TWI550141B - Electrochemical Polishing of Magnesium Metal Components - Google Patents

Description

Electrochemical polishing method for magnesium metal members

The present invention relates to an electrochemical polishing method, and more particularly to an electrochemical polishing method for a magnesium metal member.

Magnesium metal components have been widely used in transportation, electronic products and implants in recent years due to their light weight, high specific strength, good heat dissipation, good electromagnetic shielding, good impact resistance and good recovery. In the field of sexual medical equipment. In order to ensure that the magnesium metal component can have a good quality and a finished surface, it is necessary to perform metallographic analysis and surface finishing treatment on the magnesium metal component, and in the case of metallographic analysis and surface finishing treatment, it is required The metallographic test pieces and the rough processed products of the magnesium metal members were respectively mechanically polished to obtain clear metallographic photographs and finished surfaces, respectively.

However, general mechanical polishing is achieved in an artificial manner, and in addition to being time consuming and labor intensive, it is often impossible to make a magnesium metal member have a uniform finishing surface due to a human error. Moreover, the mechanical polishing method is difficult to apply to delicate and fine magnesium metal members. For example, medically used magnesium alloy blood vessel stents are not only small in size but also have a relatively complicated shape, and therefore cannot be mechanically polished. The way to achieve the purpose of surface finishing.

In view of the above disadvantages of the prior art, the object of the present invention is It saves time and labor required for polishing magnesium metal parts, and polishes fine magnesium metal parts.

In order to achieve the foregoing object, the technical means adopted by the present invention is to provide an electrochemical polishing method for a magnesium metal member, the method comprising: placing an anode and a cathode in an organomagnesium electrolyte, the anode being a a magnesium metal member; and applying an electrolytic voltage between the anode and the cathode to obtain a polished magnesium metal member; wherein the organomagnesium electrolyte comprises a solvent and an organomagnesium electrolyte, the solvent being selected from The following group is composed of: ethyl ether, tetrahydrofuran, 2-methyltetrahydrofuran, and cyclopentyl methyl ether, and the organomagnesium electrolyte is selected from the following Group consisting of: methyl magnesium chloride, ethyl magnesium chloride, phenyl magnesium chloride, alkoxy magnesium bromide, and alkoxymagnesium chloride (alkoxy magnesium chloride).

Preferably, the organomagnesium electrolyte in the organomagnesium electrolyte has a molar number of between 1.0 moles and 2.0 moles per 1 liter (L) of the organomagnesium electrolyte.

Preferably, the organomagnesium electrolyte contains a supporting electrolyte, and the supporting electrolyte is aluminum chloride.

More preferably, the molar amount of the supporting electrolyte in the 1 L organomagnesium electrolyte is between 0.05 mole and 0.15 mole.

Preferably, the magnesium metal member contains 90.00 weight percent (wt%) or more of magnesium based on the entirety of the magnesium metal member.

More preferably, the magnesium metal member contains 90.00 wt% to 99.00 wt% of magnesium based on the entirety of the magnesium metal member.

The cathode is stainless steel, an aluminum member containing 99.90% by weight or more of aluminum, or a tin member containing 99.90% by weight or more of tin.

Preferably, the magnesium metal member as an anode and the cathode are placed in the organomagnesium electrolyte, and the electrolytic voltage is applied between the magnesium metal member as the anode and the cathode to obtain The step of polishing the magnesium metal member further includes the step of covering an inert gas on the surface of the organomagnesium electrolyte.

Preferably, the step of applying the electrolysis voltage between the anode and the cathode to obtain the polished magnesium metal component comprises: applying the normal pressure and an operating temperature of 30 ° C to 40 ° C Electrolytic voltage and current density of 25 mA/cm 2 (mA/cm ² ) to 50 mA/cm ² [by adjusting the electrolysis voltage to an electrolysis voltage of 3 volts (V) to 10 V] between the anode and the cathode And the step of obtaining the polished magnesium metal member and a reduced magnesium metal.

In the method of producing magnesium metal, the atmospheric pressure is 1 atm.

Based on the above, the electrochemical polishing method of the magnesium metal member is to polish the magnesium metal member by electrochemical polishing, which can simultaneously achieve the time and labor required for manual polishing, and fine The advantage of polishing magnesium metal components.

