CN103334052A - High-thermal conductivity high-abrasion resistance hot stamping die steel and preparation method thereof - Google Patents
High-thermal conductivity high-abrasion resistance hot stamping die steel and preparation method thereof Download PDFInfo
- Publication number
- CN103334052A CN103334052A CN2013102413729A CN201310241372A CN103334052A CN 103334052 A CN103334052 A CN 103334052A CN 2013102413729 A CN2013102413729 A CN 2013102413729A CN 201310241372 A CN201310241372 A CN 201310241372A CN 103334052 A CN103334052 A CN 103334052A
- Authority
- CN
- China
- Prior art keywords
- steel
- hot stamping
- stamping die
- content
- annealing
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Landscapes
- Heat Treatment Of Articles (AREA)
Abstract
The invention relates to a novel high-thermal conductivity high-abrasion resistance hot stamping die material. The current hot stamping die steels on the market are mainly various improved high alloy steels such as H13 steel, H11 steel and the like. The steel disclosed by the invention comprises the following components in percentage by mass: 0.45-0.5% of C, less than 0.2% of Si, less than 0.20% of Mn, 1.0-2.0% of W, 2.0-3.5% of Mo, less than 0.30% of Cr and the balance of Fe and other unavoidable impurity elements, wherein the S content is less than or equal to 0.03% and the P content is less than or equal to 0.03% in the impurity elements. The steel has the characteristics that simple C, Mo and W elements are taken as the main components and the proportion of carbide is coordinated; low Mn content, low Cr content and super low Si content are kept; the material has good machinability after being subjected to electric-furnace smelting, electroslag remelting, annealing, high-temperature homogenizing, forging and annealing; after being subjected to heat treatment (quenching at the temperature of 1060-1100 DEG C and repeatedly high-temperature tempering), the steel has the toughness of general hot stamping die steels such as H13 steel and is better in hardness, tempering stability and thermal fatigue property; and the steel is more suitable for hot stamping due to the advantages of lower thermal expansion coefficient, high thermal conduction ability and high abrasion resistance particularly.
Description
Technical field
The present invention relates to a kind of high thermal conductivity high abrasion hot stamping die steel and preparation method thereof.
Background technology
Along with the high speed development of automobile industry, and the proposition of automobile lightweight demand, superstrength stamping parts demand promotes day by day.It is big that cold punching forming process obtains the required pressure of ultrahigh-strength steel, reduces die life easily, and also easily produce break, wrinkling, problem such as dimensional precision is bad.And hot press-formed technology utilization metal is under the condition of high temperature, and plasticity and ductility increase, and yield strength descends, and therefore is used widely.
The steel hot stamping process is that special high tensile steel plate is heated to the austenitic temperature scope, move quickly into mould, punching press is fast carried out quench cooled by the mould that is furnished with cooling loop to part under the press packing state, obtain the superstrength stamping parts at last.When work, because mould directly contacts with the blank of heating, when red-hot metal was put into the hot stamping die die cavity, mold cavity surface sharply heated up, and the top layer produces stress and compressive strain when punching press and pressurize, and this makes mould need heat resistance and thermostability preferably; Also will bear strong plastic friction and wearing and tearing, mould also needs higher wear resistance; In pressure maintaining period, by the mould that has cooling water channel component are quenched, in order to make mould can be soon take away and guarantee the mould precision in the process under arms to the heat of steel plate, moulding stock must have bigger thermal conductivity and less thermal expansivity; When metalwork took out, mold cavity surface was subjected to tensile stress and stretching strain effect owing to rapid cooling, very easily produced thermal fatigue at the operating mode bed die of this checker temperature; And the hot stamping die steel in the process, also will be subjected to greater impact load, so mould need possess good toughness under arms.Be the plucking that prevents that die surface from producing in the process under arms, mould also need have higher hardness.Therefore, Fu Za working condition requirement hot stamping die material has high thermal, wear resistance, hot strength, hardness, impelling strength, hardening capacity and thermostability and cold-and-heat resistent fatigue property etc.
What at present, the hot stamping die steel that uses of China adopted is that grade of steel is equivalent to North America standard H13 steel as 4Cr5MoSiV1(among standard GB/T1299-2000).The chemical ingredients of this hot stamping die steel adopts C 0.32-0.45wt%, Cr 4.75-5.50wt%, Mo 1.20-1.75 wt%, V 0.80-1.20 wt%, Si 0.80-1.2wt%, Mn 0.20-0.5wt%, P≤0.03wt%, S≤0.03wt%.At present, what Japanese enterprises adopted is that hot-work die steel SKD61(is equivalent to North America standard H13 steel), that Sweden hot stamping die supplier adopts is ORVAR, what German enterprise adopted is CR7V and 1.2379.Theoretically, ferritic thermal conductivity is the highest in the tissue of steel, is about 71 ~ 80W/mK, and the tempered martensite thermal conductivity is 35W/mK, and the thermal conductivity of cementite is minimum to be 7W/mK.Carbon Medium Alloy Steel during existing H13 hot stamping die steel belongs to, ferritic ratio is not high in the tempered martensite that obtains.From thermal conduction mechanism, for pure metal, moving heat conduction by unbound electron is main mechanism.For unbound electron heat conduction, heat conducting resistance mainly be the lattice vibration phonon to the scattering process of unbound electron, temperature increases, the lattice vibration aggravation, phonon increases the resistance of unbound electron motion, causes its capacity of heat transmission to descend.Existing H13 steel contains the alloying element of more kind, and the existence of alloying element causes the lattice distortion of atom iron, reduces thermal conductivity; Particularly contain higher Si element in the Chemical Composition, the outer electronic structure of Si and Fe differ greatly, can the serious thermal conductivity that reduces steel.The wear resistance of H13 steel is main, and to contain the content of Mo, V and C relevant with steel, but the H13 steel is 45-49HRC through hardness behind the Q-tempering, and when 500 ℃ of left and right sides of working temperature, the wear resistance of mould is not enough, and lack work-ing life, and the surface quality of shaped material is relatively poor.
