CN110468346A - A kind of hot die steel and manufacturing method of high intensity - Google Patents
A kind of hot die steel and manufacturing method of high intensity Download PDFInfo
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- CN110468346A CN110468346A CN201910805323.0A CN201910805323A CN110468346A CN 110468346 A CN110468346 A CN 110468346A CN 201910805323 A CN201910805323 A CN 201910805323A CN 110468346 A CN110468346 A CN 110468346A
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
- C21D1/18—Hardening; Quenching with or without subsequent tempering
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
- C21D1/26—Methods of annealing
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C33/00—Making ferrous alloys
- C22C33/04—Making ferrous alloys by melting
- C22C33/06—Making ferrous alloys by melting using master alloys
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/002—Ferrous alloys, e.g. steel alloys containing In, Mg, or other elements not provided for in one single group C22C38/001 - C22C38/60
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/02—Ferrous alloys, e.g. steel alloys containing silicon
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/04—Ferrous alloys, e.g. steel alloys containing manganese
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/22—Ferrous alloys, e.g. steel alloys containing chromium with molybdenum or tungsten
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/24—Ferrous alloys, e.g. steel alloys containing chromium with vanadium
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Materials Engineering (AREA)
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- Crystallography & Structural Chemistry (AREA)
- Heat Treatment Of Steel (AREA)
Abstract
The invention belongs to technical field of alloy steel, and in particular to a kind of high strength hot work die steel.The hot die steel is mainly made of the chemical component of following mass percentage: carbon 0.35-0.38%, silicon 0.2-0.3%, manganese 0.3-0.4%, chromium is 2.7-2.9%, molybdenum 2.5-2.6%, vanadium 0.9-1.1%, tungsten is 0.6-0.9%, and p and s content is respectively less than 0.03%, and surplus is iron.Formula is scientific and reasonable for hot die steel of the invention, and compared to 13 type hot die steel of conventional H, silicon and chromium content are reduced, and molybdenum content increases, and is added to wolfram element proof strength.Alloying component is tapped after ingredient, alloying are smelted, and is aided with 1040 DEG C of quenchings and 500-600 DEG C of tempering, so that the hot die steel being prepared has good comprehensive performance, intensity especially with higher is widely used.
Description
Technical field
The invention belongs to technical field of alloy steel, and in particular to a kind of high strength hot work die steel further relates to its manufacturer
Method.
Background technique
H13 steel is domestic and international mold materials most widely used hot die steel in the market, it is mainly for the manufacture of pressure
Mechanical press forging die, compression mod and hammer forging die, it is severe due to production status, it needs to bear during the military service of hot die steel biggish
Impact loading, but current H13 hot die steel does not have enough intensity to cope with increasingly complicated mold production
Environment.
Chinese patent CN101392353 discloses a kind of hot die steel that only addition wolfram element is strengthened, this is one
The quenched high heat-intensity hot-work die steel of kind, relies primarily in the martenaging martempering stage, the carbide of tungsten is precipitated to generate alloy carbon
Compound invigoration effect, and then reach material high intensity.However relying solely on wolfram element can make toughness of material decline, and cause material
The problem of service life shortens.
Chinese patent CN108070794 discloses a kind of side by adding ceramic composite powder and nano silicon carbide tungsten particle
Method improves the wearability of hot die steel.He mainly relies on ceramic composite powder, inorganic nano tungsten carbide, rare earth etc. compound
Reinforcing material improves abrasion resistance and hardness so that mould steel internal grain refines, structure is closely knit.However it is compound due to being related to
Material smelts manufacture, and process is complex, is not suitable for scale and smelts.
Compared to other countries, China is the big producer of H13 hot die steel, is not but production power.Domestic H13 steel
Often impurity is excessive, lower hardness, intensity are insufficient, and according to current problem, this patent proposes new H13 type hot die steel
Alloying component proportion and method of smelting, to guarantee the comprehensive performances such as its intensity with higher.
Summary of the invention
In view of the above, the invention discloses a kind of high strength hot work die steel and manufacturing methods, and formula is scientific and reasonable,
Compared to 13 type hot die steel of conventional H, silicon and chromium content are reduced, and molybdenum content increases, and is added to wolfram element proof strength.It closes
Golden ingredient is tapped after ingredient, alloying are smelted, and is aided with 1040 DEG C of quenchings and 500-600 DEG C of tempering, so that being prepared into
The novel H13 type hot die steel arrived has good comprehensive performance, and intensity especially with higher is widely used.
