjected to heat treatment, so that the performance of the workpiece to be subjected to heat treatment on the heat treatment tool is improved. Referring to fig. 1, the processing method mainly includes five steps: step one, increasing the temperature of a heating chamber of a carburizing furnace, introducing air and methanol, keeping for a first preset time, and controlling the carbon potential of the atmosphere; secondly, putting the workpiece into a heating chamber of a carburizing furnace, heating the heating chamber of the carburizing furnace, maintaining the atmosphere carbon potential, and increasing the temperature of the heating chamber of the carburizing furnace; thirdly, introducing air, introducing richening gas, controlling the carbon potential of the atmosphere to be reduced, and continuing for a second preset time; fourthly, reducing the introduction amount of the enriched gas, introducing ammonia gas, and keeping the third preset time; and fifthly, quenching, cleaning, tempering and cooling the tool in sequence, and finishing heat treatment after the tool is cooled.

Specifically, in the first step S1, the temperature of the heating chamber of the carburizing furnace needs to be raised to 915 ℃ ± 15 ℃, air and methanol are introduced into the heating chamber of the carburizing furnace, the introduction speed of the air is 15L-30L/min, the introduction speed of the methanol is 30mL-50mL/min, and the temperature is maintained for 30min-90min, so that the atmospheric carbon potential in the heating chamber of the carburizing furnace is controlled to be 0.2% -0.4%.

In the second step S2, before the tool is placed in the heating chamber of the carburizing furnace, preheating is carried out for 30min-90min at the temperature of 300 ℃ to 450 ℃, the preheated workpiece is placed in the heating chamber of the carburizing furnace, air and methanol are continuously introduced into the heating chamber of the carburizing furnace, the introduction speed of the air is 15L-30L/min, the introduction speed of the methanol is 30mL-50mL/min, the temperature of the heating chamber of the carburizing furnace is waited to be reduced to 780 ℃ plus or minus 30 ℃, the atmosphere carbon potential in the heating chamber of the carburizing furnace is kept between 0.2% and 0.4%, and then the temperature of the heating chamber of the carburizing furnace is raised to 840 ℃ plus or minus 10 ℃.

In the third step S3, when the temperature of the heating chamber of the carburizing furnace is raised to 840 +/-10 ℃, stopping introducing air into the heating chamber of the carburizing furnace, introducing the enriched gas, namely propane, into the heating chamber of the carburizing furnace, and continuously introducing methanol, wherein the introducing speed of the propane is 4-8L/min, the introducing speed of the methanol is 30-50 mL/min, and the atmosphere carbon potential in the heating chamber of the carburizing furnace is controlled to be 0.7-0.8% and is kept for 60-90 min.

In a fourth step S4, the carbon potential of the atmosphere in the heating chamber of the carburizing furnace reaches 0.7% -0.8%, the introduction amount of propane is reduced to 2L-6L/min after the carbon potential lasts for 60min-90min, methanol is continuously introduced at the introduction speed of 30mL-50mL/min, ammonia gas is introduced into the heating chamber of the carburizing furnace, the introduction amount of the ammonia gas is 1L-3L/min, the carbon potential of the atmosphere in the heating chamber of the carburizing furnace is controlled to be 0.6% -0.7%, and the carbon potential is kept for 30min-60 min.

In a fifth step S5, controlling the atmosphere carbon potential in the heating chamber of the carburizing furnace to be 0.6-0.7%, keeping for 30-60 min, sequentially quenching, cleaning, tempering and cooling the tool, and finishing heat treatment after cooling the tool.

The tool processed according to the heat treatment method realizes the control of the appearance quality of the tool product after heat treatment, effectively reduces the appearance quality defect of solid carbon black accumulated on the product surface caused by low temperature and high carbon potential and the internal quality defect of uneven seepage layer and uneven depth of a hardening layer caused by the defect, eliminates the risk of early failure of the tool product in the service process, and can improve the fatigue resistance of the product and prolong the service life.