China and foreign countries' patent retrieval content analysis to correlation technique
By the keyword of importing relevant content of the present invention China and foreign countries' patent is being retrieved discovery, relating to the hot-work die steel that is associated with this patent and the patent No. of metallurgical manufacturing technology thereof and be
(1) number of patent application: 201110007324.4, title: the wear-resisting hot stamping die alloy steel material of heat resistance, its chemical component weight degree is: C=0.40 ~ 0.50, Si=0.3 ~ 0.5; Mn=0.65 ~ 0.85; P＜0.025; S＜0.005; Cr2.5 ~ 2.7; Mo=2.1 ~ 2.4; V=0.8 ~ 1.0; All the other are Fe and trace impurity.
(2) number of patent application: 200810046104.0, title: a kind of novel chromium system hot die steel and thermal treatment process thereof, its Chemical Composition weight percent content is: carbon C 0.35～0.7%, silicon Si 0.3～1.3%, manganese Mn 0.3～1.3%, chromium Cr 7.0～11.0%, tungsten W 0.4～1.2%, molybdenum Mo 0.4～1.2%, vanadium V 0.4～1.2%, nickel 1.0%, sulphur S≤0.005%, phosphorus P≤0.030%, boron 0.03%-0.10%, the scope of amount of nitrides is 0.02%≤nitride≤0.20%, 0.02%≤nitrogen N≤0.10%, and its surplus is iron Fe.
(3) number of patent application: 201080014370.0, title: have the hot working tool steel of outstanding toughness and thermal conductivity, its Chemical Composition weight percent content is: C=0.2-1.2%; N=0-1%; B=0-1%; Cr＜1.5%; Ni=1.0-9; Si＜0.4; Mn=0-3%; Al=0-2.5%; Mo=0-10%; W=0-15%; Ti=0-3%; Ta=0-3%; Zr=0-3%; Hf=0-3%; V=0-4%; Nb=0-3%; Cu=0-4%; Co=0-6%; S=0-1%; Se=0-1%; Te=0-1%; Bi=0-1%; As=0-1%; Sb=0-1%; Ca=0-1%; Surplus is made of iron and unavoidable impurities, and wherein %Ceq=%C+0.86*%N+1.2*%B is characterized in that %Mo+1/2*%W〉1.2.
(4) number of patent application: 200710170723.6, title: a kind of hot-work die steel with good heat resistance and high tenacity, its chemical component weight degree is: C 0.28～0.35, Si 0.20～0.50, Mn 0.20～0.80, Cr 4.50～5.50, Mo 2.00～2.80, V 0.4～0.80, P≤0.025, S≤0.025, Nb 0.05～0.20, N 0.01～0.03, surplus are Fe and inevitable impurity element.
Comparative analysis is as follows: from the contrast of composition as can be seen, the constituent content of Chemical Composition of the present invention is obviously different with patent 1-4, and element is also just different to the mechanism of the performance effect of material, and the applied environment of material is also different.
(1) patent application 201110007324.4 and this patent similarity are, in order to obtain heat-resistant antifriction hot stamping die steel, adopt lower Si and the content of Mn, control low levels Cr element, and increased W and Mo, two patent alloying principles have added V; Add V energy crystal grain thinning, the VC of formation improves wear resistance.The present invention want with it than under lower Si, Mn, the Cr of control, mainly be to obtain more ferrite matrix by low alloying, thereby obtain more thermal conductivity, increase Mo content, also can improve wear resistance.The effect of adding W is to make steel obtain better hot strength and temper resistance etc.
(2) patent 200810046104.0 brings up to 7 ~ 11% with chromium content, can improve tempering temperature and erosion resistance.But when containing chromium, molybdenum in the steel, Cr〉3% o'clock, chromium can be postponed the coherence of Mo2C and be separated out, and Mo2C improves the hot strength of steel and the strengthening phase of temper resistance.And the interpolation of alloying elements cr can reduce the thermal conductivity of steel.And the present invention and its Chemical Composition are by contrast controlled Cr content below 0.3% in forming, and do not use the Cr element substantially, and the hot stamping die steel that makes the present invention make has better thermal conductivity, hot strength and temper resistance.What patent 200810046104.0 was different with the present invention is to have added 1% nickel, and this compares the characteristics that have with the present invention be by having increased nickel in steel, having come crystal grain thinning to increase toughness.And adding Ni, the present invention can not obtain thinner tissue yet, patent 200810046104.0 Chemical Composition composition is compared unique similar part with the present invention be Mo, V and the W element that adds, but the present invention adds Mo and W is higher than patent 200810046104.0, this makes and forms a large amount of tungsten in the tissue of material and the carbide of molybdenum carries out build up, the content of V is very approaching, mainly increases wear resistance in order to form VC.The present invention and its Chemical Composition does not by contrast add nickel element in forming, control lower silicon, manganese, chromium constituent content, and minimizing carbon content, increase Mo and W content, its strengthening effect to performance mainly is by low alloying (the low manganese chromium of low silicon), low-carbon (LC) obtains more ferrite matrixes, thereby obtains higher thermal conductivity, and the compound action of the multiple carbide of molybdenum and tungsten obtains the better hot strength of steel and temper resistance etc.
(3) the similar part of patent 201080014370.0 and the present invention is to be in order to obtain the high heat conductance tool steel.The present invention adopts control low C, Si, Mn, Cr element, add W, V and Mo, but patent 201080014370.0 has been added Ni, Nb, N and B; Ni is conducive to improve hardening capacity, Nb energy crystal grain thinning, and being added with of B and N is beneficial to the acquisition high heat conductance.In order to coordinate the ratio that Mo, V and W form carbide, C content is controlled 0.45 ~ 0.5, thereby obtains more high heat conductance.The effect that adds Mo and V is to improve wear resistance, and increasing W is in order to play strengthening effect, to play the effect that improves temper resistance and thermal fatigue ability.
(4) the similar part of patent 200710170723.6 and the present invention is that the Mo content that adds is much the same, mainly is that Mo2C separated out in martensite during for tempering, makes steel have age hardening effect.But the Si of patent 200710170723.6, Mn, Cr content is all than the present invention height, and increased Nb and N, and adding V is for crystal grain thinning, the anti-temper softening ability of the carbide strongthener that Nb obtains.The content that the present invention increases V mainly is in order to obtain carbide to improve wear resistance, crystal grain thinning; Adding W mainly is in order to improve thermostability.Having increased C is in order to coordinate the formation of carbide, to improve wear resistance and the high-temperature stability of material.Reducing Cr is in order to obtain higher thermal conductivity.
