CN104786153A - Reverse ultrasonic assisted gas-liquid-solid three-phase abrasive particle flow polishing processing method and device - Google Patents

Abstract

The invention discloses a reverse ultrasonic assisted abrasive flow polishing processing method and device. The ultrasonic generating device is installed at a position opposite to the direction of the abrasive flow and forms an included angle with the direction of the abrasive flow to generate a The direction of the abrasive particle flow is opposite to that of the reverse ultrasonic wave that forms an angle with the direction of the abrasive particle flow. The above-mentioned reverse ultrasonic wave compresses the micro-sized bubbles near the workpiece processing surface in the abrasive flow medium containing micro-sized bubbles, causing the micro-sized bubbles to collapse. When the micro-sized bubbles collapse, a reverse micro-shock wave opposite to the direction of the abrasive flow will be generated. The micro-shock wave will cause a large pressure in the local area of the abrasive flow to produce a micro-explosion effect; the effect of the micro-explosion Two component forces are generated, the vertical component force is used to increase the contact probability and force between the abrasive grains and the raised peaks on the workpiece processing surface, and the reverse horizontal component force can form a relative retardation effect on the abrasive grains, increasing the interaction between the abrasive grains and the workpiece time, greatly improving the polishing efficiency of the abrasive flow.

Description

Reverse Ultrasonic Assisted Gas-Liquid-Solid Three-Phase Abrasive Flow Polishing Method and Device

technical field

The invention relates to the field of soft fluid surface grinding and polishing, and more specifically relates to a reverse ultrasonic-assisted gas-liquid-solid three-phase abrasive flow polishing method and device.

Background technique

In the high-tech fields such as modern optics, electronic information and thin film science, it is necessary to realize ultra-smooth surface manufacturing (Ultrasmooth Surface Manufacturing) on the surface of precision optical parts and functional crystal materials, such as soft X-ray optical system, laser gyro mirror, high-density wave Demultiplexer, high-energy laser mirror, functional optical device, optical window, etc.

The liquid-solid two-phase soft abrasive flow polishing process that appeared in the early stage is based on the turbulent flow of the abrasive flow, based on the collision between the abrasive particles and the collision between the abrasive particles and the wall, and the dynamics of the abrasive particles. Analysis, using the cutting effect of abrasive particles on the wall surface in the turbulent flow field, the rough part of the wall surface of the workpiece is precision polished.

The gas-liquid-solid three-phase abrasive flow polishing processing method is a new type of fluid polishing medium formed by uniformly mixing micro-sized bubbles into the liquid-solid two-phase abrasive flow in a certain proportion, forming a turbulent flow on the upper surface of the workpiece, using the The micro-explosion mechanism produced by bubble collapse drives the abrasive particles to cut the surface of the workpiece more efficiently, achieving the effect of polishing the workpiece efficiently.

At present, the flow channel used in the gas-liquid-solid three-phase abrasive flow polishing process adopts the method of single inlet and single outlet. The fluid flows in from the inlet of the flow channel, flows out from the outlet, and finally returns to the abrasive flow storage tank. According to the processing principle of three-phase abrasive particle flow, the abrasive particle flow for processing the workpiece must form a turbulent flow in the flow channel. In the turbulent flow, the randomness of the abrasive particle movement is conducive to surface disorder until the tool-free mirror level on the surface of the workpiece is achieved. processing effect. Based on the previous experimental conditions, the simple single-input-output processing channel has the following disadvantages: ① When the pressure or flow rate of the booster pump is low, the flow rate of the gas-liquid-solid three-phase abrasive flow output by the booster pump cannot reach the The minimum speed of turbulent flow causes the abrasive particle flow in the abrasive particle flow channel to be in a laminar flow state, which in turn leads to a low probability of micro-sized bubbles in the abrasive particle flow collapsing, and the processing effect is not obvious; ②The booster pump outputs the abrasive particle flow The flow velocity reaches the minimum speed for forming turbulent flow in the flow channel. The bubbles may collapse under the disturbance of turbulent flow, but they cannot collapse with a high probability in the area close to the surface of the workpiece, and thus cannot form an obvious regionalized processing effect, resulting in The efficiency of workpiece processing is not high. ③When the flow rate of the machining fluid is too fast, the relative contact time between the too fast abrasive particles and the workpiece is too short, and the processing force is too large, resulting in poor processing effect. This makes controlling the flow rate a hassle.

