CN102168217A - Mechanical uniform dispersion method of iron 15 copper-3 graphite semi-solid state slurry - Google Patents

Abstract

The invention discloses a mechanical uniform dispersion method of iron 15 copper-3 graphite semi-solid slurry, which belongs to the research field of mechanical uniform dispersion of iron 15 copper-3 graphite semi-solid slurry. The invention adopts a mechanical preparation method and uses double blades The first-layer mechanical agitator can mechanically and uniformly disperse the iron-15 copper-3 graphite semi-solid slurry under the condition that the radians of the upper and lower double-sided arc-shaped straight blades are 60-62° and 30-32° respectively. To achieve uniform distribution of graphite particles, the uniform dispersion time can be shortened to 8 minutes and 20 seconds.

Description

A kind of mechanical uniform dispersion method of iron 15 copper-3 graphite semi-solid slurry

technical field

The invention relates to a method for mechanically uniformly dispersing iron-15copper-3 graphite semi-solid slurry.

Background technique

Publication number: CN1888801A, title of invention: "A mechanical stirring preparation method of QTi3.5-10 graphite semi-solid slurry", expounds the mechanical preparation method of QTi3.5-10 graphite semi-solid slurry, that is, using mechanical stirring The circumferential movement and downward movement generated when the double-sided arc-shaped straight blades of the device rotate are used to break the primary solid phase formed during the solidification of the QTi3.5 titanium bronze melt, and the upper part of the double-sided arc-shaped straight blades is continuously The graphite particles are dispersed into the lower QTi3.5 titanium bronze melt. When the circumferential motion state of the QTi3.5 titanium bronze melt is close to the circumferential motion state of double-sided arc-shaped straight blades, the dispersion effect of graphite particles becomes poor. , the mechanical stirrer changes the direction of rotation, and uses the arc on the other side of the double-sided arc-shaped straight blade to disperse the graphite particles on the upper part of the double-sided arc-shaped straight blade into the lower QTi3.5 titanium bronze melt; with the help of mechanical stirring The up and down movement control device of the device is used to drive the mechanical stirrer to move up and down continuously, so that the graphite particles floating on the upper part of the graphite crucible are dispersed into the QTi3.5 titanium bronze melt within the entire range of the crucible to obtain a uniform graphite particle distribution QTi3.5-10 graphite semi-solid slurry. In this mechanical preparation method, the mechanical agitator is a single-blade mechanical agitator, which uses a single-layer blade, and within the effective contact range between the blade and the semi-solid slurry, the graphite particles are continuously dispersed by means of the blade. Graphite particles are dispersed into the semi-solid slurry. Under the condition that the arc of the concave arc surface of the single-layer double-sided arc-shaped straight blade of the mechanical agitator disclosed in the patent CN1888801A is 40-90°, the single-blade mechanical agitator and its up-and-down movement After the control device runs for 10 to 15 minutes to uniformly disperse, the QTi3.5-10 graphite semi-solid slurry with uniform distribution of graphite particles can be obtained.

Iron 15 copper is an iron alloy with a copper content of 15wt%. Iron 15 copper-3 graphite semi-solid slurry is a semi-solid slurry containing 3wt% graphite particles and 97wt% primary solid phase particles and liquid phase. CN1888801A patented method, Under the condition that the arc of the concave arc surface of the single-layer double-sided arc-shaped straight blade of the disclosed mechanical stirrer is 40-90°, it needs to be uniformly dispersed for 10-13 minutes to obtain the iron-15-copper-3 graphite half with graphite particles evenly distributed. solid slurry.

For the preparation of iron 15 copper-3 graphite semi-solid slurry, under the premise of achieving uniform distribution of graphite particles, the running time of the mechanical stirrer and its up and down movement control device, that is, the shorter the uniform dispersion time, the smaller the energy consumption and the higher the cost. Low, and the iron 15 copper-3 graphite semi-solid slurry is less polluted and its quality is higher, so the uniform dispersion time of the iron 15 copper-3 graphite semi-solid slurry that can achieve uniform distribution of graphite particles is shorter and better good.