Summary of the invention
At the defective that prior art exists, the objective of the invention is a kind of high thermal conductance high abrasion hot stamping die with steel and preparation method.Its objective is the proportioning that adopts a kind of simple Chemical Composition, coordinated the proportioning of C and W, V, Mo formation carbide.Adopt 1080 ℃ of quenchings, make the abundant solid solution of alloying element, reach the purpose of the Key Performance Indicators such as thermal conductivity, wear resistance, hardness, impelling strength and anti-temper resistance that improve material.From saving the angle of Financial cost, adopt C, Mo, three kinds of elements of W, V as main alloy element, keep low Mn, low Cr, ultralow Si content, fully reduce element such as Si to the influence of thermal conductivity, make this patent steel possess high thermal conductivity.Main Mo, V, the W element of adding, make the carbide that forms the complexity of a large amount of W, V, Mo in the tissue of material reach strengthening effect, the carbide of these three kinds of elements can guarantee its toughness again on the intensity based that increases steel, and can make steel obtain that good temper resistance, red hardness, heat resistance, particularly W, V can form alloy carbide and the wear resistance that increases steel.Thereby a kind of have high heat conductance, high rigidity, high-wearing feature, good anti-temper resistance and the low-cost economical hot stamping die steel of good impelling strength have been developed.
For achieving the above object, the technical solution used in the present invention is as follows:
A kind of excessive heat conductance hot stamping die steel, the main following column element of its alloying constituent is formed (in the quality percentage composition):
C：0.45-0.50%；
Si：＜0.2%；
Mn：＜0.20%；
W：1.0-2.0%；
Mo：2.?5-3.5%；
Cr：＜0.30%；
V：0.5-1.0%
All the other are Fe and unavoidable impurities element, S in the impurity element :≤0.03%; P :≤0.03.
Below be the effect of main chemical elements of the present invention:
C?0.45~0.5%
Carbon is mainly to be that form with carbide exists.It is little when the matrix with solid solution to the damage ratio of the steel capacity of heat transmission when carbon exists with the second phase form, it can make strong carbide and the weak carbide of manganese enter the carbide from matrix, thereby raising thermal conductivity, therefore this patent is coordinated the composition proportion of carbon and tungsten, vanadium, molybdenum, make it all form carbide, and unlikely carbon content is too high; Simultaneously, carbon is one of main chemical elements of high heat-intensity hot-work die steel, a carbon part enters the effect that matrix plays solution strengthening, another part then is to form carbide, the strong carbide that molybdenum and tungsten form can be separated out at high tempering process small and dispersed and be produced the secondary hardening phenomenon, and the carbide that vanadium and tungsten form can effectively increase wear resistance.The original relatively material 4Cr5MoSiV1 of the design's carbon content decreases, its objective is and obtain more ferrite matrix as far as possible, thereby improve thermal conductivity and toughness, and improve distribution and the character of the carbide in the microstructure of steel, improve rank and the distribution of the liquation carbide of steel.Therefore, if carbon content is higher than this composition design upper limit, will cause the formation of too much carbide and the segregation of tissue to produce, influence the impelling strength performance of steel, and particularly cause the ununiformity of the liquation carbide of steel seriously to make the impelling strength of steel reduce; But this composition Design scope that is lower than carbon also will cause carbon and other alloying elements in conjunction with the equivalent generation deviation that forms carbide, can not form stable molybdenum carbide, tungsten carbide and all kinds carbide compound action effectively, influence hardness, impelling strength and the high-temperature behavior of steel.
Si?<0.2%
Outer silicon electronic structure and Fe differ greatly, and studies show that it can seriously reduce the heat conductivility of steel, so the content of silicon are controlled below 2% among the design.Reduce silicone content, make macrostructure's homogenizing more, and can reduce the constitutional supercooling on the freezing interface when solidifying, plasticity and toughness increase.The Si solid solution strengthening effect is remarkable, do not form carbide, also be insoluble to other carbide, except the hardening capacity that improves steel, Si also helps to improve the dispersity of separating out alloy carbide in the high tempering process, the secondary hardening peak is increased, thereby Si is the effective element that improves the intensity of matrix and improve resistance to tempering, the effect of element silicon is can be so that steel martensitic decomposition in the process of tempering slows down, can in the drawing process of austenite after martensitic transformation, effectively hinder martensitic decomposition, this mainly is by suppressing growing up and enlarging the εTan Huawu stable region of εTan Huawu particle, having postponed the transformation of ε-carbide to θ-carbide.Silicon is postponed ε → θ and is changed, and can fully reduce the growth rate of cementite in drawing process in the steel, and Siliciumatom suppresses the alligatoring of growing up of θ phase from θ separated out and formed Siliciumatom mutually around the θ phase enrichment region; Silicon can effectively improve the anti-temper softening ability of steel in addition.
But, also can increase the weight of the decarburization susceptibility of steel when the silicon amount is too high, and make the overaging speed increase of carbide gathering and be difficult to control.In addition, silicon and manganese acting in conjunction make the high-temperature behavior of steel, obtain more significant raising as high temperature anti-temper softening performance and thermal fatigue property, and these are all favourable to hot-work die steel use properties and life-span.Comprehensive what time above, this patent adds a spot of Si.
Mn?＜0.20%
In steelmaking process, manganese can reduce red brittleness, is good reductor and sweetening agent.It and S and bigger avidity is arranged, can avoid forming low-melting sulfide FeS at crystal boundary, and exist with the higher MnS with certain plasticity of fusing point, thereby can prevent that the hot-short phenomenon that causes because of FeS from eliminating the harmful effect of sulphur, improve the hot workability of steel.Manganese dissolves in the hardening capacity that can improve steel in the austenite.Mn has the solution strengthening effect, thereby improves ferrite and austenitic intensity and hardness, though the too late carbon of its solid solution strengthening effect, phosphorus and silicon, it is to the almost not influence of ductility of steel.
Though manganese element is weak carbide forming element, can not form carbide reinforced effect, the adding of a certain amount of manganese element can promote the decomposition of cementite and postpone separating out and growing up of carbide, be conducive to the thermostability of steel.In addition, manganese element can cause the content of the residual austenite in the steel to increase with stable, can improve toughness and the thermal fatigue resistance of steel like this.
