JPS6154908A - Method of processing ceramics - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a method for processing ceramics.

[Conventional technology and its problems]

What is generally called ceramics includes oxides,
Single-phase ceramics mainly composed of one type of compound such as nitride, carbide, boride, silicide, fluoride, sulfide, selenide, terelide, etc., compounds of two or more of the above ceramics It is made by molding and high-temperature firing of composite ceramics consisting of natural or artificial powdered compounds such as oxides, carbides, or boride-based cermets, which are made by adding metals to the above ceramics. Polycrystalline solid materials made of inorganic compounds
. h; (D'4"'y i, y') 7. (Dj.56
2. - Uni has a higher melting point than metal, has a higher free energy of formation (bonding energy), is extremely chemically stable, and has high hardness, so in order to process it mechanically, The only option is to use ultra-hard tools such as cutting tools and drills that have cutting chips or abrasive grains such as diamond or CBN (cubic boron nitride) as cutting edges, or grinding wheels, and in that case, the cutting or grinding performance is comparable to that of metal. , is significantly lower than that of alloys, and is brittle and easily cracked, so it cannot be processed by mechanical cutting or grinding.

In addition, this type of ceramic is generally referred to as an insulator, and its electrical conductivity is significantly lower than that of metals and alloys, and its thermal conductivity is also extremely low, so it cannot be used with diamond chips or abrasives. The energy required for cutting or grinding using a tool with grains is transmitted to the tool side more than when machining materials such as metals and alloys. It is often significantly larger than the actual case.

As described above, ceramics have a high melting point, high hardness, but break easily, low electrical conductivity, and are chemically stable, making them extremely difficult to process using conventional processing methods. It is known to be a material.

[Problems that the invention attempts to resolve]

Chemically stable compounds such as metal oxides used in ceramics generally have superior acid and alkali resistance compared to ordinary metals and alloys; It is a relatively low temperature region of about
In high temperature ranges, metals and metals.

It has high reactivity as much as gold. That is, as is generally known, ordinary metal oxides are difficult to react with acids (e.g., strong acids such as sulfuric acid), alkalis (e.g., Dissolves in strong alkalis (such as sodium hydroxide).

However, even if a chemical reaction using high-temperature acids, alkalis, etc. as described above is carried out on ceramics, there is a need for containers, supplies, etc. that can withstand such high-temperature acids, alkalis, etc.
There are no reliable materials or means for recovery, etc. (Also, it was difficult in the prior art to cause this chemical reaction to act only on desired local portions of the ceramic workpiece.

[Means for solving problems]

If it were possible to apply the reaction effect of such high-temperature acids and alkalis locally to the desired processed part of the ceramic, to separate it from other surrounding parts, and then to remove that processed part by some means. , it becomes possible to process ceramics.

Such processing is not limited to high-temperature acids and alkalis; for example, electrolytic solutions of neutral salts such as NaCl, which generate acid at the positive electrode and alkali at the negative electrode, chemically active ions, such as halogen ions, etc. It may also be an embodiment in which the oxide in the part concerned is decomposed by acting on the ceramic under predetermined high temperature conditions.

The present invention has been made based on the above-mentioned viewpoint, and involves injecting a desired unit amount of a processing fluid in which an electrolyte such as acid or alkali is dissolved in water onto a unit local area of the surface area of a desired processing portion of a ceramic workpiece. Electrical energy is supplied to the local area by flowing, dripping, etc., causing electric discharge and a high temperature state, and further producing an electrolytic action, causing acid or alkali, etc. to be applied to the local area. Preferably, all or most of the acid or alkali in the supplied machining fluid reacts with the ceramics in the high temperature state of the machining fluid,
Processing is performed by mechanically removing altered products or residues from this reaction, or reaction parts weakened by the reaction, from the local area using an ultrasonic vibration processing tool to which ultrasonic vibration energy is applied. Then, the desired target processing is performed by sequentially controlling and moving the processing local area to a predetermined position on the ceramic workpiece in a horizontal plane or in the thickness direction.

In addition, the present invention can be applied to conventional electrical machining, ultrasonic machining,
Rather than simple processing in which each processing method such as chemical processing is applied individually, the above processing methods are not limited to the characteristics and characteristics of each processing method (i.e., the timing of processing, for example, for the same part of the workpiece). Processing using one processing method, such as applying another processing method almost simultaneously or immediately after applying one processing method, or applying two or more processing methods alternately. This method overcomes the difficulties in processing ceramics by using a composite processing method that allows other processing methods to be used as long as the action or effect remains.

[Effect]

With the above configuration, high-temperature acid or alkali machining fluids can be collected and removed from the machining section, even if there is a sufficient amount to be collected, if cooling fluid is not required for ultrasonic machining. , the amount can be extremely small, and
Since there is almost no possibility that the recovered machining fluid is in a high temperature state, it is possible to construct a machining apparatus that achieves the object of the present invention.

In the present invention, electrolytic discharge energy (accompanied by combined effects such as electrochemical action due to electrolysis, energization heating action due to electricity supply, and heat and impact action due to discharge) is used as the energy supplied to the desired machining part, For example, convert this to number 10
Since the heat is applied to a predetermined local range of μm to 1 μm and no heat is applied to other areas, local processing becomes possible.

