Background technology
Hammer mill is industries such as metallurgy, mine, building materials and electric power disintegrating apparatus commonly used, tup is wherein main vulnerable part, its operation principle is to rely on the tup of rotation at a high speed to clash into the purpose that enters the material in the cracking cabin and reach comminuting matter, and the main failure forms of tup is wearing and tearing and fracture.For a long time, the wear resistence of grinder hammerhead is poor, and service life is short, changes frequently, is the key factor of restriction material crush efficiency.Therefore development of new hammer head material and shape technology becomes problem demanding prompt solution the service life of improving tup.
The grinder hammerhead of present domestic employing mainly contains the monoblock cast tup: related material has potassium steel (Mnl3), medium carbon alloy steel (Chinese invention patent CNl050566A), abrasion resistant Mn-W-Ti casting steel (Chinese invention patent CNl068637C), low-alloy steel (40CrMnSiMoRe), high carbon chromium nickel-molybdenum alloy steel and rich chromium cast iron etc.; Composite hammer head: comprise double-fluid double metal composite casting tup, castingin or inlay or the box-like tup of soldering group (Chinese utility model patent CN2257218Y, CN2564248Y); Surface overlaying or whole built-up welding tup (Chinese invention patent CNl419990A, CNl517173A).For monoblock cast steel alloy tup, although it has high obdurability, is difficult for rupturing in running, because the integral hardness of tup is lower, and no hard exists mutually in the tissue, so wear no resistance, service life is short.Although people attempt to improve the wear resistence of tup by adjusting measures such as alloying component and improvement Technology for Heating Processing, consequently manufacturing cost significantly increases, and the wear resistence raising is very little; For monoblock cast rich chromium cast iron tup, easy fracture in service then is the main cause of its premature failure; So-called composite hammer head, be meant with a kind of material of high rigidity such as rich chromium cast iron or carbide alloy and a kind of steel alloy with obdurability or carbon steel by composite casting, weld or method such as inlay and combine and be made into tup, wherein improving the wear resistence of tup, and the obdurability material prevents the fracture of tup to high hardness material as the hammer handle of tup as the scope of attack of tup.This class tup manufacturing process complexity, cost height (all the more so) for carbide alloy, and technology stability is poor, defective such as easily crack, stress is concentrated at binding site, therefore being in operation tends to take place two kinds of materials and separates from the junction, causes the premature failure of tup; The built-up welding tup is to adopt the special antiwear welding rod to have the wearing course of high rigidity at the end of steel alloy or carbon steel tup (scope of attack or working face) built-up welding one deck, its shortcoming is the bead-welding technology complexity, technique controlling difficulty is big, have a large amount of micro-cracks in the overlay cladding, be mingled with, defective such as pore, therefore overlay cladding in service to peel off and fall piece be its main failure forms.
The steel alloy tup of this company of West Germany uncle power turtledove and the rich chromium cast iron-low-carbon alloy steel composite casting tup of Japanese river island company are arranged in the world, and the former wearability is relatively poor, and the latter is because composite casting is prone to the iron and steel break-off.
Summary of the invention
The objective of the invention is to overcome the shortcoming of above-mentioned prior art, a kind of wear resistence height is provided, easy fracture and peeling off not in the use, composite bed and metal carrier body are the composite material hammer head and the casting method thereof of metallurgical binding.
For achieving the above object, the technical solution used in the present invention is: at first adopt electro-smelting metal carrier body material to form molten metal, the tapping temperature of molten metal is 1500 ℃~1680 ℃, and pouring temperature is 1380 ℃~1500 ℃; With WC (tungsten carbide) particle of 150~800 μ m and binding agent by 3~4: the mass ratio of l mixes makes paste, during moulding with the end face side of this paste material-paving at the die cavity of tup mould, form preformed layer after the oven dry down at 150 ℃~200 ℃, start the vertical centrifugal casting machine, the rotating speed of vertical centrifugal casting machine is controlled at 50~200 rev/mins, the molten metal cast of coming out of the stove, poring rate is 5~28kg/s, molten metal enters the casting mold die cavity by down gate during cast, and down gate also is the turning cylinder of centrifuge rotating disk simultaneously;
The addition of WC particle is calculated according to following formula:
W=S·h·f
v·ρ
In the formula: W is the weight g of WC particle;
S is the surface area mm of tup end face (working face or the scope of attack)
2
H is the thickness 6~20mm of composite bed;
f
vVolume fraction 18%~52% for WC particle in the composite bed;
ρ is the density g/mm of WC particle
3
Rotating speed with the vertical centrifugal casting machine after cast finishes is increased to 500~900r/min, rotates 3~l0min, shuts down cooling and gets final product.