In order to solve the above-mentioned technical problem, the technical solution adopted by the present invention is that:
A kind of high intensity H13 type hot die steel, is made of the component of following mass percent: carbon 0.35-0.38%,
Silicon is 0.2-0.3%, manganese 0.3-0.4%, chromium 2.7-2.9%, molybdenum 2.5-2.6%, vanadium 0.9-1.1%, tungsten 0.6-
0.9%, p and s content is respectively less than 0.03%, and surplus is iron.
The preparation method of above-mentioned high strength hot work die steel, comprising the following steps:
(a) ingredient, smelting: each alloying component is weighed according to raw material proportioning, graphite and pure iron are heated to 1400-1500 DEG C
It is completely melt, is smelted into matrix molten iron；
(b) alloy compounds: ferrosilicon, manganese iron, chromium, molybdenum and tungsten being added into the matrix molten iron that step (a) obtains, is heated to
1600-1750 DEG C is completely melt, is smelted into molten steel；
(c) it refines: vanadium being added into the molten steel that step (b) obtains and stirs evenly, the molten steel after obtaining refinement crystal grain；
(d) it casts: in the steel ingot die that the resulting molten steel injection preheating of step (c) is completed, keeping the temperature 3 to 4 hours, so
After demould.
(e) it is heat-treated: the resulting steel ingot of step (d) being heat-treated, including annealing, quenching and tempering.
The heat treatment process of above-mentioned high strength hot work die steel, comprising the following steps:
(a) annealing temperature is 700 DEG C, and the time is 12 hours, is machined out after furnace cooling to room temperature.
(b) hardening heat is 1040 DEG C, is heated up with furnace, soaking time 24min, furnace oil is cold out.
(c) double tempering is carried out, tempering temperature is 500-600 DEG C, and soaking time 2h comes out of the stove and is air-cooled to room temperature.
The effect of microalloy element silicon, manganese, chromium, molybdenum, vanadium and tungsten in steel is different, and silicon can strengthen matrix and improve
Resistance to tempering；Manganese can mainly carry out solution strengthening, and eliminate the illeffects of sulphur；Chromium can be improved steel harden ability and anti-height
Warm oxidisability；Molybdenum then mainly improves alloy thermal stability and elevated temperature strength；Vanadium can refine crystal grain, improve Fracture of Material；Tungsten
The strength of materials, hardness and wearability can be improved.
Steel grade of the present invention mainly uses alloying means, improves the harden ability and intensity of mould steel, obtains lath martensite
Tissue topography, it is Mo, V, W-shaped at a large amount of high-melting-point MC type carbide and high intensity M2C-type carbide substantially increases the strong of material
Degree.
The Cr content of 4.75-5.5% makes after quenching when being tempered, and Cr and C form the carbide of high Cr, interferes have highly resistance
The VC of temper softening ability is formed, and heat resistance is reduced；When containing Cr, Mo, V in steel, the Cr greater than 3% content can prevent V4C3Life
At can also postpone Mo2The coherence of C is precipitated, and the two intersection interactions can promote elevated temperature strength and temper resistance.In addition, containing
The higher material of Cr will appear temper brittleness when quenching and carrying out 550-450 DEG C of tempering, therefore Cr content is controlled
In 2.7-2.9%.
1% or so Mo element and V element to generate post-curing in material drawing process, improves the anti-tempering of material
Softening power.Mo element obviously postpones perlitic transformation, generates post-curing with matrix coherence, the Mo of 0.25-1% can make pearl
Body of light transformation is distinguished with bainite transformation.The Mo of close-packed hexagonal structure is precipitated in martensite when tempering2C.Quality no more than 3%
Score is that Mo makes steel that the critical of decarburization sensitivity occur.Therefore Mo content is controlled in 2.5-2.6%.
But excessively high Mo can make Mo2C is changed into Mo6C, the bulky grain hand down austenite grain boundary and martensite lath circle
It is precipitated, causes alloy embrittlement.And W is dissolved type with Mo in steel and formation carbide is identical, atomic radius is approximate, considers
To Cr content to the reduction of heat resistance and the embrittling effect of excessively high Mo, it is strong that W element increase material similar with Mo can be added
Spend hardness and wearability.In view of cost factor, W content is controlled in 0.6-0.9%.
Beneficial outcomes of the invention: novel H13 type hot die steel of the invention is aided with multiple element composite alloying
Vacuum melting and appropriate heat treatment process, comprehensively considered chemical component, preparation method and heat treatment mode to its performance and
The influence of service life, even tissue, steel are pure, Rockwell hardness with higher and tensile strength, are a kind of high-intensitive new
Type hot die steel.