To further illustrate the heat treatment process of the present invention, the following is further described by way of example:

the first embodiment is as follows:

referring to fig. 2, in the first step S1, the temperature of the heating chamber of the carburizing furnace needs to be raised to 930 ℃, air and methanol are introduced into the heating chamber of the carburizing furnace, the air introduction rate is 25L/min, the methanol introduction rate is 40mL/min, and the temperature is maintained for 60min, so that the atmospheric carbon potential in the heating chamber of the carburizing furnace is controlled to be 0.2%.

In the second step S2, before the tool is placed in the heating chamber of the carburizing furnace, the tool is preheated for 60min at a temperature of 350 ℃, the preheated workpiece is placed in the heating chamber of the carburizing furnace, air and methanol are continuously introduced into the heating chamber of the carburizing furnace, the air introduction speed is 25L/min, the methanol introduction speed is 40mL/min, the temperature of the heating chamber of the carburizing furnace is waited to be reduced to 780 ℃, the atmospheric carbon potential in the heating chamber of the carburizing furnace is kept at 0.2%, and then the temperature of the heating chamber of the carburizing furnace is increased to 830 ℃.

In the third step S3, when the temperature of the heating chamber of the carburizing furnace is raised to 830 ℃, the air supply into the heating chamber of the carburizing furnace is stopped, propane is supplied into the heating chamber of the carburizing furnace, methanol is continuously supplied, the supply speed of propane is 7L/min, the supply speed of methanol is 40mL/min, and the atmospheric carbon potential in the heating chamber of the carburizing furnace is controlled to be 0.7% and is kept for 60 min.

In a fourth step S4, the atmospheric carbon potential in the carburizing furnace heating chamber reaches 0.7%, and after the atmospheric carbon potential lasts for 60min, the introduction amount of propane is reduced to 3L/min, methanol is continuously introduced, the introduction rate of methanol is 40mL/min, ammonia gas is introduced into the carburizing furnace heating chamber, the introduction amount of ammonia gas is 2L/min, and the atmospheric carbon potential in the carburizing furnace heating chamber is controlled to be 0.6% and kept for 60 min.

In a fifth step S5, the carbon potential of the atmosphere in the heating chamber of the carburizing furnace is controlled to be 0.6%, and after the atmosphere is maintained for 60min, the tool is sequentially quenched, cleaned, tempered and cooled, and heat treatment is completed after the tool is cooled.

In the quenching process, Daphne Hi-temp Oil A Oil is used, the Oil temperature of the quenching Oil is 140 ℃, the workpiece is put into the quenching Oil for 20min, and the Oil draining time is 20 min.

Heating at 290 deg.C for 160min during tempering, and cooling the workpiece with air cooling after tempering.

The heat treatment method in the embodiment optimizes the atmosphere and medium control of the process, replaces and burns off the residual carbon in the atmosphere, controls and optimizes the flow of the enriched gas in the carburizing process, reduces the generation of newly added carbon black, and has good, uniform and consistent appearance of the whole furnace product without carbon black.

Example two:

in the first step S1, the temperature of the heating chamber of the carburizing furnace needs to be raised to 910 ℃, air and methanol are introduced into the heating chamber of the carburizing furnace, the air introduction rate is 30L/min, the methanol introduction rate is 35mL/min, and the air and methanol introduction rate is maintained for 75min, so that the atmospheric carbon potential in the heating chamber of the carburizing furnace is controlled to be 0.25%.

In a second step S2, before the tool is placed in the heating chamber of the carburizing furnace, preheating the tool at 370 ℃ for 40min, placing the preheated workpiece in the heating chamber of the carburizing furnace, continuously introducing air and methanol into the heating chamber of the carburizing furnace at a speed of 30L/min and 35mL/min, waiting for the temperature of the heating chamber of the carburizing furnace to decrease to 775 ℃, keeping the atmospheric carbon potential in the heating chamber of the carburizing furnace at 0.25%, and then raising the temperature of the heating chamber of the carburizing furnace to 845 ℃.

In the third step S3, when the temperature of the heating chamber of the carburizing furnace is raised to 845 ℃, the air introduction into the heating chamber of the carburizing furnace is stopped, propane is introduced into the heating chamber of the carburizing furnace, methanol is continuously introduced, the propane introduction speed is 6L/min, the methanol introduction speed is 35mL/min, and the atmospheric carbon potential in the heating chamber of the carburizing furnace is controlled to be 0.75% and is continued for 65 min.