Contents of the invention

The technical problem to be solved by the present invention is to overcome the deficiency of "long uniform dispersion time" in the existing mechanical preparation method, and provide a method that can quickly realize the uniform dispersion of graphite particles in iron 15 copper-3 graphite semi-solid slurry, further shortening the Uniform dispersion time to achieve uniform distribution of graphite particles.

The technical solution adopted by the present invention to solve the technical problem is: adopt the mechanical preparation method, utilize the double-blade layer mechanical agitator, and the radians of the concave arc surface of the double-sided arc-shaped straight blades on the upper and lower layers are 60-62° and 30-32° respectively Under certain conditions, the semi-solid slurry of iron 15 copper-3 graphite is uniformly dispersed.

The beneficial effects of the invention are: for the particles in the melt, if the particles in the melt are to be dispersed in the melt as soon as possible, the dispersion strength must be strengthened. In the semi-solid slurry mechanical preparation method, if after the single-layer blade disperses the particles in the semi-solid slurry, and then uses another layer of blades to implement the second dispersion, then the particle size in the semi-solid slurry The dispersion effect will be significantly improved, and the uniform dispersion time for uniform particle distribution will be further shortened. The present invention uses the continuous secondary dispersion of the double-layer blades after the optimized combination of the upper and lower double-sided arc-shaped straight blades with concave arc surface radians to further promote The uniform distribution of graphite particles in the semi-solid slurry is achieved, thereby achieving the purpose of shortening the uniform dispersion time. Utilizing the present invention, the iron-15-copper-3 graphite semi-solid slurry is uniformly dispersed, and the uniform dispersion time for uniform distribution of graphite particles can be shortened to 8 minutes and 20 seconds, which is at least shorter than the shortest uniform dispersion time of 10 minutes using the CN1888801A patent method up 16%.

Description of drawings

Fig. 1 is the front view of the device for uniformly dispersing iron 15 copper-3 graphite semi-solid slurry by the method of the present invention.

In the figure, circular stirring rod 1, double-sided curved straight blade 2, ceramic crucible 3, heating pipe 4, cooling pipe 5, iron 15 copper-3 graphite semi-solid slurry 6, plug 7, upper cover 8, Ar air pipe 9. Underframe 11, bearing bush 12, thrust bearing 13, motor 14, gear transmission mechanism 15, guide plate 16, guide groove 17, rack 18, motor 19, transmission mechanism 20, up travel switch 21, down travel switch 22 , bracket 23.

Fig. 2 is an A-A view of a device for uniformly dispersing iron-15 copper-3 graphite semi-solid slurry by the method of the present invention.

In the figure, thermocouple 10.

Fig. 3 is a B-B partial view of a device for uniformly dispersing iron-15 copper-3 graphite semi-solid slurry by the method of the present invention.

Fig. 4 is the microstructure of the iron 15 copper-3 graphite semi-solid slurry obtained after uniformly dispersing the iron 15 copper-3 graphite semi-solid slurry by the method of the present invention.

Detailed ways

In conjunction with the accompanying drawings, the specific description of the graphite particle device in the method of the present invention for uniformly dispersing iron 15 copper-3 graphite semi-solid slurry is as follows:

The device for uniformly dispersing graphite particles in Fe-15Cu-3 graphite semi-solid slurry includes: mechanical stirrer and its driving and up-and-down movement control device, ceramic crucible 3, upper cover 8, plug 7, Ar gas pipe 9 and thermocouple 10.

The ceramic crucible 3 is fixed on the base frame 11 by means of mechanical connection, and the heating pipes 4 and the cooling pipes 5 are uniformly distributed in the wall, and are respectively connected with the external power supply and the cooling liquid supply system.