Metal carrier body material of the present invention is potassium steel, steel alloy or ordinary carbon steel; The hardness of WC particle is 2500~3000Hv, and density is 15.8~16.5g/mm
3It is 10~20% heat curing-type water soluble phenol resin, 5~10% borax that binding agent contains mass percent, the mixture of 3% 300 order aluminium powders, 2% 270 order high-carbon chromium irons and 2% 270 order molybdenum-iron powder, and surplus is a water.
Composite material hammer head according to casting method casting of the present invention, the hammer body of tup is potassium steel, steel alloy or ordinary carbon steel, the hammer tip of tup is that the working face or the scope of attack are the WC particle reinforced composite, and composite layer hardness is HRC55~67, and thickness is 6-20mm.
The composite material hammer head that adopts preparation method of the present invention to obtain has excellent impact wear resistance; Composite layer hardness is HRC55~67, the composite layer thickness is 6-20mm, WC particle is excellent metallurgical with the interface of matrix and combines in the interface of composite layer and metal carrier body and the composite layer, the bond strength height, WC particle is evenly distributed, and the grain volume fraction adjustable extent is 18%~52%; The hammer head of hammer crusher that the present invention produces, its life-span is 5~10 times of traditional potassium steel tup; The PLJ formula disintegrating machine jet liner plate (a kind of form of tup) that the present invention produces, its life-span is 3~6 times of Cr20 rich chromium cast iron.
The specific embodiment
Below in conjunction with accompanying drawing the present invention is described in further detail.
Embodiment 1: referring to Fig. 1, at first adopt 250kg medium-frequency induction furnace melting potassium steel to form molten metal, the tapping temperature of molten metal is 1500 ℃, and pouring temperature is 1380 ℃; With hardness is 2500~3000Hv, and density is 15.8~16.5g/mm
3Granularity is that the WC particle of 150~800 μ m is 10% heat curing-type water soluble phenol resin with containing mass percent, 10% borax, 3% 300 order aluminium powders, the mixture of 2% 270 order high-carbon chromium irons and 2% 270 order molybdenum-iron powder, to be the bonding agent made of water by 3: 1 mass ratio mix surplus makes paste, the end face side of the die cavity 4 of the tup mould of during moulding this paste material-paving being made at resin sand 2, form preformed layer 1 after the oven dry down at 200 ℃, start the vertical centrifugal casting machine, the rotating speed of vertical centrifugal casting machine is controlled at 200 rev/mins, the molten metal cast of coming out of the stove, poring rate is 23kg/s, molten metal enters the casting mold die cavity by down gate 3 during cast, and down gate 3 also is the turning cylinder of centrifuge rotating disk simultaneously;
The addition of WC particle is calculated according to following formula:
W=S·h·f
v·ρ
In the formula: W is the weight g of WC particle;
S is the surface area mm of tup end face (working face or the scope of attack)
2
H is the thickness 6~20mm of composite bed;
f
vVolume fraction 18%~52% for WC particle in the composite bed;
ρ is the density g/mm of WC particle
3
Rotating speed with the vertical centrifugal casting machine after cast finishes is increased to 900r/min, rotates 3min, shuts down cooling and gets final product.
