CN106521124A - Forked flattening, upsetting, and rolling H13 hot-working die steel homogenization forging technology - Google Patents

Abstract

The invention discloses a forked flattening, upsetting, and rolling H13 hot-working die steel homogenization forging technology. The technology comprises the following steps: step one, normal steel ingot heating: thoroughly heating a hot-working die normally heated ESR steel ingot by a gas stove to a temperature of 1240-1260 DEG C; step two, flattening: flattening the thoroughly heated steel ingot according to a ratio of X:Y:Z (thickness: width: height), returning the steel ingot to the gas stove, and thoroughly heating the steel ingot for 3 to 6 hours; and step three, upsetting: taking out the flattened blank from the gas stove, and upsetting the whole blank according to an upsetting ratio of 1.8-2.3. The technology has the advantages that the components are homogenized, large block carbides are grinded, the belt textures and mesh textures are refined, and the surface quality is improved.

Description

It is a kind of intersect open flat upsetting pull H13 class hot die steels and homogenize forging technology

Technical field

The present invention relates to the Technology for Heating Processing of iron and steel metallurgical industry hot die steel, refers in particular to H13 class alloy Forming Dies The Technology for Heating Processing that tool steel forging is made.

Background technology

Extruding and compression mod of the H13 classes mainly as non-ferrous metal, because its use environment is severe, its module is required to have compared with High mechanical property and structural homogenity.H13 class hot-work dies steel ingot is mainly existed using conventional Technology for Heating Processing at present 1200-1300 DEG C of insulation a few hours+High temperature diffusion process+multiway forging or multiple upsetting pull deformation technique+annealing process+height Temperature tempering heat treatment after forging, the undissolved carbide formed in the technical process and Segregation of Chemical Composition region can be along deformation processing sides Banding or desmachyme is formed to extension, and its microscopic structure generally existing carbide segregation, banding and desmachyme are serious Problem, before its quenching, spherodized structure and microstructure uniformity and center portion side knock work(majority can not meet NADCA207# Standard or SEP1614 standards require often occur the early failure phenomenas such as bridge cut-off cracking and surface checking in use.And Above-mentioned problem using suitable forging technology and Technology for Heating Processing, can eliminate microscopic structure generation in forging process Problem, so that realize the purpose of tissue and the double refinements of carbide.Therefore develop a kind of intersection and open flat upsetting pull H13 class hot die steels For the High temperature diffusion time is shortened, the forging technology that homogenizes realizes that composition homogenizes；Promote big massive carbide broken and refine Banding and desmachyme, improve surface quality；Strengthen quenching degree, plasticity and toughness and temper resistance；The throwing of mould steel can also be improved Optical property and machinability, so as to the cold-heat fatigue property and resistant to elevated temperatures intensity to improving steel ingot has important meaning Justice.

The content of the invention

Present invention aim to overcome that the not enough offer that above-mentioned H13 classes hot die steel normative heat treatment technique is present is a kind of Intersection is opened flat upsetting pull H13 class hot die steels and is homogenized forging technology.

It is a kind of intersect open flat upsetting pull H13 class hot die steels and homogenize forging technology, processing step is as follows：

Step one, steel ingot normal heating：Hot-work die normal heating electroslag ingot is heated to into 1250 by gas furnace ± 10 DEG C are burnt thoroughly；

Step 2, opens flat：Again by the steel ingot grilled thoroughly according to X: Y: Z (thickness: width: height) ratio carry out out it is flat, afterwards Melt down again 3-6 hours are grilled thoroughly at 1250 ± 10 DEG C；

Step 3, jumping-up：Flat slab will be ended coming out of the stove for the ratio of 1.8-2.3 in upset ratio carries out overall jumping-up；

Step 4, returns flat；X, Y-direction (i.e. wide and thick exchange) will be exchanged i.e. according to Y: X by right-angled intersection principle after jumping-up: The ratio upsetting flat of Z, returns and pulls out same size jumping-up slab, melt down again afterwards and grill thoroughly 3-6 hours at 1250 ± 10 DEG C；

Step 5, then jumping-up：Flat slab will be ended coming out of the stove for the ratio of 1.8-2.3 in upset ratio carries out overall jumping-up；

Step 6, cross-circulation：Repeat step two, step 3, number of repetition depend on the accumulation forging on three-dimensional Deformation rate：

Step 7, pulling shaping：The slab after flat jumping-up will be opened to pull out to product requirement size Jing cross-circulation；

Step 8：Miniaturization heat treatment after forging.