The mechanical stirrer is a double-blade mechanical stirrer, which is composed of a circular stirring rod 1 and two upper and lower blade layers. The material is heat-resistant ceramics. The lower end of the circular stirring rod 1 is square, and its four sides match the circular stirring rod 1 Cut, the upper and lower blade layers are located at the square lower end of the circular stirring rod 1, and the interval a is 20mm. In each of the upper and lower blade layers, there are four double blades with the same shape and corresponding distribution except that the concave arc surface is different. Surface arc-shaped straight blades 2, the four double-sided arc-shaped straight blades 2 of the lower layer are located at the lower part of the square lower end of the circular stirring rod 1, and its roots are perpendicular to the four surfaces of the square lower end of the circular stirring rod 1, forming a 90° angle to each other. °, the width is the same as the diameter of the circular stirring rod 1, the concave arc surfaces on the left and right sides of the double-sided arc-shaped straight blades 2 face downward, symmetrically distributed, and are arc-shaped, and the radian is 30-32°. The upper surface of the double-sided arc-shaped straight blade 2 is tangent, the intersection line of the lower part of the concave arc-shaped surface and the lower end surface of the square lower end of the circular stirring rod 1 are located in the same horizontal plane, and the outer end of the double-sided arc-shaped straight blade 2 and the inner wall of the ceramic crucible 3 The distance between them is 5mm; the four double-sided curved straight blades 2 of the upper layer are located on the upper part of the square lower end of the circular stirring rod 1, and the arc of the concave arc is 60-62°. The surface and the upper end face of the square lower end of the circular stirring rod 1 are located in the same horizontal plane.

The driving device of mechanical stirrer is made of motor 14, gear transmission mechanism 15 and positioning mechanism. The positioning mechanism is located on the upper part of the circular stirring rod 1, and the horizontal positioning is carried out by the upper and lower two bearing bushes 12, and the longitudinal positioning is carried out by the upper and lower thrust bearings 13. The motor 14, the gear transmission mechanism 15 and the positioning mechanism of the mechanical agitator driving device respectively The mechanical connection is fixed on the guide plate 16 , and the guide plate 16 can move up and down in the guide groove 17 fixed on the bracket 23 .

The up and down movement control device of the mechanical agitator is made of a motor 19, a transmission mechanism 20, an upper stroke switch 21 and a lower stroke switch 22. The transmission mechanism 20 is composed of a rack 18, a gear, a worm gear, and a worm drive. The lower end of the rack 18 is mechanically connected to the guide plate 16 of the mechanical agitator drive device. The steering of the motor 19 is controlled by the upstroke switch 21 and the downstroke switch. 22 control, that is, when the upper double-sided arc-shaped straight blade 2 of the mechanical agitator moves upward to the top of the semi-solid slurry 6, the upper part of the rack 18 touches the downstroke switch 22, and the motor 19 changes the direction of rotation, so that the mechanical agitator Move downward; when the lower double-sided arc-shaped straight blade 2 of the mechanical stirrer moves down to the bottom of the ceramic crucible 3, the upper part of the rack 18 touches the upstroke switch 21, and the motor 19 changes the direction to make the mechanical stirrer move upward. The motor 19, the transmission mechanism 20, the upstroke switch 21, and the downstroke switch 22 of the mechanical stirrer's up and down movement control device are fixed on the support 23 by mechanical connection.

The Ar gas tube 9 is fixed in the hole of the upper cover 8 , the thermocouple 10 is fixed in the side wall of the ceramic crucible 3 , and its end is in contact with the semi-solid slurry 6 , and the plug 7 is located at the bottom of the ceramic crucible 3 .

The power of the mechanical stirrer is 5kW, the mechanical stirrer changes the direction of rotation every 1 to 3 minutes, the rotating speed is 3 to 5 revolutions per second, and the continuous up and down movement speed of the mechanical stirrer is controlled at 5 to 20mm/s.