In the fourth step S4, the atmospheric carbon potential in the carburizing furnace heating chamber reaches 0.75%, and after the atmospheric carbon potential lasts for 65min, the introduction amount of propane is reduced to 2.5L/min, methanol is continuously introduced, the introduction rate of methanol is 35mL/min, ammonia gas is introduced into the carburizing furnace heating chamber, the introduction amount of ammonia gas is 2.2L/min, and the atmospheric carbon potential in the carburizing furnace heating chamber is controlled to be 0.65% and kept for 70 min.

In a fifth step S5, the atmospheric carbon potential in the heating chamber of the carburizing furnace is controlled to be 0.65%, and after the atmospheric carbon potential is maintained for 75min, the tool is sequentially quenched, cleaned, tempered and cooled, and heat treatment is completed after the tool is cooled.

In the quenching process, Daphne Hi-temp Oil A Oil is used, the Oil temperature of the quenching Oil is 145 ℃, the workpiece is put into the quenching Oil for 25min, and the Oil draining time is 25 min.

Heating at 300 deg.C for 150min during tempering, and cooling the workpiece with air cooling after tempering.

The heat treatment method in the embodiment optimizes the atmosphere and medium control of the process, replaces and burns off the residual carbon in the atmosphere, controls and optimizes the flow of the enriched gas in the carburizing process, reduces the generation of newly added carbon black, and has good, uniform and consistent appearance of the whole furnace product without carbon black.

Example three:

in the first step S1, the temperature of the heating chamber of the carburizing furnace needs to be raised to 901 ℃, air and methanol are introduced into the heating chamber of the carburizing furnace, the air introduction speed is 17L/min, the methanol introduction speed is 39mL/min, and the air and methanol introduction speed is kept for 59min, so that the atmospheric carbon potential in the heating chamber of the carburizing furnace is controlled to be 0.29%.

In the second step S2, before the tool is placed in the heating chamber of the carburizing furnace, the tool is preheated for 49min at a temperature of 378 ℃, the preheated workpiece is placed in the heating chamber of the carburizing furnace, air and methanol are continuously introduced into the heating chamber of the carburizing furnace, the introduction rate of the air is 17L/min, the introduction rate of the methanol is 39mL/min, the temperature of the heating chamber of the carburizing furnace is waited to be reduced to 799 ℃, the atmospheric carbon potential in the heating chamber of the carburizing furnace is kept at 0.29%, and then the temperature of the heating chamber of the carburizing furnace is increased to 839 ℃.

In the third step S3, when the temperature of the heating chamber of the carburizing furnace is raised to 839 ℃, the air introduction into the heating chamber of the carburizing furnace is stopped, the enriched gas, i.e., propane, is introduced into the heating chamber of the carburizing furnace, the methanol is continuously introduced, the propane introduction speed is 5.7L/min, the methanol introduction speed is 39mL/min, and the atmospheric carbon potential in the heating chamber of the carburizing furnace is controlled to be 0.73% and is continued for 79 min.

In the fourth step S4, the atmospheric carbon potential in the carburizing furnace heating chamber reaches 0.73%, and after 79min, the flow rate of propane is reduced to 2.9L/min, methanol is continuously fed in at a flow rate of 39mL/min, ammonia gas is fed into the carburizing furnace heating chamber at a flow rate of 1.9L/min, and the atmospheric carbon potential in the carburizing furnace heating chamber is controlled to 0.61% and maintained for 41 min.

In a fifth step S5, the carbon potential of the atmosphere in the heating chamber of the carburizing furnace is controlled to be 0.61%, and is maintained for 41min, and then the tool is sequentially quenched, cleaned, tempered and cooled, and heat treatment is completed after the tool is cooled.

In the quenching process, Daphne Hi-temp Oil A Oil is used, the Oil temperature of the quenching Oil is 137 ℃, workpieces are placed into the quenching Oil for 23min, and the Oil draining time is 33 min.

Heating at 274 deg.C for 163min during tempering, and cooling with air cooling after tempering.