Used as improvement project, in step 2, X: Y: Z is 1: 1.2-1.4: 2.5-2.7.

Used as improvement project, the accumulation forging deformation rate in step 6 is defined as follows：

That is forging material of the forging press at steel ingot or the same position of steel billet after the pressure of X-direction i ＆ lt be highlyAnd from ingot To in material deformation process, direction pressure number of times is n；

The accumulation forging deformation rate computing formula of Y and Z-direction is as follows in the same manner：

The control of accumulation forging deformation rate exists。

The present invention is had the following advantages compared with prior art：

1) steel ingot carries out melting down High temperature diffusion after cross-circulation opens flat upsetting pull in the case where accumulation forging deformation rate is accurately calculated, and one Aspect is conducive to blank center portion to burn thoroughly as heat exchange surface area increases completely with surface to center portion Distance Shortened, and heat-transfer effect is good； , for the as-cast structure of steel ingot, its crystal grain is tiny and vacancy concentration and dislocation for the plastic deformation tissue of another aspect slab Density is big, can accelerate the High temperature diffusion process of Elements Atom and realize homogenization of composition in the short period of time.

2) opening flat predeformation makes the big block primary carbide of steel ingot center tentatively be crushed, and comes from aerodynamic point Say that dissolving of the primary carbide of fragmentation during high temperature flashes back is accelerated, and high temperature deformation and High temperature diffusion are alternately It is more beneficial for accelerating this process that homogenizes.

3) deformation slab accelerates diffusion process by changing ingotism area size and distribution, and its Forging Plasticity becomes Shape direction is symmetrical and deformation extent is controllable, after coordinating suitable forging miniaturization process can obtain even tissue it is tiny it is high to Property H13 mould steel forging materials.

4) present invention strengthens quenching degree, plasticity and toughness and the temper resistance of mould steel, also improves the polishability of mould steel Energy, machinability and cold-heat fatigue property, so that improve the service life of finished product die steel.

Description of the drawings

Fig. 1 for intersect open flat upsetting pull H13 class hot die steels homogenize forging technology process after die-casting module center Microstructure.

Fig. 2 be intersect open flat upsetting pull H13 class hot die steels homogenize forging technology process after hot extruding die bar The microstructure of center.

Specific embodiment

Embodiment 1

It is a kind of intersect open flat upsetting pull H13 hot die steels and homogenize forging technology, its heat treatment process is as follows：1) steel Ingot normal heating：Average diameter is passed through using 1250 DEG C of normal heatings of gas furnace for 6.59 tons of electroslag ingots of φ 600；2) open It is flat：Again by the steel ingot grilled thoroughly according to X: the ratio of Y: Z (thickness: width: height)=1: 1.25: 2.5 carries out out flat (i.e. 630mm × 790mm × 1700mm), melt down again afterwards 4 hours are grilled thoroughly at 1250 DEG C；3) jumping-up：To end in the ratio that upset ratio is 2.0 Flat slab is come out of the stove carries out overall jumping-up；4) return flat；By after jumping-up by be rotated by 90 ° exchange X, Y-direction (i.e. wide 790mm and thickness 630mm is exchanged) flat 790mm × 630mm × 1700mm is pulled out, melt down again afterwards 4 hours are grilled thoroughly at 1250 DEG C；5) jumping-up again：By upsetting The thick ratio than for 2.0 will end flat slab comes out of the stove carries out overall jumping-up；6) pulling shaping：By return it is flat after slab pull out to Product cross dimensions (260mm × 730mm × Lmm), now the accumulated deformation rate on forging three-dimensional: 100%-120%.

；7) miniaturization heat treatment after forging.