A mechanical uniform dispersion method for iron 15 copper-3 graphite semi-solid slurry, using the circular motion and downward movement generated when the double-sided arc-shaped straight blades of the mechanical stirrer rotate to break the solidification of iron 15 copper melt The primary solid phase formed during the process, and continuously disperses the graphite particles on the upper part of the double-sided arc-shaped straight blade into the lower part of the iron-15 copper melt. When the circumferential movement state of the iron-15 copper melt is close to the double-sided arc When the dispersion effect of the graphite particles is deteriorated due to the circumferential movement of the blades, the mechanical agitator changes the direction of rotation, and uses the arc on the other side of the double-sided arc-shaped straight blades to disperse the graphite particles on the upper part of the double-sided arc-shaped straight blades. In the iron 15 copper melt in the lower part; and with the help of the up and down movement control device of the mechanical stirrer, the mechanical stirrer is driven to move up and down continuously, so as to disperse the graphite particles floating on the upper part of the crucible to the iron 15 In copper melt, obtain the iron 15 copper-3 graphite semi-solid slurry that graphite particle distributes evenly, comprise the following steps:

Step 1, preparing iron 15 copper melt, the temperature is controlled at 1500°C;

Step 2, pour the above-mentioned iron 15 copper melt and 230 mesh graphite particles into the ceramic crucible 3 according to the mass percentage of 97% and 3%, and the crucible is preheated to 1270 ° C by the heating tube 4 in its wall, and the upper cover is covered After 8, turn on Ar gas to prevent oxidation;

Step 3, start the mechanical stirrer and its up and down movement control device, stir the iron 15 copper melt and the graphite particles, at the same time, turn off the power supply of the heating tube 4 and connect the cooling water to the cooling tube 5 in the crucible wall for cooling After cooling the iron-15 copper melt to a uniform dispersion temperature of 1270-1320°C, turn off the cooling water, turn on and adjust the power supply of the heating pipe 4, so that the temperature of the iron-15 copper melt is stabilized at the uniform dispersion temperature, and after a certain period of uniform dispersion , to obtain iron 15 copper-3 graphite semi-solid slurry 6 with uniform structure.

Embodiment 1, when the rotation speed of the mechanical stirrer is 3 revolutions per second, the vertical movement speed is 5mm/s, the rotation direction is changed every 3 minutes, and the uniform dispersion temperature is 1270°C, the upper and lower sides of the double-bladed mechanical stirrer When the radians of the double-sided arc-shaped straight blades are 60° and 30° respectively, the uniform dispersion time of the iron-15copper-3 graphite semi-solid slurry with uniform distribution of graphite particles is 8 minutes and 20 seconds.

Embodiment 2, when the rotation speed of the mechanical stirrer is 5 rpm, the vertical movement speed is 15mm/s, the rotation direction is changed every 2 minutes, and the uniform dispersion temperature is 1270°C, the upper and lower sides of the double blade layer mechanical stirrer When the radians of the double-sided arc-shaped straight blades are 60° and 32° respectively, the uniform dispersion time of the iron-15copper-3 graphite semi-solid slurry with uniform distribution of graphite particles is 8 minutes and 10 seconds.

Embodiment 3, when the rotation speed of the mechanical stirrer is 4 rpm, the vertical movement speed is 20mm/s, the rotation direction is changed every 1 minute, and the uniform dispersion temperature is 1320°C, the upper and lower sides of the double-blade mechanical stirrer When the radians of the double-sided curved straight blades are 62° and 30° respectively, the uniform dispersion time of the iron 15 copper-3 graphite semi-solid slurry with uniform distribution of graphite particles is 8 minutes and 20 seconds.