Contents of the invention

The purpose of the present invention is to solve the problem that the polishing effect of the workpiece is not obvious when using the abrasive flow to polish the surface of the workpiece in the prior art, and proposes a reverse ultrasonic assisted gas-liquid-solid three-phase abrasive flow polishing method and device.

The present invention achieves the above object through the following technical solutions:

The reverse ultrasonic-assisted gas-liquid-solid three-phase abrasive flow polishing processing method is used to apply reverse ultrasonic waves to the gas-liquid-solid three-phase abrasive flow polishing process. At the position where the direction of abrasive grain flow is opposite to that of the gas-liquid-solid three-phase abrasive grain flow and forms an included angle with the direction of the gas-liquid-solid three-phase abrasive grain flow, an The flow direction forms a reverse ultrasonic wave at an included angle. The above-mentioned reverse ultrasonic wave compresses the micro-sized bubbles near the workpiece processing surface in the gas-liquid-solid three-phase abrasive flow medium containing micro-sized bubbles, causing the micro-sized bubbles to collapse, and the micro-sized bubbles When collapsing, a reverse micro-shock wave that is opposite to the direction of the gas-liquid-solid three-phase abrasive flow will be generated. The micro-shock wave will generate a large pressure in the local area of the gas-liquid-solid three-phase abrasive flow, resulting in a microscopic explosion , and through the microscopic explosion, the vertical downward component force will accelerate and push the abrasive particles around the micro-sized bubbles downward, thereby greatly improving the relationship between the gas-liquid-solid three-phase abrasive particle flow and the raised peaks on the workpiece processing surface. Contact probability and force; at the same time, the component force produced by the explosion and the gas-liquid-solid three-phase abrasive flow direction can relatively block the abrasive particles and increase the contact time between the abrasive particles and the workpiece processing surface.

Further, the power and frequency of the reverse ultrasonic wave are artificially controlled through an external circuit and a control system, and then the collapse rate of the micro-sized bubbles in the gas-liquid-solid three-phase abrasive flow can be artificially controlled to improve the processing speed of the micro-sized bubbles close to the workpiece. Collapse chance at the surface. It can further prevent the micro-sized bubbles from collapsing too much or too small force to damage the surface of the workpiece or reduce the processing efficiency, thereby improving the beneficial effect of micro-sized bubbles collapsing on processing.

Reverse ultrasonic-assisted gas-liquid-solid three-phase abrasive flow polishing device, including ultrasonic transducer, flat circular piston emitter, fixed flange, three-phase abrasive flow channel, channel cover plate, and sealing connection plate and the base, the three-phase abrasive flow channel is fixed on the base, the flow channel cover plate is fixed on the three-phase abrasive flow channel, the outlet and the inlet of the three-phase abrasive flow channel are equipped with threaded pipes, and the three-phase There is a groove for installing a polished workpiece in the abrasive flow channel; the ultrasonic transducer is connected to a flat circular piston-type emitter, and the flat circular piston-type emitter is connected to the end of the flow channel cover through a sealed connection plate. One inclined side, the ultrasonic transducer emits ultrasonic waves into the three-phase abrasive flow channel through the plane circular piston-type emitting head, and the flow direction of the gas-liquid-solid three-phase abrasive flow in the three-phase abrasive flow channel It is opposite to the direction of the ultrasonic wave and forms an included angle; the ultrasonic transducer is fixed on the base through a fixed flange.

Further, the fixed flange is fixed on the base through a clamp.

Further, the sealing connection plate and the flow channel cover plate are sealed and connected by an O-ring.

Further, the ultrasonic wave emitted by the ultrasonic transducer through the planar circular piston-type emitter is an elastic mechanical vibration wave with a frequency of 20KHz and a power of 100W. The above-mentioned ultrasonic waves will compress the solids or cavitation bubbles in the process of propagating in the three-phase abrasive flow medium. The cavitation bubbles may collapse during the compression process, and when they collapse, they will produce a three-phase abrasive flow medium. The reverse micro-shock wave with particle flow at a certain angle makes the local area have a large pressure and thus produces a micro-explosion effect.