But the manganese too high levels promotes the poly-partially fragility that makes of harmful element to increase, and weakens the resistance to corrosion of steel, reduces heat conductivility, welding property etc., takes all factors into consideration its content control below 0.2%.
Cr?＜0.30?%
Though the chromium element can solid solution in ferrite, can form carbide again.And add the chromium element in the existing hot-work die steel mostly, the chromium carbide type is that Cr7C3 and Cr23C6 type carbide play the effect of strengthening matrix, and the control of this chromium element makes steel separate out stable disperse phase in the process of tempering, this disperse phase M7C3 and Cr23C6 not only can improve the anti-tempered performance of steel, and can make steel produce certain red hardness, improve the heat resistance of steel.But consider that when tempering temperature is higher than 600 ℃ the carbide of Cr is just assembled alligatoring rapidly, makes that the anti-tempering stabilization energy of steel is relatively poor, and aspect thermal conductivity, Cr content increases to be increased than W and Mo big to the thermal conductivity damage effect of steel.Therefore, the design in＜0.30% scope, mainly utilizes chromium content control the carbide of W and Mo to replace the effect of chromium carbide, can not only play the same effect, has also reduced the influence of the thermal conductivity of Cr and the cost of alloy that has reduced steel.
Mo：?2.5-3.5%
Molybdenum improves hardening capacity and heat resistance, reduces temper brittleness, increases temper resistance, crystal grain thinning.In tool steel, can improve red property.Molybdenum element is the strong carbide forming element, also is one of important chemical element in the design of the design's composition, and the molybdenum element addition in the design is in the 2.5-3.5% scope.Because the solid solubility temperature of molybdenum is not high, just solid solution in a large number during low temperature quenching, and in the process of tempering separating out with parallel fine acicular (two dimension is the synusia shape) on the subgrain boundary of form in martensite lath of M2C, keep coherence with matrix, improve the hot hardness of steel.Therefore, by improving Mo content in the steel, in the answer that improves tempered martensite, recrystallization temperature, Mo can form comparatively tiny carbide in steel, thereby further improves heat resistance and the thermostability of material.The adding of molybdenum element has improved the hardening capacity of the austenitic stability of steel and steel, and in the drawing process of steel and carbon in conjunction with forming separating out of a fairly large number of more stable M2C alloy carbide, this precipitation process is that a kind of particle strengthening phase of disperse is separated out, comparatively be evenly distributed in the matrix of steel, have age hardening effect preferably.The control of the add-on of molybdenum obtains more M2C alloy carbide in this scope makes the process of steel in tempering, and produces the effect of twice bigger reinforcement, and this plays an important role to the hardness of steel and the raising of impelling strength.In addition, add tungsten in this patent, make molybdenum and tungsten form multiple complicated carbide, not only increased the intensity of steel, also increased anti-temper resistance and the heat resistance of steel.
W：1.?0~2.0%
The effect of tungsten mainly is temper resistance, red hardness, the heat resistance that increases steel and forms alloy carbide and increase its wear resistance, add molybdenum and W elements in this patent, make to form a large amount of molybdenums in the tissue of material and the carbide of tungsten carries out build up, and be conducive to improve thermal conductivity.
V：0.5%-1.0%
V element is the strong carbide forming element, and the strengthening effect in steel is similar with W elements, can improve wear resistance, can also hinder grain growth simultaneously, plays the effect of crystal grain thinning.In order to obtain high wear resistance, in order to coordinate the ratio of carbide, V is controlled at 0.5%-1.0% simultaneously.
P?≤0.03%
In the ordinary course of things, phosphorus is the harmful element in the steel, increases the fragility of steel, reduces the impelling strength of steel, so phosphoric control is the smelting requirements of the strictness of present technique steel, can certain influence be arranged desired value to rigidity.
S?≤0.03%
Sulphur mainly is present in the steel with the form of sulfide.It is generally acknowledged that sulphur is one of harmful element in the steel.Sulphur is easy to segregation in steel, worsen the quality of steel.When existing as the form with the lower FeS of fusing point, will cause the hot-short phenomenon of steel.Element sulphur causes the deterioration of the processing characteristics of steel easily on certain degree, make steel produce overheated and burn-off phenomenon easily in hot worked process.Continuous forging processing when therefore controlling processing characteristics and the mechanical property that sulphur content can guarantee steel, particularly diameter and forging the machine hammer cogging produce superheating phenomenon play the effect of drawing up.And the improvement of the microstructure of hot-work die steel played a role.
A kind of excessive heat conductance hot stamping die is with the preparation method of steel, and for the preparation of above-mentioned excessive heat conductance hot stamping die steel, present method adopts following steps:
(a) melting: alloy carries out melting by the method that tradition is conventional after pressing the mentioned component design, and the admixtion in the above-mentioned prescription is positioned in the electric furnace, carries out melting in the temperature more than 1500 ℃; Pour into a mould steel ingot then, it is stand-by to enter next step;
(b) esr: electroslag remelting process is voltage 50V, electric current 2800A, molten fast 11mm/min, pool depth 50mm, ESR ingot specification Φ 120.The content of gas and inclusion be can reduce behind the esr, and uniform ingredients, dense structure, steel ingot that quality is high obtained;
(c) annealing: in 700 ℃～900 ℃ the insulation 8 hours after furnace cooling;
(d) high-temperature homogenization: above-mentioned steel ingot is heated to 1235～1250 ℃, and is incubated 8～10 hours, make the composition of steel homogenizing, prevent component segregation, improve the solidified structure of material, cool off with being placed in the air;
(e) forge: steel ingot is heated to 1200～1230 ℃, carries out multiway forging, 900 ℃～950 ℃ of final forging temperatures, and forging ratio should be greater than 6; Forging rear annealing: in 800 ℃～860 ℃ annealing 8 hours, furnace cooling;
(f) annealing: above-mentioned steel forgings blank is put into process furnace, is heated to 660～700 ℃, the insulation 20-26h, after stove is chilled to 200 ℃ then again air cooling to room temperature;
Thermal treatment process: 1060 ℃～1100 ℃ quenchings, 560 ℃～640 ℃ tempering 3 times, each tempering 2h; Must allow more alloying element be solidly soluted in the matrix in order to obtain higher thermal conductivity, so quenching temperature fixes at least 1060 ℃.