Detailed description of the invention
Fig. 1 is 1 annealed structure figure of the embodiment of the present invention.
Fig. 2 is the embodiment of the present invention 2 in 550 degree of tempered structure figures.
Fig. 3 is the tempering temperature hardness balance figure different from 13 steel of conventional H of the embodiment of the present invention 1.
Fig. 4 is the tempering temperature tensile strength comparison diagram different from 13 steel of conventional H of the embodiment of the present invention 1.
Fig. 5 is shown after the embodiment of the present invention 1 stablizes experiment from progress 22h tempering under the different tempering temperatures of 13 steel of conventional H
Microhardness comparison diagram.
Specific embodiment
The principle of the present invention feature is continued to describe below in conjunction with example, example is served only for explaining invention, not uses
In limiting the scope of the invention.
Embodiment 1:
A kind of hot die steel mass fraction is as follows: carbon 0.37%, silicon 0.2%, manganese 0.35%, chromium 2.9%,
Molybdenum 2.5%, vanadium 1.1%, tungsten 0.9%, p and s content are respectively less than 0.03%, and surplus is iron.
The preparation of above-mentioned hot die steel the following steps are included:
(a) ingredient, smelting: weighing each alloying component according to raw material proportioning, and graphite and pure iron are heated to 1500 DEG C completely
Fusing, is smelted into matrix molten iron；
(b) alloy compounds: ferrosilicon, manganese iron, chromium, molybdenum and tungsten being added into the matrix molten iron that step (a) obtains, is heated to
1750 DEG C are completely melt, are smelted into molten steel；
(c) it refines: vanadium being added into the molten steel that step (b) obtains and stirs evenly, the molten steel after obtaining refinement crystal grain；
(d) it casts: in the steel ingot die that the resulting molten steel injection preheating of step (c) is completed, keeping the temperature 4 hours, then
Demoulding.
(e) it is heat-treated: the resulting steel ingot of step (d) being heat-treated, including annealing, quenching and tempering.
The above-mentioned steel for preparing is annealed, annealing temperature is 700 DEG C, and the time is 12 hours, furnace cooling to room temperature.Then
Quenching and tempering process are carried out, hardening heat is 1040 DEG C, is heated up with furnace, soaking time 24min, furnace oil is cold out.It carries out again
Double tempering, the tempering temperature for carrying out double tempering and double tempering to workpiece is identical, respectively 500 DEG C, 550 DEG C, 600 DEG C,
Soaking time is 2 hours, comes out of the stove and is air-cooled to room temperature.
Embodiment 2:
A kind of hot die steel mass fraction is as follows: carbon 0.35%, silicon 0.3%, manganese 0.4%, chromium 2.7%,
Molybdenum 2.55%, vanadium 1.1%, tungsten 0.6%, p and s content are respectively less than 0.03%, and surplus is iron.
The preparation of above-mentioned hot die steel the following steps are included:
(a) ingredient, smelting: weighing each alloying component according to raw material proportioning, and graphite and pure iron are heated to 1500 DEG C completely
Fusing, is smelted into matrix molten iron；
(b) alloy compounds: ferrosilicon, manganese iron, chromium, molybdenum and tungsten being added into the matrix molten iron that step (a) obtains, is heated to
1750 DEG C are completely melt, are smelted into molten steel；
(c) it refines: vanadium being added into the molten steel that step (b) obtains and stirs evenly, the molten steel after obtaining refinement crystal grain；
(d) it casts: in the steel ingot die that the resulting molten steel injection preheating of step (c) is completed, keeping the temperature 3 hours, then
Demoulding.
(e) it is heat-treated: the resulting steel ingot of step (d) being heat-treated, including annealing, quenching and tempering.
The above-mentioned steel for preparing is annealed, annealing temperature is 700 DEG C, and the time is 12 hours, furnace cooling to room temperature.Quenching
Temperature is 1040 DEG C, is heated up with furnace, soaking time 24min, furnace oil is cold out.Double tempering and double tempering are carried out to workpiece
Tempering temperature is identical, and respectively 500 DEG C, 550 DEG C, 600 DEG C, soaking time 2h come out of the stove and is air-cooled to room temperature.
In order to verify hot-work die Steel Properties provided by the invention, the resulting hot die steel of embodiment 1 (is denoted as
CXN215 steel) annealed structure and the resulting hot die steel of embodiment 2 (being denoted as CXN218 steel) 550 degree of tempered structures carry out
Observation, acquired results are as shown in Figure 1 and Figure 2.As shown in Figure 1, CXN215 steel annealed structure is uniform, finds no oversized, shape
The presence of the eutectic carbide of shape complexity, is organized as ferrite and granular carbide.As shown in Figure 2, CXN218 steel tempering horse
Family name's body, retained austenite and micro granular carbide.