Further, since the ceramic material to be processed has poor thermal conductivity and relatively little heat diffusion from the local part of the workpiece, the reaction with the acid, alkali, etc. heated to high temperature in the present invention takes place locally.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

The drawing is an explanatory diagram showing one embodiment of a processing device used when carrying out the method of the present invention.

In the figure, 1 is the machining fluid supply nozzle, 2 is the machining fluid supply nozzle 1
one electrode provided at the tip of the arm, 4 the other electrode attached to the arm 3, 5 an ultrasonic transducer, 6
is a horn attached to one end of the ultrasonic vibrator 5; 7 is a horn; an ultrasonic processing tool attached to the tip of 6;
8 is a workpiece.

The machining fluid supply nozzle 1 has a wide and flat end spout, and one electrode 2 (son) is provided here, and the other electrode 4 (minus) extends forward from the nozzle 1. It is provided at the tip of the extended arm 3 so as to be in contact with the machining fluid ejected from the nozzle 1.

The ultrasonic vibrator 5 is attached to the arm (not shown) of the ultrasonic processing machine and converts high frequency current into mechanical vibration, and the horn 6 provided at one end of the ultrasonic vibrator 5 converts the amplitude of this vibration. It is enlarged and transmitted to the tool 7 attached to the tip.

The workpiece 8 is attached to a cross slide table (not shown) and is configured to be moved to any position on a horizontal plane under servo control.

Then, from the machining liquid supply nozzle 1, for example, a concentration of 5 to .
40% salt M (HCI) at a speed of about lQm/s ~ 100
m/s and a flow rate of approximately 1 to 1 Qcc in a film form according to the processing area by the ultrasonic processing tool 7, and one electrode 2 (child seed) provided in the nozzle 1 is attached to this processing liquid.
A voltage of direct current, alternating current, high frequency, or intermittent voltage pulses is applied between the other electrode 4 (-electrode), and the machining fluid is heated to a predetermined high temperature state by energization, electrolysis, and discharge. The material is supplied to the surface of the ceramic to be processed on the workpiece 8 to cause decomposition of the ceramic, a reaction layer, and an embrittlement layer 8a, and at the same time, the workpiece 8 is sequentially controlled and moved in the direction of the arrow in the figure to form this layer 8a. Lightly contact the ultrasonic machining tool 7 to apply ultrasonic vibration energy, thereby causing ultrasonic vibration a.
Remove by cutting.

If necessary, abrasive grains mixed and dispersed in light oil or the like may be supplied between the ultrasonic machining tool 7 and the workpiece 8 by an appropriate means according to the conventional means of ultrasonic machining. You may let them.

Further, the electrolyte in the machining fluid supplied from the machining fluid supply nozzle 1 does not necessarily have to be a strong acid or a strong alkali, and may be a neutral salt such as sodium chloride or potassium chloride. A similar effect can be obtained by generating acid at the positive electrode and alkali at the negative electrode.

〔Effect of the invention〕

According to the present invention, a machining fluid such as an acid or alkali is heated to a high temperature by applying and energizing electric energy, and is further electrolyzed to be locally supplied onto the ceramic workpiece, whereby the workpiece ceramic A special composite machining method in which at least a portion of the material undergoes a reaction such as decomposition, melting, etc., weakens the part, and then mechanically removes that part using an ultrasonic machining tool that is applied with ultrasonic vibration energy. By applying this, drilling, engraving, and
Processing such as cutting, forming of grooves, etc. is possible, and it is possible to easily and inexpensively provide ceramic products that are expected to be applied in a wide range of areas.

If the machining fluid is supplied in an amount larger than the surface, the workpiece stage is used as one electrode and the ultrasonic machining tool is used as the other electrode. Since the object of the present invention can be achieved by generating a minute 1jk electric current around the proximal tip of the workpiece, the electrodes 2, 4, etc. are not essential components of the present invention.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing one embodiment of a processing device used when carrying out the method of the present invention.

Claims (6)

[Claims] (1) Supplying a processing liquid in which an electrolyte is dissolved in water to the surface area of the desired processing part of the ceramic workpiece. Electrical energy is applied to the surface area of the processing part in a state in which it is interposed by immersion, etc., and the above processing is performed. 1. A method for processing ceramics, which comprises altering a portion of the ceramic, and then subjecting the altered portion to ultrasonic processing using an ultrasonic vibration processing tool that applies ultrasonic vibration energy to the altered portion. (2) The method for processing ceramics according to claim 1, wherein the electrolyte is a strong acid. (3) The method for processing ceramics according to claim 1, wherein the electrolyte is a strong base. (4) The method for processing ceramics according to claim 1, wherein the electrolyte is a salt. (5) The method for processing ceramics according to any one of claims 1 to 4, wherein the electric energy applied to the surface area of the processing part is a current passed through the processing fluid. (6) Claims 1 to 4, wherein the electrical energy applied to the surface area of the processed part is energy provided by electric discharge between a pair of electrodes provided close to the surface of the processed part. How to process ceramics.