The heat treatment method in the embodiment optimizes the atmosphere and medium control of the process, replaces and burns off the residual carbon in the atmosphere, controls and optimizes the flow of the enriched gas in the carburizing process, reduces the generation of newly added carbon black, and has good, uniform and consistent appearance of the whole furnace product without carbon black.

Referring to fig. 3 and 4, an embodiment of the present invention provides a heat treatment tool for the above heat treatment method, including a load-bearing shelf 1, where the load-bearing shelf 1 is substantially a square frame, and since the load-bearing shelf 1 needs to be placed in a heat treatment furnace, mounting holes 101 are provided at four corners of the load-bearing shelf 1, so that the load-bearing shelf 1 is fixed in the heat treatment furnace through the mounting holes 101, and since the load-bearing shelf 1 needs to be provided with an object to be heat-treated, the mounting holes 101 on the load-bearing shelf 1 need to have a certain length of hole diameter to maintain the structural strength of the load-bearing shelf 1, so that the mounting holes 101 occupy a space in the load-bearing shelf 1 where the object can be mounted, and the space utilization rate of.

In order to avoid the situation that the bearing shelf 1 is provided with the mounting holes 101 to reduce the space utilization rate, in the embodiment of the invention, the short clamping baffle 3 is horizontally and fixedly arranged at the top of the bearing shelf 1, the short clamping baffle 3 is also horizontally and fixedly arranged at the bottom of the bearing shelf 1, the short clamping baffle 3 at the top of the bearing shelf 1 corresponds to the short clamping baffle 3 at the bottom of the bearing shelf 1 in the vertical direction, two ends of the short clamping baffle 3 at the top are connected with the mounting holes 101 at the top of the bearing shelf 1, and two ends of the short clamping baffle 3 at the bottom are connected with the mounting holes 101 at the bottom of the bearing shelf 1.

The middle part of the bearing shelf 1 is horizontally and fixedly provided with a long clamping baffle 5, and the middle area of the bearing shelf 1 is not provided with a mounting hole 101, so that the length of the long clamping baffle 5 is greater than that of the short clamping baffle 3, the length of the long clamping baffle 5 is approximately the same as the side length of the bearing shelf 1, and the long clamping baffle 5 is parallel to the short clamping baffle 3.

In order to fix an object on the bearing shelf 1, a plurality of first bayonets 301 which are equidistantly spaced are arranged on the short bayonet baffle 3, a plurality of third bayonets 501 which are equidistantly spaced are arranged on the long bayonet baffle 5, the interval between the first bayonets 301 on the short bayonet baffle 3 is the same as the interval between the third bayonets 501 on the long bayonet baffle 5, the shape and the size of the first bayonets 301 are the same as those of the third bayonets 501, the length of the long bayonet baffle 5 is greater than that of the short bayonet baffle 3, and in the vertical direction, the plurality of first bayonets 301 of the short bayonet baffle 3 are in one-to-one correspondence with the plurality of third bayonets 501 in the middle of the long bayonet baffle 5, so that the first bayonets 301 on the short bayonet baffle 3 at the top, the third bayonets 501 on the long bayonet baffle 5 and the first bayonets 301 on the short bayonet baffle 3 at the bottom are located on the same vertical line.

Because the first bayonet socket 301 on the short bayonet socket baffle 3 at top, the third bayonet socket 501 of long bayonet socket baffle 5 and the first bayonet socket 301 on the short bayonet socket baffle 3 of bottom are located same vertical line, set up many long bars 2 on bearing shelf 1, the top of long bar 2 is located the first bayonet socket 301 of the short bayonet socket baffle 3 at bearing shelf 1 top, the bottom of long bar 2 is located the first bayonet socket 301 of the short bayonet socket baffle 3 of bearing shelf 1 bottom, the middle part of long bar 2 is located the third bayonet socket 501 of long bayonet socket baffle 5, the top and the bottom of long bar 2 that make are fixed by short bayonet socket baffle 3, the middle part is fixed by long bayonet socket baffle 5, the effectual condition that prevents long bar 2 from taking place to rock when thermal treatment and lead to thermal treatment poor effect appears.