More than; Finally obtain novel high heat conductance hot stamping die material.
Compared with prior art, the present invention has following outstanding advantage:
The present invention relates to a kind of novel high heat conductance high-wearing feature hot stamping die material, on the alloying thinking, the characteristics of steel of the present invention are simple alloyings, based on C, Mo, V and four kinds of elements of W; Secondly, keep lower Mn, ultralow Si, Cr element, make this patent steel possess high thermal conductivity and wear resistance; This also can save Financial cost.The performance of steel of the present invention is: through 1080 ℃ of quenchings, hardness is 54.9HRC, is 55.5HRC through 200 ℃ of tempering 2h hardness; Be 55.1HRC through 300 ℃ of tempering 2h hardness; Be 53.9HRC through 400 ℃ of tempering 2h hardness; Be 54.7HRC through 500 ℃ of tempering 2h hardness; Be 54HRC through 520 ℃ of tempering 2h hardness; Be 55.9HRC through 540 tempering 2h hardness; Be 55.5HRC through 560 ℃ of tempering 2h hardness; Be 56.9HRC through 580 ℃ of tempered-hardnesses; Be 57.9 through 600 ℃ of tempering 2h hardness; Be 56.7 through 620 ℃ of tempering 2h hardness; Be 51.8HRC through 640 ℃ of tempering 2h hardness.Has excellent temper resistance.Behind+560 ℃ tempering 2h+580 ℃ tempering 2h+600 ℃ tempering 2h of 1080 ℃ of quenchings, hardness can reach 56HRC, exceeds nearly 8 HRC than H13, can improve the wear resisting property of mould, can effectively prevent the plucking of die surface; Under 1080 ℃ of high temperature, quench, make alloying element be solidly soluted in the matrix fully, thermal conductivity with superelevation, see Table 1, thermal conductivity compares to existing H13 steel and exceeds closely 31% in the time of 700 ℃, exceeds 53% in the time of 400 ℃, is nearly 2 times of H13 in the time of 200 ℃, this can accelerate the punching press beat greatly and improve productivity effect, increases productivity effect; Wear resisting property is much improved than the H13 steel.
The thermal conductivity of table 1 differing temps lower inlet H13, homemade H13 and invention steel (W/ (m*k))
| |
100 | 200 | 300 | 400 | 500 | 600 | 700 |
| H13 | 22.24 | 23.72 | 24.49 | 25.4 | 25.56 | 27.36 | 25.44 |
| The invention steel | 44.56 | 43 | 40.33 | 38.76 | 35.53 | 36.3 | 33.2 |
Steel of the present invention has good machinability through after electrosmelting → esr → annealing → high-temperature homogenization → forging → annealing; After Overheating Treatment (quenching+high tempering), steel of the present invention has good hot hardness, and has high thermal conductivity, has high wear resistance.
Description of drawings
Fig. 1 is the contrast of the thermal conductivity of the common at each temperature H13 hot-work die steel of embodiment 1 and steel of the present invention;
Fig. 2 is the microstructure of embodiment 2 high heat conductance high abrasion hot stamping die steel quenching attitudes;
Fig. 3 is the microstructure of embodiment 2 high heat conductance high abrasion hot stamping die steel tempering attitudes;
Fig. 4 organizes for embodiment 3 tempering attitudes and observes W, V and Mo carbide and energy spectrum analysis under the SEM Electronic Speculum.
Fig. 5 is the 17 power spectrum ultimate analyses of Fig. 4 point.
Fig. 6 is example 3 high heat conductance hot stamping die steel HDCM3 tempering attitude stereoscan photographs.
Embodiment
Now specific embodiments of the invention are described in down by reference to the accompanying drawings.
Embodiment 1
Present embodiment has been produced a kind of steel, and its concrete composition is as follows:
C：0.45%；
Si：0.15%；
Mn：0.12%；
W：?2.55%；
Mo：2.6%；
Cr：0.18%；
V：0.67%；
All the other are Fe and unavoidable impurities element, S in the impurity element :≤0.03%; P :≤0.03%;
Preparation technology and thermal treatment process are as follows:
(a) melting: alloy carries out melting by the method that tradition is conventional after pressing the mentioned component design, and the admixtion in the above-mentioned prescription is positioned in the electric furnace, carries out melting 1530 ℃ temperature; Pour into a mould steel ingot then, it is stand-by to enter next step;
(b) esr: voltage 50V, electric current 2800A, molten fast 11mm/min, pool depth 50mm, ESR ingot specification Φ 120.The content of gas and inclusion be can reduce behind the esr, and uniform ingredients, dense structure, steel ingot that quality is high obtained;
(c) annealing: in 900 ℃ the insulation 8 hours after furnace cooling;
(d) high-temperature homogenization: above-mentioned steel ingot is heated to 1250 ℃, and is incubated 10 hours, make the composition of steel homogenizing, prevent component segregation, improve the solidified structure of material, cool off with being placed in the air;
(e) forge: steel ingot is heated to 1230 ℃, carries out multiway forging, 950 ℃ of final forging temperatures, and forging ratio should be greater than 6; Forging rear annealing: in 860 ℃ of annealing 8 hours, furnace cooling;
(f) annealing: above-mentioned steel forgings blank is put into process furnace, is heated to 700 ℃, the insulation 25h, after stove is chilled to 200 ℃ then again air cooling to room temperature;
(g) thermal treatment process: 1080 ℃ of insulations were quenched 560-2h+580-2h+600-2h tempering three times in 45 minutes; Under the thermal treatment process condition of recommending, hardness value is 57HRC, and notched bar impact strength is 110-130J.
(h) be illustrated in figure 1 as the thermal conductivity test result, in the time of 200 ℃, thermal conductivity is 43 W/(m*K), in the time of 700 ℃, thermal conductivity is 33.2 W/(m*K).Raise with temperature, the thermal conductivity of this patent steel reduces gradually, but thermal conductivity exceeds nearly 31% than H13 steel in the time of 700 ℃.