Accumulation forging deformation rate is defined as follows：

That is forging material of the forging press at steel ingot or the same position of steel billet after the pressure of X-direction i ＆ lt be highlyAnd from ingot To in material deformation process, direction pressure number of times is n；

The accumulation forging deformation rate computing formula of Y and Z-direction is as follows in the same manner：

Now forging center portion take test block through quenching be tempered to hardness HRC44-46 and be processed into size for 7mm × 10mm × 55mm impact specimens, the ballistic work test result of its three-dimensional >=280J, be shown in Table shown in 1, it is specific intersect open flat forging After making PROCESS FOR TREATMENT, the microstructure of die-casting module center is as shown in figure 1, GA3 ranks are required in reaching SEP1614 standards.

1260 × 730 section die-casting module centric(al) impact work(measured value (quench and be tempered to hardness HRC44-46) of table

Sampling direction	Actual measurement number 1/J	Actual measurement number 2/J	Actual measurement number 3/J	Actual measurement number 4/J	Actual measurement number 5/J
						X-direction	282	280	282	284	290
Y direction	286	288	290	290	287
						Z-direction	287	288	282	289	298

Embodiment 2

It is a kind of intersect open flat upsetting pull H13 hot die steels and homogenize forging technology, as different from Example 1, step 2, Open flat：Again by the steel ingot grilled thoroughly according to X: the ratio of Y: Z (thickness: width: height)=1: 1.2: 2.5 carries out out flat, Zhi Houzai Melt down 6 hours are grilled thoroughly at 1250 DEG C；

Accumulated deformation rate：120%-150%.

Now forging center portion take test block through quenching be tempered to hardness HRC44-46 and be processed into size for 7mm × 10mm × 55mm impact specimens, the ballistic work test result of its three-dimensional >=280J, be shown in Table shown in 2, reach in SEP1614 standards GA3 ranks are required.

2 260 × 730 section die-casting module centric(al) impact work(measured value (quench and be tempered to hardness HRC44-46) of table

Embodiment 3

It is a kind of intersect open flat upsetting pull H13 hot die steels and homogenize forging technology, as different from Example 1, step 2, Open flat：Again by the steel ingot grilled thoroughly according to X: the ratio of Y: Z (thickness: width: height)=1: 1.4: 2.7 carries out out flat, Zhi Houzai Melt down 3 hours are grilled thoroughly at 1250 DEG C；

Accumulated deformation rate：130%-140%.

Now forging center portion take test block through quenching be tempered to hardness HRC44-46 and be processed into size for 7mm × 10mm × 55mm impact specimens, the ballistic work test result of its three-dimensional >=280J, be shown in Table shown in 3, reach in SEP1614 standards GA3 ranks are required.

3 260 × 730 section die-casting module centric(al) impact work(measured value (quench and be tempered to hardness HRC44-46) of table

Sampling direction	Actual measurement number 1/J	Actual measurement number 2/J	Actual measurement number 3/J	Actual measurement number 4/J	Actual measurement number 5/J
						X-direction	284	280	284	282	293
Y direction	287	282	295	285	282
						Z-direction	281	284	284	281	291

Embodiment 4

It is a kind of intersect open flat upsetting pull H13 class hot die steels and homogenize forging technology, its heat treatment process is as follows：