Further, the three-phase abrasive particle flow is a mixed abrasive particle fluid formed by uniformly mixing liquid-solid two-phase abrasive particle flow and micro-sized bubbles, the micro-sized bubbles are cavitation bubbles with a diameter of 1-100um, and the micro-sized Bubbles are generated by the micro-nano bubble pump and uniformly mixed into the liquid-solid two-phase abrasive flow.

Further, the fixed flange includes a master plate and a sub-plate, a plastic gasket is installed between the sub-plate and the ultrasonic transducer, and a rubber shock-absorbing gasket is installed between the master plate and the ultrasonic transducer. The transmission loss of ultrasonic waves is greatly reduced by plastic gaskets and rubber shock-absorbing washers, thereby ensuring the integrity of the ultrasonic transducer output ultrasonic waves.

The liquid-solid two-phase abrasive flow is a polishing fluid medium uniformly mixed with abrasive grains and water or light oil in a certain proportion. The proportion of abrasive grains is usually 15%, and the abrasive grains are generally silicon carbide or aluminum oxide particles.

The beneficial effects of the present invention are:

1) Apply the effect of reverse ultrasonic wave to promote the collapse of micro-sized bubbles in the fluid medium to produce micro-explosion effect in abrasive flow polishing. The two component forces generated by the effect of micro-explosion effect, the vertical component force is used to improve the abrasive particle size. The contact probability and force of the convex peaks on the workpiece processing surface, and the reverse horizontal component force can form a relative retardation effect on the abrasive particles, increase the interaction time between the abrasive particles and the workpiece, and greatly improve the polishing efficiency of the abrasive flow.

2) The use of reverse ultrasonic waves makes the control of the abrasive particle flow rate in the three-phase abrasive particle flow more precise. By changing the flat rate, power and reverse angle of the ultrasonic waves, the processing effect can be optimized to achieve more precise processing.

3) Using the gas-liquid-solid three-phase abrasive flow to repeatedly polish the surface of the workpiece in the polishing system can improve the utilization efficiency of the gas-liquid-solid three-phase abrasive flow, and can effectively filter processing residues to reduce sewage discharge. Realize clean processing, save energy, and be green and environmentally friendly.

Description of drawings

Fig. 1 is a flow chart of a reverse ultrasonic-assisted gas-liquid-solid three-phase abrasive flow polishing process.

Fig. 2 is a schematic structural view of a reverse ultrasonic-assisted gas-liquid-solid three-phase abrasive flow polishing device.

Fig. 3 is a sectional view of the assembly structure of the reverse ultrasonic transducer horn and the fixed flange.

Fig. 4 is a cross-sectional view of the assembly structure of the three-phase abrasive particle flow channel and the planar circular piston-type emitter.

In the figure, 1-base, 2-threaded pipe, 3-runner cover, 4-workpiece, 5-seal connection plate, 6-plane circular piston emitter, 7-sub-plate, 8-mother plate, 9- -horn, 10-lower pressure block, 11-piezoelectric ceramic element, 12-electrode element, 13-preload screw, 14-upper pressure block, 15-fixture, 16-three-phase abrasive flow channel, 17-Rubber shock-absorbing washers, 18-Plastic spacers. the

Detailed ways

The present invention will be further described below in conjunction with accompanying drawing:

Referring to accompanying drawings 1 to 4, a reverse ultrasonic-assisted gas-liquid-solid three-phase abrasive flow polishing process, the specific technical idea can be described as follows: from the threaded pipe 2 in the polishing processing device to the three-phase abrasive flow channel 16 Inject the gas-liquid-solid three-phase abrasive particle flow in a turbulent state, turn on the ultrasonic transducer at the same time, use the external circuit and control system to adjust the power and frequency of the ultrasonic transducer to emit ultrasonic waves, and take out the workpiece after a certain period of continuous work 4 Carry out measurements and draw conclusions about processing effects. Among them, under the adjustment of the external circuit and the control system, combined with the processing effect obtained from the measurement of the workpiece 4, multiple experiments were carried out to make the ultrasonic wave achieve the best effect of accelerating the micro-sized bubble collapse rate in the three-phase abrasive flow, and finally draw up Experimental processing technology.