It is hard after having carried out tempering hardness, tensile strength to CXN215 steel and 13 hot die steel of conventional H, be tempered stable experiment
The comparative experiments of degree, acquired results are as shown in figure 3, figure 4 and figure 5.From the figure 3, it may be seen that two kinds when tempering temperature is 500 DEG C and 550 DEG C
Material hardness is not much different, and when tempering temperature is 600 DEG C, the hardness of decline and CXN215 steel by a relatively large margin occurs for H13 steel hardness
Higher than H13 steel.As shown in Figure 4, two kinds of Tensile strengths are not much different when tempering temperature is 500 DEG C and 550 DEG C tempering, are tempered
There is different degrees of decline in two Tensile strengths when temperature is 600 DEG C of tempering, and wherein the H13 steel range of decrease is bigger.It can by Fig. 5
Know, for CXN215 steel after different tempering temperatures carry out 22 hours tempering steady testings, microhardness is above 13 steel of conventional H.
By above-mentioned data and result it is found that the hot die steel that the present invention is prepared has good comprehensive performance, especially
It is intensity with higher, is widely used, and the application field of existing mold steel has been widened.
For those skilled in the art, under the premise of not departing from the present invention program, several changes can also be made
Shape and improvement, these also should be considered as protection scope of the present invention, these all will not influence the effect and patent that the present invention is implemented
Practicability.
Claims (5)
1. a kind of high strength hot work die steel, which is characterized in that be made of the component of following mass percent: carbon 0.35-
0.38%, silicon 0.2-0.3%, manganese 0.3-0.4%, chromium 2.7-2.9%, molybdenum 2.5-2.6%, vanadium 0.9-1.1%, tungsten
For 0.6-0.9%, p and s content is respectively less than 0.03%, and surplus is iron.
2. a kind of preparation method of high strength hot work die steel as described in claim 1, which is characterized in that specific steps are such as
Under:
(a) ingredient, smelting: weighing each alloying component according to raw material proportioning, and graphite and pure iron are heated to 1400-1500 DEG C completely
Fusing, is smelted into matrix molten iron；
(b) alloy compounds: ferrosilicon, manganese iron, chromium, molybdenum and tungsten being added into the matrix molten iron that step (a) obtains, is heated to 1600-
1750 DEG C are completely melt, are smelted into molten steel；
(c) it refines: vanadium being added into the molten steel that step (b) obtains and stirs evenly, the molten steel after obtaining refinement crystal grain；
(d) it casts: in the steel ingot die that the resulting molten steel injection preheating of step (c) is completed, keeping the temperature 3 to 4 hours, then take off
Mould；
(e) it is heat-treated: the resulting steel ingot of step (d) being heat-treated, including annealing, quenching and tempering.
3. a kind of preparation method of high strength hot work die steel as claimed in claim 2, which is characterized in that annealing temperature is
700 DEG C, the time is 12 hours, is machined out after furnace cooling to room temperature.
4. a kind of preparation method of high strength hot work die steel as claimed in claim 2, which is characterized in that hardening heat is
It 1040 DEG C, heats up with furnace, soaking time 24min, furnace oil is cold out.
5. a kind of preparation method of high strength hot work die steel as claimed in claim 2, which is characterized in that returned twice
Fire, tempering temperature are 500-600 DEG C, and soaking time 2h comes out of the stove and is air-cooled to room temperature.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113333738A (en) * | 2021-06-23 | 2021-09-03 | 广东省科学院中乌焊接研究所 | Novel H13 steel powder for additive manufacturing and preparation method thereof |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109487166A (en) * | 2018-12-21 | 2019-03-19 | 北京科技大学 | A kind of high strength at high temperature low-carbon heated die steel and preparation method thereof |
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- 2019-08-29 CN CN201910805323.0A patent/CN110468346A/en active Pending
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109487166A (en) * | 2018-12-21 | 2019-03-19 | 北京科技大学 | A kind of high strength at high temperature low-carbon heated die steel and preparation method thereof |
Non-Patent Citations (2)
| Title |
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| 孙斌煜等: "《钢铁生产概论》", 30 September 2017, 冶金工业出版社 * |
| 易文质: "《模具热处理》", 30 April 1981, 湖南科学技术出版社 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113333738A (en) * | 2021-06-23 | 2021-09-03 | 广东省科学院中乌焊接研究所 | Novel H13 steel powder for additive manufacturing and preparation method thereof |
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