Simultaneously, the third bayonet socket 501 on first bayonet socket 301 on the short bayonet socket baffle 3 and the long bayonet socket baffle 5 all is that the equidistance interval sets up, consequently, the interval between the long bar 2 that a plurality of be located first bayonet socket 301 and third bayonet socket 501 is also the equidistance, when guaranteeing to set up long bar 2 quantity on the bearing shelf 1, prevents to appear laminating between a plurality of long bar 2, leads to the inhomogeneous condition of carburization effect to appear.

In order to further improve the space utilization effect on the bearing shelf 1, the embodiment of the invention is characterized in that the bearing shelf 1 is provided with the additional clamping baffle 4, the additional clamping baffle 4 is arranged at the lower end of the mounting hole 101 at the top of the bearing shelf 1, the length of the additional clamping baffle 4 is larger than the diameter of the mounting hole 101, the short clamping baffle 3 and the additional clamping baffle 4 are overlapped in a certain length in the vertical direction, the additional clamping baffle 4 is provided with a plurality of second bayonets 401 at equal intervals, the interval between the second bayonets 401 is equal to the interval between the first bayonets 301, namely the interval between the second bayonets 401 is also equal to the interval between the third bayonets 501, meanwhile, the second bayonets 401 have the same shape and size as the first bayonets 301 and the third bayonets 501, the short bars 6 are arranged in the second bayonets 401 of the additional clamping baffle 4, so that the short bars 6 use the space at two sides of the bearing shelf 1, prevent that bearing shelf 1 from having the extravagant condition in space to, the top of section bar 6 is fixed by additional screens baffle 4, and the middle part is fixed by long screens baffle 5, prevents that short bar 6 from colliding with long bar 2 and leading to the poor condition of thermal treatment effect to appear.

In the embodiment of the invention, the upper end of the mounting hole 101 at the bottom of the bearing shelf 1 is provided with the additional clamping baffle 4, so that the top and the bottom of the short bar stock 6 are both fixed by the second bayonet 401 of the additional clamping baffle 4, and the stability of the short bar stock 6 in the heat treatment process is ensured.

In the embodiment of the invention, the products 7 are hung on the long bar materials 2 and the short bar materials 6, the products 7 are U-shaped teeth, and the long bar materials 2 and the short bar materials 6 are fixed by the first bayonet 301, the second bayonet 401 and the third bayonet 501 which are equidistantly spaced, so that the long bar materials 2 and the short bar materials 6 are equidistantly spaced, the products 7 hung on the long bar materials 2 and the short bar materials 6 are also equidistantly spaced, the plane joint of two adjacent rows of products 7 is prevented, the quality risk of uneven carburization effect caused by the plane joint of the products 7 is effectively avoided, and the quality risk of deformation and over-tolerance scrapping caused by mutual extrusion of the products 7 is effectively avoided.

In the embodiment of the invention, the short clamping baffle 3 and the additional clamping baffle 4 are combined for use, the space on the bearing shelf 1 is fully utilized, the long bar material 2 is arranged on the short clamping baffle 3, and the short bar material 6 is arranged on the additional clamping baffle 4, so that the number of the products 7 loaded on the bearing shelf 1 is greatly increased, the number of the products subjected to heat treatment at one time is increased, and the economic benefit of enterprises is increased.

The heat treatment tool is subjected to heat treatment according to the heat treatment method, 25056 workpieces can be subjected to heat treatment through one heat treatment, the charging quantity of the heat treatment tool is increased by 26.55% compared with that of a traditional heat treatment tool of 19800 workpieces, the number of the treatment furnaces is reduced to 400 from a planned 505 furnace according to the calculation of 1000 ten thousand workpieces per year capacity of a client, 105 furnace multiplied by 6 furnace multiplied by 630h is saved, the cost is saved by 9.5 ten thousand yuan per year according to the calculation of 150 yuan per hour, and the appearance quality defect that solid carbon black accumulates on the surface of the product 7 due to low temperature and high carbon potential and the internal quality defect that the seepage layer is not uniform and the hardened layer is not uniform due to the low temperature and high carbon potential can be effectively reduced for the product 7 after heat treatment, the risk that the product 7 fails early in the service process is eliminated, the fatigue resistance of the product can be improved, and the service.

The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present invention, and all the changes or substitutions should be covered within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the appended claims.