1) steel ingot normal heating：WillThe electroslag ingot of net weight 3580kg is heated to 1250 DEG C thoroughly using gas furnace Burn；2) open flat：Again by the steel ingot grilled thoroughly according to X: the ratio of Y: Z (thickness: width: height)=1: 1.3: 2.5 carry out out it is flat extremely 515mm × 670mm × 1330mm, melts down again afterwards and grills thoroughly 5 hours at 1250 DEG C；3) jumping-up：In the ratio that upset ratio is 2.0 Slab is come out of the stove carries out overall jumping-up；4) return flat；To be rotated by 90 ° after jumping-up Exchange) upsetting pulls out for flat time to 670mm × 515mm × 1330mm, melts down again afterwards and grill thoroughly 5 hours at 1250 DEG C；5) jumping-up again：By upsetting The thick ratio than for 2.0 will end flat slab comes out of the stove carries out overall jumping-up；6) open flat：Open it is flat to 515mm × 670mm × 1330mm, melts down again afterwards and grills thoroughly 3 hours at 1250 DEG C；7) jumping-up again：Flat slab will be ended in the ratio that upset ratio is 2.0 Coming out of the stove carries out overall jumping-up, and now the accumulation forging deformation rate on X and Y direction is close to 100% and the accumulation forging in Z-direction Deformation rate is made for 150%；8) pulling shaping：The slab after flat jumping-up will be opened to pull out to product requirement size Jing cross-circulation9) miniaturization heat treatment after forging：Concrete technology refers to a kind of middle carbon Cr-Mo-V series hot die steel Tissue miniaturization pretreating process, CN 104178612A now take test block in forging center portion and Jing quench temper to HRC44- Between 46, machining specimen size is the non-notch impact specimen of 7mm × 10mm × 55mm, surveys the impact of its three-dimensional Work(>=320j, it is specific intersect open microstructure after flat forging technology is processed at extrusion die module centers as shown in Fig. 2 reaching To in SEP1614 standards, GA2 ranks are required.

Claims (3)

1. it is a kind of intersect open flat upsetting pull H13 class hot die steels and homogenize forging technology, it is characterised in that the processing step is as follows：

Step one, steel ingot normal heating：Hot-work die normal heating electroslag ingot is heated to into 1250 ± 10 DEG C by gas furnace Burn thoroughly；

Step 2, opens flat：Again by the steel ingot grilled thoroughly according to X: Y: Z ratio carry out out it is flat, melt down again afterwards 1250 ± 10 DEG C burn Saturating 3-6 hours；

Step 3, jumping-up：Flat slab will be ended coming out of the stove for the ratio of 1.8-2.3 in upset ratio carries out overall jumping-up；

Step 4, returns flat；Will after jumping-up by right-angled intersection principle exchange X, Y-direction, i.e., according to Y: X: Z ratio upsetting flat, return Same size jumping-up slab is pulled out, and is melted down again afterwards and 3-6 hours is grilled thoroughly at 1250 ± 10 DEG C；

Step 5, then jumping-up：Flat slab will be ended coming out of the stove for the ratio of 1.8-2.3 in upset ratio carries out overall jumping-up；

Step 6, cross-circulation：Repeat step two, step 3, number of repetition depend on the accumulation forging deformation on three-dimensional Rate；

Step 7, pulling shaping：The slab after flat jumping-up will be opened to pull out to product requirement size Jing cross-circulation；

Step 8, miniaturization heat treatment after forging.

2. forging technology according to claim 1, it is characterised in that：In described step two, X: Y: Z is 1: 1.2-1.4: 2.5-2.7。

3. the forging technology according to any one of claims 1 to 3, it is characterised in that：Accumulation forging in described step six Make deformation rate to be defined as follows：

${\mathrm{\Ψ}}_x=\underset{i=1}{\overset{n}{\Σ}}\frac{L_x^{i-1}-L_x^i}{L_x^{i-1}}\×100\%=\underset{i=1}{\overset{n}{\Σ}}\frac{{\mathrm{\ΔL}}_x^i}{L_x^{i-1}}\×100\%;$

That is forging material of the forging press at steel ingot or the same position of steel billet after the pressure of X-direction i ＆ lt be highlyAnd from ingot to material In deformation process, direction pressure number of times is n；

The accumulation forging deformation rate computing formula of Y and Z-direction is as follows in the same manner：

${\mathrm{\Ψ}}_y=\underset{i=1}{\overset{n}{\Σ}}\frac{L_y^{i-1}-L_y^i}{L_y^{i-1}}\×100\%=\underset{i=1}{\overset{n}{\Σ}}\frac{{\mathrm{\ΔL}}_y^i}{L_y^{i-1}}\×100\%;$

${\mathrm{\Ψ}}_z=\underset{i=1}{\overset{n}{\Σ}}\frac{L_z^{i-1}-L_z^i}{L_z^{i-1}}\×100\%=\underset{i=1}{\overset{n}{\Σ}}\frac{{\mathrm{\ΔL}}_z^i}{L_z^{i-1}}\×100\%;$

The control of accumulation forging deformation rate exists