Embodiment 2: at first adopt 250kg medium-frequency induction furnace molten alloy steel to form molten metal, the tapping temperature of molten metal is 1580 ℃, and pouring temperature is 1450 ℃; With hardness is 2500~3000Hv, and density is 15.8~16.5g/mm
3Granularity is that the WC particle of 150~800 μ m is 20% heat curing-type water soluble phenol resin with containing mass percent, 8% borax, 3% 300 order aluminium powders, the mixture of 2% 270 order high-carbon chromium irons and 2% 270 order molybdenum-iron powder, to be the bonding agent made of water by 4: 1 mass ratio mix surplus makes paste, the end face side of the die cavity 4 of the tup mould of during moulding this paste material-paving being made at water-glass sand 2, form preformed layer 1 after the oven dry down at 180 ℃, start the vertical centrifugal casting machine, the rotating speed of vertical centrifugal casting machine is controlled at 160 rev/mins, the molten metal cast of coming out of the stove, poring rate is 5kg/s, molten metal enters the casting mold die cavity by down gate 3 during cast, and down gate 3 also is the turning cylinder of centrifuge rotating disk simultaneously;
The addition of WC particle is calculated according to following formula:
W=S·h·f
v·ρ
In the formula: W is the weight g of WC particle;
S is the surface area mm of tup end face (working face or the scope of attack)
2
H is the thickness 6~20mm of composite bed;
f
vVolume fraction 18%~52% for WC particle in the composite bed;
ρ is the density g/mm of WC particle
3
Rotating speed with the vertical centrifugal casting machine after cast finishes is increased to 700r/min, rotates 6min, shuts down cooling and gets final product.
Embodiment 3: at first adopt 250kg medium-frequency induction furnace melting ordinary carbon steel to form molten metal, the tapping temperature of molten metal is 1620 ℃, and pouring temperature is 1470 ℃; With hardness is 2500~3000Hv, and density is 15.8~16.5g/mm
3Granularity is that the WC particle of 150~800 μ m is 15% heat curing-type water soluble phenol resin with containing mass percent, 5% borax, 3% 300 order aluminium powders, the mixture of 2% 270 order high-carbon chromium irons and 2% 270 order molybdenum-iron powder, to be the bonding agent made of water by 3.2: 1 mass ratio mix surplus makes paste, the end face side of the die cavity 4 of the tup mould of during moulding this paste material-paving being made at resin sand 2, form preformed layer 1 after the oven dry down at 175 ℃, start the vertical centrifugal casting machine, the rotating speed of vertical centrifugal casting machine is controlled at 130 rev/mins, the molten metal cast of coming out of the stove, poring rate is 17kg/s, molten metal enters the casting mold die cavity by down gate 3 during cast, and down gate 3 also is the turning cylinder of centrifuge rotating disk simultaneously;
The addition of WC particle is calculated according to following formula:
W=S·h·f
v·ρ
In the formula: W is the weight g of WC particle;
S is the surface area mm of tup end face (working face or the scope of attack)
2
H is the thickness 6~20mm of composite bed;
f
vVolume fraction 18%~52% for WC particle in the composite bed;
ρ is the density g/mm of WC particle
3
Rotating speed with the vertical centrifugal casting machine after cast finishes is increased to 500r/min, rotates 10min, shuts down cooling and gets final product.
Embodiment 4: at first adopt 250kg medium-frequency induction furnace melting potassium steel to form molten metal, the tapping temperature of molten metal is 1680 ℃, and pouring temperature is 1500 ℃; With hardness is 2500~3000Hv, and density is 15.8~16.5g/mm
3Granularity is that the WC particle of 150~800 μ m is 13% heat curing-type water soluble phenol resin with containing mass percent, 7% borax, 3% 300 order aluminium powders, the mixture of 2% 270 order high-carbon chromium irons and 2% 270 order molybdenum-iron powder, to be the bonding agent made of water by 3.5: 1 mass ratio mix surplus makes paste, the end face side of the die cavity 4 of the tup mould of during moulding this paste material-paving being made at water-glass sand 2, form preformed layer 1 after the oven dry down at 160 ℃, start the vertical centrifugal casting machine, the rotating speed of vertical centrifugal casting machine is controlled at 50 rev/mins, the molten metal cast of coming out of the stove, poring rate is 28kg/s, molten metal enters the casting mold die cavity by down gate 3 during cast, and down gate 3 also is the turning cylinder of centrifuge rotating disk simultaneously;
The addition of WC particle is calculated according to following formula:
W=S·h·f
v·ρ
In the formula: W is the weight g of WC particle;
S is the surface area mm of tup end face (working face or the scope of attack)
2
H is the thickness 6~20mm of composite bed;
f
vVolume fraction 18%~52% for WC particle in the composite bed;
ρ is the density g/mm of WC particle
3
Rotating speed with the vertical centrifugal casting machine after cast finishes is increased to 800r/min, rotates 4min, shuts down cooling and gets final product.