Present embodiment has been produced a kind of steel, and its concrete composition is as follows:
C：0.50%；
Si：0.08%；
Mn：0.?15%；
W：?1.8%；
Mo：2.5%；
Cr：0.08%；
V：0.8%；
All the other are Fe and unavoidable impurities element, S in the impurity element :≤0.05%; P :≤0.03%;
Preparation technology and thermal treatment process are as follows:
(a) melting: alloy carries out melting by the method that tradition is conventional after pressing the mentioned component design, and the admixtion in the above-mentioned prescription is positioned in the electric furnace, carries out melting in the temperature more than 1500 ℃; Pour into a mould steel ingot then, it is stand-by to enter next step;
(b) esr: electroslag remelting process is voltage 50V, electric current 2800A, molten fast 11mm/min, pool depth 50mm, ESR ingot specification Φ 120.The content of gas and inclusion be can reduce behind the esr, and uniform ingredients, dense structure, steel ingot that quality is high obtained;
(c) annealing: in 800 ℃ the insulation 8 hours after furnace cooling;
(d) high-temperature homogenization: above-mentioned steel ingot is heated to 1250 ℃, and is incubated 10 hours, make the composition of steel homogenizing, prevent component segregation, improve the solidified structure of material, cool off with being placed in the air;
(e) forge: steel ingot is heated to 1230 ℃, carries out multiway forging, 950 ℃ of final forging temperatures, and forging ratio should be greater than 6; Forging rear annealing: in 860 ℃ of annealing 8 hours, furnace cooling;
(f) annealing: above-mentioned steel forgings blank is put into process furnace, is heated to 700 ℃, the insulation 25h, after stove is chilled to 200 ℃ then again air cooling to room temperature;
(g) thermal treatment process: 1080 ℃ of insulations were quenched 560-2h+600-2h+620-2h tempering three times in 45 minutes; Under the thermal treatment process condition of recommending, hardness value is 56HRC, and notched bar impact strength is 120-150J.
(h) be illustrated in figure 1 as the thermal conductivity test result, in the time of 200 ℃, thermal conductivity is 44.2 W/(m*K), in the time of 700 ℃, thermal conductivity is 34.2 W/(m*K).
Embodiment 3
Present embodiment has been produced a kind of steel, and its concrete composition is as follows:
C：0.48%；
Si：0.12%；
Mn：0.?15%；
W：?1.8%；
Mo：2.7%；
Cr：0.18%；
V：0.54%；
All the other are Fe and unavoidable impurities element, S in the impurity element :≤0.03%; P :≤0.03%;
Preparation technology and thermal treatment process are as follows:
(a) melting: alloy carries out melting by the method that tradition is conventional after pressing the mentioned component design, and the admixtion in the above-mentioned prescription is positioned in the electric furnace, carries out melting in the temperature more than 1500 ℃; Pour into a mould steel ingot then, it is stand-by to enter next step;
(b) esr: electroslag remelting process is voltage 50V, electric current 2800A, molten fast 11mm/min, pool depth 50mm, ESR ingot specification Φ 120.The content of gas and inclusion be can reduce behind the esr, and uniform ingredients, dense structure, steel ingot that quality is high obtained;
(c) annealing: in 900 ℃ the insulation 8 hours after furnace cooling;
(d) high-temperature homogenization: above-mentioned steel ingot is heated to 1235 ℃, and is incubated 10 hours, make the composition of steel homogenizing, prevent component segregation, improve the solidified structure of material, cool off with being placed in the air;
(e) forge: steel ingot is heated to 1210 ℃, carries out multiway forging, 950 ℃ of final forging temperatures, and forging ratio should be greater than 6; Forging rear annealing: in 860 ℃ of annealing 8 hours, furnace cooling;
(f) annealing: above-mentioned steel forgings blank is put into process furnace, is heated to 680 ℃, the insulation 24h, after stove is chilled to 200 ℃ then again air cooling to room temperature;
(g) thermal treatment process: 45 minutes quenching 560-2h+600-2h+640-2h of 1080 ℃ of insulations tempering three times; Under the thermal treatment process condition of recommending, hardness value is 52HRC, and notched bar impact strength is 160-180J.
(h) be illustrated in figure 1 as the thermal conductivity test result, in the time of 200 ℃, thermal conductivity is 42.4W/(m*K), in the time of 700 ℃, thermal conductivity is 32.2 W/(m*K).
Claims (3)
1. an excessive heat conductance hot stamping die steel is characterized in that the main following column element composition of alloying constituent, in quality percentage composition: C:0.45-0.50%; Si:＜0.2%; Mn＜0.2%; W:1.0-2.0%; Mo:2. 5-3.5%; Cr:＜0.2%; V:0.5-1.0%; All the other are Fe and unavoidable impurities element.
2. according to the described a kind of excessive heat conductance hot stamping die steel of claim, it is characterized in that the tempered-hardness of this steel is at 56-57HRC, thermal conductivity is 32～33.5W/(m*K) in the time of 700 ℃ in the time of 200 ℃ 42～44.5W/(m*K).
