阅读说明：本技术 一种防变形的高寿命、高强度的模具钢及制作方法 (Anti-deformation die steel with long service life and high strength and manufacturing method thereof ) 是由 徐卫明 顾金才 于广文 周青春 罗晓芳 于 2020-05-09 设计创作，主要内容包括：本发明公开了一种防变形的高寿命、高强度的模具钢及制作方法,具体涉及模具钢领域,其中所使用的主料包括以下重量份数的元素：碳C：0.3-0.5份、锰Mn：21.0-24.0份、铬Cr：3-5份、钼Mo：1.8-2.2份、硅Si：≤0.80份、磷P：≤0.10份、硫S：≤0.030份,余量为铁和不可避免的杂质,所述辅料原料设置为氮气。本发明通过各原料组分间的配合及制备方法的施用,可提高合金的原子间结合力,提高强度制得强度更高的模具钢,高温模具钢外壁与氮气接触进行渗氮处理,可提高模具钢的表面硬度,通过不同温度下的回火、淬火工艺步骤,不仅可提高模具钢的强度,而且可保证模具钢的韧性,从而进一步的保证模具钢的使用寿命。(The invention discloses anti-deformation long-life high-strength die steel and a manufacturing method thereof, and particularly relates to the field of die steel, wherein the used main materials comprise the following elements in parts by weight: c, carbon C: 0.3-0.5 parts of manganese Mn: 21.0-24.0 parts of chromium Cr: 3-5 parts of molybdenum Mo: 1.8-2.2 parts of silicon Si: less than or equal to 0.80 parts, phosphorus P: less than or equal to 0.10 part, sulfur S: less than or equal to 0.030 parts, the balance of iron and inevitable impurities, and the auxiliary material raw material is nitrogen. According to the invention, through the matching among the raw material components and the application of the preparation method, the interatomic bonding force of the alloy can be improved, the strength is improved, and the die steel with higher strength is prepared, the outer wall of the high-temperature die steel is in contact with nitrogen for nitriding treatment, so that the surface hardness of the die steel can be improved, and through the tempering and quenching process steps at different temperatures, not only can the strength of the die steel be improved, but also the toughness of the die steel can be ensured, so that the service life of the die steel is further ensured.)

1. The utility model provides a mould steel of high life, high strength of preapring for an unfavorable turn of events shape which characterized in that: the used main materials comprise the following elements in parts by weight: c, carbon C: 0.3-0.5 parts of manganese Mn: 21.0-24.0 parts of chromium Cr: 3-5 parts of molybdenum Mo: 1.8-2.2 parts of silicon Si: less than or equal to 0.80 parts, phosphorus P: less than or equal to 0.10 part, sulfur S: less than or equal to 0.030 parts, the balance of iron and inevitable impurities, and the auxiliary material raw material is nitrogen.

2. The deformation-resistant long-life high-strength die steel as claimed in claim 1, wherein: the used main materials comprise the following elements in parts by weight: c, carbon C: 0.5 part, Mn: 24.0 parts of chromium Cr: 5 parts of molybdenum Mo: 2.2 parts, silicon Si: 0.76 part, phosphorus P: 0.08 parts of sulfur S: 0.027 parts of iron and inevitable impurities as the balance, and the auxiliary material is nitrogen.

3. The deformation-resistant long-life high-strength die steel as claimed in claim 1, wherein: the used main materials comprise the following elements in parts by weight: c, carbon C: 0.3 part, Mn: 21.0 part of chromium Cr: 3 parts of molybdenum Mo: 1.8 parts, silicon Si: 0.76 part, phosphorus P: 0.08 parts of sulfur S: 0.027 parts of iron and inevitable impurities as the balance, and the auxiliary material is nitrogen.

4. The deformation-resistant long-life high-strength die steel as claimed in claim 1, wherein: the used main materials comprise the following elements in parts by weight: c, carbon C: 0.3 part, Mn: 21.0 part of chromium Cr: 3 parts of molybdenum Mo: 1.8 parts, silicon Si: 0.76 part, phosphorus P: 0.08 parts of sulfur S: 0.027 parts, and the balance of iron and inevitable impurities.