Embodiment 4, when the rotation speed of the mechanical stirrer is 4 rpm, the vertical movement speed is 10mm/s, the rotation direction is changed every 2 minutes, and the uniform dispersion temperature is 1287°C, the upper and lower sides of the double blade layer mechanical stirrer When the radians of the double-sided arc-shaped straight blades are 61° and 31° respectively, the uniform dispersion time of the iron-15copper-3 graphite semi-solid slurry with uniform distribution of graphite particles is 8 minutes and 10 seconds.

Embodiment 5, when the rotation speed of the mechanical stirrer is 5 rpm, the vertical movement speed is 15mm/s, the rotation direction is changed every 3 minutes, and the uniform dispersion temperature is 1320°C, the upper and lower sides of the double-bladed mechanical stirrer When the radians of the double-sided arc-shaped straight blades are 62° and 32° respectively, the uniform dispersion time of the iron-15copper-3 graphite semi-solid slurry with uniform distribution of graphite particles is 8 minutes and 10 seconds.

It can be seen that under the condition that the radians of the upper and lower double-sided arc-shaped straight blades of the double-blade mechanical agitator are 60-62° and 30-32° respectively, the iron-15copper-3 graphite semi-solid slurry is mechanically uniform Dispersion, the uniform dispersion time to achieve uniform distribution of graphite particles can be shortened to 8 minutes and 20 seconds.

Accompanying drawing 4 is the microstructure of the iron 15 copper-3 graphite semi-solid slurry obtained after mechanically uniformly dispersing the iron-15 copper-3 graphite semi-solid slurry by the method of the present invention. The dark areas in the figure are graphite particles, the light areas are primary solid phase particles, and the other areas are post-generated solid phases. It can be seen that the distribution of graphite particles is very uniform. It can be seen that the present invention can quickly realize the uniform dispersion of graphite particles in the iron-15copper-3 graphite semi-solid slurry.

Claims (1)

1. the mechanical homodisperse method of iron 15 bronze medals-3 graphite semi-solid slurry, the circumferential movement that produces when utilizing the double side arc shaped straight blade rotation of mechanical stirrer and moving downward, smash the nascent solid phase that forms in the iron 15 copper melts process of setting, and constantly the graphite granule on double side arc shaped straight blade top is distributed in iron 15 copper melts of bottom, when the circumferential movement state of iron 15 copper melts causes the dispersion effect variation of graphite granule near double side arc shaped straight blade circumferential movement state, mechanical stirrer changes sense of rotation, and the arc that utilizes double side arc shaped straight blade opposite side is distributed to the graphite granule on double side arc shaped straight blade top in iron 15 copper melts of bottom; And the control device that moves up and down by means of mechanical stirrer, come the driving device agitator to move up and down continuously, thereby in whole crucible scope, the graphite granule that swims in crucible top is distributed in iron 15 copper melts, obtain iron 15 bronze medals-3 graphite semi-solid slurry that graphite granule is evenly distributed, may further comprise the steps:

Step 1, preparation iron 15 copper melts, temperature is controlled at 1500 ℃;

Step 2, the mass percent by 97% and 3% is poured above-mentioned iron 15 copper melts and 230 purpose graphite granules in the ceramic crucible into, crucible is preheating to 1270 ℃ by the heating tube in its wall, cover loam cake after, connect Ar gas with anti-oxidation;

Step 3, start mechanical stirrer and move up and down control device, iron 15 copper melts and graphite granule are stirred, simultaneously, close in the power supply of heating tube and the cooling tube in sidewall of crucible and to connect water coolant and cool off, after iron 15 copper melts are cooled to 1270～1320 ℃ of homodisperse temperature, close water coolant, open and regulate the power supply of heating tube, make iron 15 copper melts temperature-stables in this homodisperse temperature, behind the homodisperse certain hour, obtain iron 15 bronze medals-3 graphite semi-solid slurry of homogeneous microstructure;

It is characterized in that mechanical stirrer is a double leaf lamella mechanical stirrer, the double side arc shaped straight blade cancave cambered surface of its levels radian is respectively 60～62 ° and 30～32 °.

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