3. an excessive heat conductance hot stamping die is with the preparation method of steel, for the preparation of according to the described excessive heat conductance of claim hot stamping die steel, and present method employing following steps:
(a) melting: by excessive heat conductance hot stamping die Steel Alloy composition, in quality percentage composition: C:0.45-0.50%; Si:＜0.2%; Mn＜0.20%; W:1.0-2.0%; Mo:2. 5-3.5%; Cr:＜0.20%; V:0.5-1%; All the other are Fe and unavoidable impurities element; Carry out melting by the method that tradition is conventional, admixtion is positioned in the electric furnace, carry out melting in the temperature more than 1500 ℃; Pour into a mould steel ingot then, next step is stand-by;
(b) esr: voltage 50V, electric current 2800A, molten fast 11mm/min, pool depth 50mm, ESR ingot specification Φ 120; The content of gas and inclusion be can reduce behind the esr, and uniform ingredients, dense structure, steel ingot that quality is high obtained;
(c) annealing: in 700 ℃～900 ℃ the insulation 8 hours after furnace cooling;
(d) high-temperature homogenization: above-mentioned steel ingot is heated to 1235～1250 ℃, and is incubated 8～10 hours, make the composition of steel homogenizing, prevent component segregation, improve the solidified structure of material, cool off with being placed in the air;
(e) forge: steel ingot is heated to 1200～1230 ℃, carries out multiway forging, 900 ℃～950 ℃ of final forging temperatures, and forging ratio should be greater than 6; Forging rear annealing: in 800 ℃～860 ℃ annealing 8 hours, furnace cooling;
(f) annealing: above-mentioned steel forgings blank is put into process furnace, is heated to 660～700 ℃, the insulation 20-26h, after stove is chilled to 200 ℃ then again air cooling to room temperature;
(g) thermal treatment process: 1060 ℃～1100 ℃ quenchings, 560 ℃～640 ℃ tempering 3 times, each tempering 2h; Finally obtain the wear-resisting hot stamping die alloy steel material of heat resistance.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2013102413729A CN103334052A (en) | 2013-06-18 | 2013-06-18 | High-thermal conductivity high-abrasion resistance hot stamping die steel and preparation method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2013102413729A CN103334052A (en) | 2013-06-18 | 2013-06-18 | High-thermal conductivity high-abrasion resistance hot stamping die steel and preparation method thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN103334052A true CN103334052A (en) | 2013-10-02 |
Family
ID=49242247
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2013102413729A Pending CN103334052A (en) | 2013-06-18 | 2013-06-18 | High-thermal conductivity high-abrasion resistance hot stamping die steel and preparation method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN103334052A (en) |
Cited By (18)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103898283A (en) * | 2014-03-25 | 2014-07-02 | 宁夏共享集团有限责任公司 | Tempering heat treatment process of high-strength steel |
| CN103993223A (en) * | 2014-05-06 | 2014-08-20 | 上海大学 | Ultrahigh thermal conductivity wear-resistant hot stamping die steel and manufacturing method thereof |
| CN104313462A (en) * | 2014-09-28 | 2015-01-28 | 宝山钢铁股份有限公司 | High wear-resistant hot-stamping die steel and manufacturing method thereof |
| CN105002337A (en) * | 2015-07-21 | 2015-10-28 | 北京奥普科星技术有限公司 | H13 die steel heat treating method and H13 die steel obtained through same |
| CN108774712A (en) * | 2018-06-21 | 2018-11-09 | 河南中原特钢装备制造有限公司 | Superelevation thermal conductivity hot stamping die steel and its manufacturing method |
| CN109457168A (en) * | 2018-12-24 | 2019-03-12 | 宁波颂杰电器有限公司 | Household gas range fuel gas conduit alloy and preparation method thereof and fuel gas conduit |
| CN109518084A (en) * | 2018-12-07 | 2019-03-26 | 南京工业职业技术学院 | A kind of high heat conductance is containing Al, Nb nitriding hot die steel and preparation method thereof |
| CN110468345A (en) * | 2019-08-29 | 2019-11-19 | 江苏大学 | A kind of hot die steel of high abrasion |
| CN111850393A (en) * | 2020-06-29 | 2020-10-30 | 河北工业职业技术学院 | Bainite die steel and preparation method thereof |
| CN111902558A (en) * | 2018-03-27 | 2020-11-06 | 株式会社神户制钢所 | Steel sheet for hot stamping |
| CN112501520A (en) * | 2020-12-03 | 2021-03-16 | 上海工程技术大学 | Impact-resistant and smashing-resistant wear-resistant steel and preparation method thereof |
| CN112725688A (en) * | 2020-11-25 | 2021-04-30 | 河钢股份有限公司 | Cold and hot dual-purpose steel for thread rolling die and preparation method thereof |
| CN113151732A (en) * | 2020-01-07 | 2021-07-23 | 武汉昆伦特钢装备科技开发有限公司 | High-strength high-temperature-resistant and low-temperature-resistant special gold steel and manufacturing process thereof |
| CN114318124A (en) * | 2020-09-29 | 2022-04-12 | 宝山钢铁股份有限公司 | Ultrahigh wear-resistant high-toughness hot-work die steel and preparation method thereof |
| CN114395738A (en) * | 2022-01-18 | 2022-04-26 | 河北工业职业技术学院 | Die steel with high thermal diffusivity and preparation method thereof |
| CN114908301A (en) * | 2019-03-01 | 2022-08-16 | 育材堂（苏州）材料科技有限公司 | Hot work die steel, heat treatment method thereof and hot work die |
| CN115216700A (en) * | 2022-08-01 | 2022-10-21 | 马鞍山钢铁股份有限公司 | 1700 MPa-level steel for fasteners and production method and heat treatment process thereof |
| CN117026068A (en) * | 2023-10-08 | 2023-11-10 | 中北大学 | Investment precision casting ferrite stainless steel and preparation method and application thereof |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2008056982A (en) * | 2006-08-30 | 2008-03-13 | Daido Steel Co Ltd | Die steel having excellent thermal fatigue property |
| CN102212753A (en) * | 2011-01-14 | 2011-10-12 | 上海大学 | Novel heat and abrasion resistant alloy steel material for hot stamping die |
| CN102373376A (en) * | 2010-08-18 | 2012-03-14 | 宝山钢铁股份有限公司 | High-silicon high-manganese hot-work die steel and preparation method thereof |
| CN102676923A (en) * | 2012-05-29 | 2012-09-19 | 上海大学 | Steel with ultra-high thermal conductivity for hot-stamping die and preparation method of steel |
-
2013
- 2013-06-18 CN CN2013102413729A patent/CN103334052A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2008056982A (en) * | 2006-08-30 | 2008-03-13 | Daido Steel Co Ltd | Die steel having excellent thermal fatigue property |
| CN102373376A (en) * | 2010-08-18 | 2012-03-14 | 宝山钢铁股份有限公司 | High-silicon high-manganese hot-work die steel and preparation method thereof |