5. The deformation-resistant long-life high-strength die steel as set forth in any one of claims 1 to 4, wherein: the method also comprises a manufacturing method of the anti-deformation die steel with long service life and high strength, and the specific preparation steps are as follows:

s1, refining molten steel: preheating a smelting furnace, adding a pig iron raw material or a waste iron raw material into the smelting furnace, raising the temperature to 900-1100 ℃, adding corresponding component raw materials in proportion by adopting a non-oxidation method, mixing, heating and melting;

s2: heating the molten steel prepared in the step S1 to 1400-1500 ℃, performing deoxidation treatment, performing inoculation modification treatment on the molten steel by a flushing method, and then performing decarburization treatment by an oxygen blowing method;

s3, casting a mould blank:

s3.1: cooling the molten steel prepared in the step S2 to 1100-1150 ℃, and pouring into a die steel blank sample;

s3.2: annealing the blank sample formed in the step S3.1 at 750-800 ℃, and machining the blank sample into a standard sample;

s4, quenching the standard sample prepared in the step S3.2 by using engine oil after the temperature is raised to 960-980 ℃;

s5, tempering the die steel blank sample quenched in the step S4;

and S6, taking out the tempered die steel piece, cooling in a nitrogen environment, and turning to the room to naturally cool to room temperature after the surface temperature of the die steel is reduced to 100-150 ℃ to obtain the die steel piece.

6. The method for manufacturing the deformation-preventing long-life high-strength die steel according to claim 5, wherein the method comprises the following steps: the inoculation and modification time in the step S2 is set to be 6-12 min.

7. The method for manufacturing the deformation-preventing long-life high-strength die steel according to claim 5, wherein the method comprises the following steps: and in the step S4, the quenching heat preservation time is set to be 40 min.

8. The method for manufacturing the deformation-preventing long-life high-strength die steel according to claim 5, wherein the method comprises the following steps: in the step S5, the tempering temperature is 500 ℃, the tempering medium is air, and the tempering heat preservation time is 2 hours.

Technical Field

The invention relates to the technical field of die steel, in particular to anti-deformation die steel with long service life and high strength and a manufacturing method thereof.

Background

Die steel is a steel grade used for manufacturing dies such as cold stamping dies, hot forging dies, die casting dies and the like. The die is a main processing tool for manufacturing parts in industrial departments of mechanical manufacturing, radio instruments, motors, electric appliances and the like. The quality of the die directly affects the quality of the pressure processing technology, the precision yield of products and the production cost, and the quality and the service life of the die are mainly affected by die materials and heat treatment except by reasonable structural design and processing precision. The die steel can be roughly divided into cold-rolled die steel, hot-rolled die steel and plastic die steel, and is used for forging, stamping, cutting, die-casting and the like. Because of the complicated working conditions and different applications of various dies, the die steel should have high hardness, strength, wear resistance, sufficient toughness, and high hardenability, and other processing properties according to the working conditions of the die manufactured from the die steel. Since such applications are different and the working conditions are complicated, the performance requirements for the steel for molds are also different. The cold rolling die comprises a cold stamping die, a wire drawing die, a drawing die, an embossing die, a thread rolling plate, a cold heading die, a cold extrusion die and the like. The steel for cold-working dies should have high hardness, strength, wear resistance, sufficient toughness, and high hardenability, and other processing properties according to the working conditions under which it is manufactured. The steel for alloy tools used for such applications is generally a high carbon alloy steel with a carbon content of 0.80% or more, and chromium is an important alloying element of such steel, and its mass fraction is usually not more than 5%. However, for some die steels with high requirements on wear resistance and small deformation after quenching, the mass fraction of the highest chromium can reach 13%, and the mass fraction of the carbon in the steel is also high to form a large amount of carbides, and can reach 2.0% -2.3%. The cold-work die steel has high carbon content, and most of the structure of the cold-work die steel belongs to hypereutectoid steel or ledeburite steel. Common steels include high carbon low alloy steel, high carbon high chromium steel, chrome molybdenum steel, medium carbon chrome wolfram steel, etc. The hot rolling die is divided into several main types, including hammer forging, die forging, extrusion and die casting, including hot forging die, press forging die, stamping die, hot extrusion die, metal die casting die, etc. In addition to the great mechanical stress, the hot deformation mold is subjected to repeated heating and cooling during operation, which causes great thermal stress. The hot work die steel should have high hardness, strength, red hardness, wear resistance and toughness, good high temperature strength, thermal fatigue stability, thermal conductivity and corrosion resistance, and high hardenability to ensure the uniform mechanical properties of the whole section. For steel for die casting molds, it should also have the property that the surface layer does not crack upon repeated heating and cooling, and withstands the impact and erosion of liquid metal flow. The steel belongs to medium carbon alloy steel, the carbon content is 0.30-0.60%, the steel belongs to hypoeutectoid steel, and part of the steel is eutectoid or hypereutectoid steel due to the addition of more alloying elements (such as tungsten, molybdenum, vanadium and the like). The steel used in common use includes chrome manganese steel, chrome nickel steel, chrome tungsten steel, etc. Plastic molds include thermoplastic molds and thermoset molds. The steel for plastic molds is required to have certain properties such as strength, hardness, wear resistance, thermal stability, corrosion resistance and the like. In addition, good manufacturability such as small heat treatment deformation, good processability, good corrosion resistance, good grinding and polishing properties, good repair welding properties, high roughness, good thermal conductivity, stable size and shape of working conditions, and the like is also required. In general, hot-work die steel can be selected as the injection molding or extrusion molding die; the mould which is formed by thermosetting and requires high wear resistance and high strength can be selected from cold-work mould steel.