The reverse ultrasonic-assisted gas-liquid-solid three-phase abrasive flow polishing processing device involved in the above scheme includes an ultrasonic transducer, a flat circular piston-type emitter 6, a fixed flange, a three-phase abrasive flow channel 16, and a The channel cover plate 3, the sealing connection plate 5 and the base 1, the three-phase abrasive flow channel 16 is fixed on the base 1, the flow channel cover plate 3 is fixed on the three-phase abrasive flow channel 16, and the three-phase abrasive flow channel 16 is fixed on the three-phase abrasive flow channel. Both the outlet and the entrance of the channel 16 are provided with a threaded pipe 2, and the three-phase abrasive flow channel 16 is provided with a groove for installing a polished workpiece 4; the ultrasonic transducer is connected to a plane circular piston-type emitter 6, The planar circular piston-type emitter 6 is connected to an inclined side of the flow channel cover plate 3 through the sealing connection plate 5, and the ultrasonic transducer emits ultrasonic waves into the three-phase abrasive particle flow through the planar circular piston-type emitter 6 In the flow channel 16, the flow direction of the gas-liquid-solid three-phase abrasive flow in the three-phase abrasive flow channel 16 is opposite to the direction of the above-mentioned ultrasonic wave and forms an included angle; the ultrasonic transducer passes through the fixed flange The disc is fixed on the base 1. The fixed flange is fixed on the base 1 by a clamp 15 . The sealing connection plate 5 and the flow channel cover plate 3 are hermetically connected by an O-ring.

The ultrasonic generator includes a horn 9, a lower pressing block 10, a piezoelectric ceramic element 11, an electrode element 12, a preload screw 13 and an upper pressing block 14, and the lower pressing block 10 and the upper pressing block 10 are arranged on piezoelectric The two ends of the ceramic element 11 are fixed by pre-tightening bolts 13, the electrode element is connected to the piezoelectric ceramic element 11, and one end of the lower pressure block 10 is connected to the plane circular piston emitter 6 through the horn 9, and the flange is fixed Be fixed on the horn 9.

The ultrasonic wave emitted by the ultrasonic transducer through the planar circular piston-type emitter 6 is an elastic mechanical vibration wave with a frequency of 20KHz and a power of 100W. The above-mentioned ultrasonic waves will compress the solids or cavitation bubbles in the process of propagating in the three-phase abrasive flow medium. The cavitation bubbles may collapse during the compression process, and when they collapse, they will produce a three-phase abrasive flow medium. The reverse micro-shock wave with particle flow at a certain angle makes the local area have a large pressure and thus produces a micro-explosion effect.

Three-phase abrasive flow is a mixed abrasive fluid formed by uniform mixing of liquid-solid two-phase abrasive flow and micro-sized bubbles. The micro-sized bubbles are cavitation bubbles with a diameter of 1-100um. The nanobubble pump generates and mixes evenly into the liquid-solid two-phase abrasive flow.

The fixed flange includes a master disc 8 and a sub disc 7, a plastic gasket 17 is installed between the sub disc 7 and the ultrasonic transducer, and a rubber damping washer 18 is installed between the master disc 8 and the ultrasonic transducer. The master disc 8 and the sub disc 7 are fixed by bolts.

The above-described embodiments are only preferred embodiments of the present invention, and are not limitations to the technical solutions of the present invention. As long as they are technical solutions that can be realized on the basis of the above-mentioned embodiments without creative work, they should be regarded as falling into the scope of the patent of the present invention. within the scope of protection of rights.

Claims (8)