Embodiment 5: at first adopt 250kg medium-frequency induction furnace molten alloy steel to form molten metal, the tapping temperature of molten metal is 1520 ℃, and pouring temperature is 1410 ℃; With hardness is 2500~3000Hv, and density is 15.8~16.5g/mm
3Granularity is that the WC particle of 150~800 μ m is 18% heat curing-type water soluble phenol resin with containing mass percent, 9% borax, 3% 300 order aluminium powders, the mixture of 2% 270 order high-carbon chromium irons and 2% 270 order molybdenum-iron powder, to be the bonding agent made of water by 3.8: 1 mass ratio mix surplus makes paste, the end face side of the die cavity 4 of the tup mould of during moulding this paste material-paving being made at resin sand 2, form preformed layer 1 after the oven dry down at 150 ℃, start the vertical centrifugal casting machine, the rotating speed of vertical centrifugal casting machine is controlled at 70 rev/mins, the molten metal cast of coming out of the stove, poring rate is 20kg/s, molten metal enters the casting mold die cavity by down gate 3 during cast, and down gate 3 also is the turning cylinder of centrifuge rotating disk simultaneously;
The addition of WC particle is calculated according to following formula:
W=S·h·f
v·ρ
In the formula: W is the weight g of WC particle;
S is the surface area mm of tup end face (working face or the scope of attack)
2
H is the thickness 6~20mm of composite bed;
f
vVolume fraction 18%~52% for WC particle in the composite bed;
ρ is the density g/mm of WC particle
3
Rotating speed with the vertical centrifugal casting machine after cast finishes is increased to 600r/min, rotates 8min, shuts down cooling and gets final product.
The present invention relies on action of centrifugal force, and molten metal is penetrated in the hole of preformed layer, thereby forms surface composite layer at the outer surface (tup end face) of foundry goods.One of effect of binding agent has been the effect of bonding WC particle, makes it have good laying, can guarantee again after the oven dry that preformed layer has enough intensity; Two of effect is the wetabilitys that promote molten metal and WC particle, improves the infiltration ability of molten metal; Three of effect is the oxide inclusion defectives that can effectively eliminate in the composite bed, improves the composite bed metallurgical quality.Wherein phenolic resins provides necessary adhesion strength, borax can partly be eliminated the defective that the iron oxide on the interface is piled up between metallic matrix and the particle, auxiliary material aluminium powder, high-carbon chromium iron and molybdenum-iron powder can partly be eliminated the defective that the iron oxide on the interface is piled up between metallic matrix and the particle, can improve the tissue and the performance of the matrix material in the composite simultaneously.
Hammer body according to the composite material hammer head that preparation method of the present invention obtained is potassium steel, steel alloy or ordinary carbon steel, the hammer tip of tup is that the working face or the scope of attack are the WC particle reinforced composite, composite layer hardness is HRC55~67, thickness is 6-20mm, has excellent impact wear resistance; WC particle is excellent metallurgical with the interface of matrix and combines in the interface of composite layer and metal carrier body and the composite layer, the bond strength height, and WC particle is evenly distributed, and the grain volume fraction adjustable extent is 18%~52%; The hammer head of hammer crusher that the present invention produces, its life-span is 5~10 times of traditional potassium steel tup; The PLJ formula disintegrating machine jet liner plate of producing (a kind of form of tup), its life-span is 3~6 times of Cr20 rich chromium cast iron.