The existing die steel has poor hardness in the using process, and no matter the existing die steel is pouring die steel or impact die steel in the manufacturing process of the die, the shape of the existing die steel can be correspondingly changed under the action of high temperature or high pressure after the existing die steel is used for many times, so that the hot work die steel is required to have good strength, and otherwise, the normal use of the existing die steel can be influenced.

Disclosure of Invention

In order to overcome the above defects in the prior art, embodiments of the present invention provide a deformation-resistant, long-life, high-strength die steel and a manufacturing method thereof, and the technical problems to be solved by the present invention are: how to improve the strength of the existing die steel, thereby ensuring the service life of the die steel.

In order to achieve the purpose, the invention provides the following technical scheme: the anti-deformation long-life high-strength die steel comprises the following main materials in parts by weight: c, carbon C: 0.3-0.5 parts of manganese Mn: 21.0-24.0 parts of chromium Cr: 3-5 parts of molybdenum Mo: 1.8-2.2 parts of silicon Si: less than or equal to 0.80 parts, phosphorus P: less than or equal to 0.10 part, sulfur S: less than or equal to 0.030 parts, the balance of iron and inevitable impurities, and the auxiliary material raw material is nitrogen.

In a preferred embodiment, the main material used comprises the following elements in parts by weight: c, carbon C: 0.5 part, Mn: 24.0 parts of chromium Cr: 5 parts of molybdenum Mo: 2.2 parts, silicon Si: 0.76 part, phosphorus P: 0.08 parts of sulfur S: 0.027 parts of iron and inevitable impurities as the balance, and the auxiliary material is nitrogen.

In a preferred embodiment, the main material used comprises the following elements in parts by weight: c, carbon C: 0.3 part, Mn: 21.0 part of chromium Cr: 3 parts of molybdenum Mo: 1.8 parts, silicon Si: 0.76 part, phosphorus P: 0.08 parts of sulfur S: 0.027 parts of iron and inevitable impurities as the balance, and the auxiliary material is nitrogen.

In a preferred embodiment, the main material used comprises the following elements in parts by weight: c, carbon C: 0.3 part, Mn: 21.0 part of chromium Cr: 3 parts of molybdenum Mo: 1.8 parts, silicon Si: 0.76 part, phosphorus P: 0.08 parts of sulfur S: 0.027 parts, and the balance of iron and inevitable impurities.

The invention also discloses a manufacturing method of the anti-deformation die steel with long service life and high strength, which comprises the following specific preparation steps:

s1, refining molten steel: preheating a smelting furnace, adding a pig iron raw material or a waste iron raw material into the smelting furnace, raising the temperature to 900-1100 ℃, adding corresponding component raw materials in proportion by adopting a non-oxidation method, mixing, heating and melting;

s2: heating the molten steel prepared in the step S1 to 1400-1500 ℃, performing deoxidation treatment, performing inoculation modification treatment on the molten steel by a flushing method, and then performing decarburization treatment by an oxygen blowing method;

s3, casting a mould blank:

s3.1: cooling the molten steel prepared in the step S2 to 1100-1150 ℃, and pouring into a die steel blank sample;

s3.2: annealing the blank sample formed in the step S3.1 at 750-800 ℃, and machining the blank sample into a standard sample;

s4, quenching the standard sample prepared in the step S3.2 by using engine oil after the temperature is raised to 960-980 ℃;

s5, tempering the die steel blank sample quenched in the step S4;

and S6, taking out the tempered die steel piece, cooling in a nitrogen environment, and turning to the room to naturally cool to room temperature after the surface temperature of the die steel is reduced to 100-150 ℃ to obtain the die steel piece.

In a preferred embodiment, the inoculation and modification treatment time period in the step S2 is set to 6-12 min.

In a preferred embodiment, the quenching heat-preserving time in the step S4 is set to 40 min.

In a preferred embodiment, the tempering temperature in step S5 is 500 ℃, the tempering medium is air, and the tempering holding time is 2 h.

The invention has the technical effects and advantages that:

according to the invention, through the matching among the raw material components and the application of the preparation method, the interatomic bonding force of the alloy can be improved, the strength is improved, and the die steel with higher strength is prepared, the heat-resisting melting loss resistance of the die steel can be improved by adding the cr element, and meanwhile, the compact oxide film is promoted to be formed in the friction process and is tightly bonded with the matrix, and the outer wall of the high-temperature die steel is in contact with nitrogen for nitriding treatment, so that the surface hardness of the die steel can be improved, and through the tempering and quenching process steps at different temperatures, the strength of the die steel can be improved, and the toughness of the die steel can be ensured, so that the service life of the die steel is further ensured.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.