1. reverse ultrasonic assistant gas-liquid-solid three-phase abrasive Flow polishing processing method, for by reverse ultrasonic applications in gas-liquid-solid three-phase abrasive Flow polishing, it is characterized in that: comprise the steps: ultrasonic generator to be arranged on and gas-liquid-solid three-phase abrasive Flow direction contrary, and with on gas-liquid-solid three-phase abrasive Flow direction shape position in an angle, produce a kind of flow to contrary with gas-liquid-solid three-phase abrasive Flow and with gas-liquid-solid three-phase abrasive Flow direction shape reverse ultrasonic wave in an angle, above-mentioned reverse ultrasonic wave causes micro-dimension bubble to be crumbled and fall to the micro-dimension bubble compression near workpiece machining surface in the gas-liquid-solid three-phase abrasive Flow medium containing micro-dimension bubble, reverse micro laser wave that is a kind of and gas-liquid-solid three-phase abrasive Flow direction contrary can be produced when micro-dimension bubble is crumbled and fall, micro laser wave makes regional area in gas-liquid-solid three-phase abrasive Flow produce very large pressure thus produce micro-explosion effect, and by the component that micro-explosion effect produces vertically downward, impetus is accelerated downwards to the abrasive particle generation around micro-dimension bubble, and then increase substantially contact probability and the active force at described gas-liquid-solid three-phase abrasive Flow and the protruding peak of workpiece machining surface, the component flowing to contrary with gas-liquid-solid three-phase abrasive Flow simultaneously surrounding and watching that detonation produces can play relative retardation effect to abrasive particle, increases the contact action time of abrasive particle and workpiece machining surface.

2. reverse ultrasonic assistant gas-liquid-solid three-phase abrasive Flow polishing processing method according to claim 1, it is characterized in that: described reverse hyperacoustic power and frequency carry out manual control by external circuits and control system, and then can the speed that crumble and fall of micro-dimension bubble in manual control gas-liquid-solid three-phase abrasive Flow, improve the crumble and fall probability of micro-dimension bubble near workpiece machining surface place.

3. reverse ultrasonic assistant gas-liquid-solid three-phase abrasive Flow polishing processing device, it is characterized in that: comprise ultrasonic transducer, planar rondure piston type emitting head (6), fixed flange, three-phase abrasive Flow runner (16), flow passage cover plate (3), be tightly connected dish (5) and base (1), three-phase abrasive Flow runner (16) is fixed on base (1), flow passage cover plate (3) is fixed on three-phase abrasive Flow runner (16), the outlet of three-phase abrasive Flow runner (16) and porch are equipped with screwed pipe (2), the groove of mounting strap polishing workpiece is provided with in three-phase abrasive Flow runner (16), described ultrasonic transducer connects planar rondure piston type emitting head (6), described planar rondure piston type emitting head (6) is by an inclined side of dish (5) the connecting passage cover plate (3) that is tightly connected, ultrasonic wave to be launched by planar rondure piston type emitting head (6) and is entered in three-phase abrasive Flow runner (16) by described ultrasonic transducer, the flow direction of the gas-liquid-solid three-phase abrasive Flow in described three-phase abrasive Flow runner (16) and above-mentioned hyperacoustic direction contrary and be an angle, described ultrasonic transducer is fixed on base (1) by fixed flange.

4. reverse ultrasonic assistant gas-liquid-solid three-phase abrasive Flow polishing processing device according to claim 3, is characterized in that: institute's fixed flange is fixed on base (1) by fixture (15).

5. reverse ultrasonic assistant gas-liquid-solid three-phase abrasive Flow polishing processing device according to claim 3, is characterized in that: described in be tightly connected dish (5) and flow passage cover plate (3) be tightly connected by O RunddichtringO.

6. reverse ultrasonic assistant gas-liquid-solid three-phase abrasive Flow polishing processing device according to claim 3, is characterized in that: described ultrasonic transducer is launched by planar rondure piston type emitting head (6) 'sthe elastic mechanical vibration wave that ultrasonic wave is frequency is 20KHz, power is 100W.

7. reverse ultrasonic assistant gas-liquid-solid three-phase abrasive Flow polishing processing device according to claim 3, it is characterized in that: three-phase abrasive Flow be uniformly mixed to form with micro-dimension bubble by liquid-solid two phase abrasive Flow mix abrasive fluid, the cavitation bubble of described micro-dimension bubble to be diameter be 1 ~ 100um, described micro-dimension bubble is produced by micro-nano airlift pump and Homogeneous phase mixing enters in liquid-solid two phase abrasive Flow.

8. reverse ultrasonic assistant gas-liquid-solid three-phase abrasive Flow polishing processing device according to claim 3, it is characterized in that: described fixed flange comprises stamper (8) and sub-disk (7), plastic spacer (18) is installed between sub-disk (7) and ultrasonic transducer, rubber shock-absorbing packing ring (17) is installed between stamper (8) and ultrasonic transducer.