| CN102212753A (en) * | 2011-01-14 | 2011-10-12 | 上海大学 | Novel heat and abrasion resistant alloy steel material for hot stamping die |
| CN102676923A (en) * | 2012-05-29 | 2012-09-19 | 上海大学 | Steel with ultra-high thermal conductivity for hot-stamping die and preparation method of steel |
Cited By (22)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103898283B (en) * | 2014-03-25 | 2016-06-15 | 宁夏共享集团有限责任公司 | A kind of tempering heat treatment process of high strength steel |
| CN103898283A (en) * | 2014-03-25 | 2014-07-02 | 宁夏共享集团有限责任公司 | Tempering heat treatment process of high-strength steel |
| CN103993223A (en) * | 2014-05-06 | 2014-08-20 | 上海大学 | Ultrahigh thermal conductivity wear-resistant hot stamping die steel and manufacturing method thereof |
| CN104313462A (en) * | 2014-09-28 | 2015-01-28 | 宝山钢铁股份有限公司 | High wear-resistant hot-stamping die steel and manufacturing method thereof |
| CN105002337A (en) * | 2015-07-21 | 2015-10-28 | 北京奥普科星技术有限公司 | H13 die steel heat treating method and H13 die steel obtained through same |
| CN111902558A (en) * | 2018-03-27 | 2020-11-06 | 株式会社神户制钢所 | Steel sheet for hot stamping |
| CN108774712A (en) * | 2018-06-21 | 2018-11-09 | 河南中原特钢装备制造有限公司 | Superelevation thermal conductivity hot stamping die steel and its manufacturing method |
| CN109518084A (en) * | 2018-12-07 | 2019-03-26 | 南京工业职业技术学院 | A kind of high heat conductance is containing Al, Nb nitriding hot die steel and preparation method thereof |
| CN109457168B (en) * | 2018-12-24 | 2021-07-06 | 宁波正直科技有限公司 | Gas pipe alloy of household gas stove, preparation method thereof and gas pipe |
| CN109457168A (en) * | 2018-12-24 | 2019-03-12 | 宁波颂杰电器有限公司 | Household gas range fuel gas conduit alloy and preparation method thereof and fuel gas conduit |
| CN114908301A (en) * | 2019-03-01 | 2022-08-16 | 育材堂（苏州）材料科技有限公司 | Hot work die steel, heat treatment method thereof and hot work die |
| CN110468345A (en) * | 2019-08-29 | 2019-11-19 | 江苏大学 | A kind of hot die steel of high abrasion |
| CN113151732A (en) * | 2020-01-07 | 2021-07-23 | 武汉昆伦特钢装备科技开发有限公司 | High-strength high-temperature-resistant and low-temperature-resistant special gold steel and manufacturing process thereof |
| CN111850393B (en) * | 2020-06-29 | 2021-09-07 | 河北工业职业技术学院 | Bainite die steel and preparation method thereof |
| CN111850393A (en) * | 2020-06-29 | 2020-10-30 | 河北工业职业技术学院 | Bainite die steel and preparation method thereof |
| CN114318124A (en) * | 2020-09-29 | 2022-04-12 | 宝山钢铁股份有限公司 | Ultrahigh wear-resistant high-toughness hot-work die steel and preparation method thereof |
| CN112725688A (en) * | 2020-11-25 | 2021-04-30 | 河钢股份有限公司 | Cold and hot dual-purpose steel for thread rolling die and preparation method thereof |
| CN112501520A (en) * | 2020-12-03 | 2021-03-16 | 上海工程技术大学 | Impact-resistant and smashing-resistant wear-resistant steel and preparation method thereof |
| CN114395738A (en) * | 2022-01-18 | 2022-04-26 | 河北工业职业技术学院 | Die steel with high thermal diffusivity and preparation method thereof |
| CN115216700A (en) * | 2022-08-01 | 2022-10-21 | 马鞍山钢铁股份有限公司 | 1700 MPa-level steel for fasteners and production method and heat treatment process thereof |
| CN117026068A (en) * | 2023-10-08 | 2023-11-10 | 中北大学 | Investment precision casting ferrite stainless steel and preparation method and application thereof |
| CN117026068B (en) * | 2023-10-08 | 2023-12-22 | 中北大学 | Investment precision casting ferrite stainless steel and preparation method and application thereof |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103334052A (en) | High-thermal conductivity high-abrasion resistance hot stamping die steel and preparation method thereof | |
| CN102676923A (en) | Steel with ultra-high thermal conductivity for hot-stamping die and preparation method of steel | |
| CN103993223A (en) | Ultrahigh thermal conductivity wear-resistant hot stamping die steel and manufacturing method thereof | |
| CN101538686B (en) | Martensite precipitation hardening stainless steel for structural member and manufacturing method thereof | |
| CN107974636A (en) | A kind of high rigidity high-hardenability pre-hardening plastic die steel and preparation method thereof | |
| CN102605261A (en) | Hot stamping mould steel and method for manufacturing same | |
| CN104046915A (en) | Large-section high-performance hot work die steel for die casting and preparation technology thereof | |
| CN104313462A (en) | High wear-resistant hot-stamping die steel and manufacturing method thereof | |
| CN102212756A (en) | Chromium-molybdenum-vanadium hotwork tool-die steel and heat treatment process thereof | |
| CN102650020A (en) | High-silicon high-manganese type high-thermal stability hot work die steel and thermal treatment process thereof | |
| CN105002433B (en) | A kind of cavitation-preventive age-hardening bloom plastic die steel and preparation method thereof | |
| CN102691005B (en) | Low alloy die steel | |
| CN102534391A (en) | Hot-work die steel for extrusion wheel and manufacturing method thereof | |
| CN101440456B (en) | Hot die steel with excellent heat resistance and high toughness | |
| CN105274437A (en) | Thermal fatigue resisting and high performance hot working die steel and manufacturing process thereof | |
| CN102373376B (en) | High-silicon high-manganese hot-work die steel and preparation method thereof | |
| CN101353770A (en) | High strength stainless gear steel and preparation thereof | |
| CN102653837A (en) | High-toughness wear-resistant cold-working die steel and preparation method thereof | |
| CN105002439A (en) | Wear-resistant steel with 400-level Brinell hardness and manufacturing method thereof | |
| CN105018854A (en) | High-heat-resistance hot work die steel and preparation method | |
| CN109735777A (en) | A kind of anti-oxidant hot die steel and preparation method thereof | |
| CN109182669B (en) | High-hardness high-toughness easy-welding pre-hardened plastic die steel and preparation method thereof | |
| CN102021493A (en) | Hot rolled steel plate for precision stamping and manufacturing method thereof | |
| CN101942606B (en) | Nitrogen alloyed austenitic hot work die steel and preparation method thereof | |
| CN102260823B (en) | Economic high-strength steel plate with yield strength of 690MPa, and manufacture method thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C12 | Rejection of a patent application after its publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20131002 |