10, 10A‧‧‧Metal metal components

20, 20A‧‧‧ cathode

21, 21A‧‧‧ first cathode parts

22, 22A‧‧‧second cathode parts

30‧‧‧Organic electrolyte

S1, S2, S3‧‧‧ steps

1 is a flow chart of a method for electrochemical polishing of a magnesium metal member of the present invention; and FIG. 2 is a schematic view showing a configuration of an anode, a cathode and an electrolyte of an electrochemical polishing method for a magnesium metal member according to Embodiment 1 of the present invention; The schematic diagram of the arrangement of the anode, the cathode and the electrolyte of the electrochemical polishing method for the magnesium metal member according to the second embodiment of the present invention; and FIG. 4 is a magnesium alloy for the electrochemical polishing method of the magnesium metal member according to the second embodiment of the present invention. Schematic diagram of the stereoscopic appearance of a metal member (anode).

In the following, embodiments of the present invention will be described in detail by the following specific embodiments, and those skilled in the art can readily understand the advantages and functions of the present invention, and without departing from the invention. Various modifications and changes are made in the spirit of the invention to practice or apply the invention.

Example 1

1 and 2, the electrochemical polishing method of the magnesium metal member of the present embodiment is as follows. In the present embodiment, the magnesium metal member 10 used was a metallographic test piece containing 98% by weight of magnesium.

First, as described in step S1, the magnesium metal member 10 is used as an anode, and the magnesium metal member 10 and a cathode 20 are placed in an organic electrolyte 30. In this embodiment, the cathode 20 is stainless steel; the organomagnesium electrolyte 30 comprises a solvent, an organic electrolyte and a supporting electrolyte, the solvent is 1 L of tetrahydrofuran, and the organic electrolyte is B. The magnesium chloride, the supporting electrolyte is aluminum chloride; wherein, in the 1 L organic magnesium electrolyte 30, the molar amount of the organomagnesium electrolyte in the organic electrolyte 30 is 1.5 mole and the molar concentration of the supporting electrolyte is 0.1 Further, the cathode 20 includes a first cathode member 21 and a second cathode member 22 electrically connected to the first cathode member 21. The first cathode member 21 and the second cathode member 22 are respectively located. Both sides of the magnesium metal member 10.

Next, an inert gas is applied to the surface of the organomagnesium electrolyte 30 as described in step S2; in the present embodiment, the inert gas is nitrogen. The nitrogen gas is a shielding gas to prevent the organomagnesium electrolyte from being decomposed by exposure to air.

Thereafter, as described in step S3, adjusting the electrolysis voltage of a power supply to between 3V and 10V at normal temperature and an operating temperature of 30 ° C, so that the power supply supplies a current density of 25 mA/cm ² to the anode. A 90 minute period from the cathode 20, a polished magnesium metal member 10 and a reduced metallic magnesium are obtained, wherein the reduced metallic magnesium is located on the surface of the cathode 20.

In the electrochemical polishing method of the magnesium metal member of the present embodiment, when an electrolytic voltage is applied between the anode and the cathode 20, the protruding portion of the surface of the magnesium metal member 10 as the anode is first oxidized and Dissolved in the organic electrolyte 30, the protruding portion of the surface of the metallographic test piece is removed, thereby obtaining a magnesium metal member 10 having a flat surface, that is, the polished magnesium metal member 10. Wherein, when the protruding portion of the surface of the magnesium metal member 10 is oxidized and dissolved, magnesium ions (Mg ²⁺ ) are released into the organic electrolyte 30, and the magnesium ions move toward the cathode 20, and The surface of the cathode 20 forms a reduced magnesium metal which can be recovered for further use.

In the present embodiment, the polishing of the magnesium metal member 10 is performed electrochemically, and the magnesium metal member 10 is uniformly finished in addition to the time and labor required for manual polishing. surface.

Example 2

The electrochemical polishing method of the magnesium metal member of the present embodiment is the same as the electrochemical polishing method of the magnesium metal member of the first embodiment. The difference between this embodiment and Embodiment 1 is as follows.

Referring to the figure, in the embodiment, the magnesium metal component 10A is a blood vessel stent, and the blood vessel stent is a cylinder having a mesh cylinder wall, and the blood vessel stent is used as an anode, and the cathode 20A is The first cathode member 21A is disposed inside the magnesium metal member 10A, and the second cathode member 22A of the cathode 20A is sleeved on the outer side of the blood vessel holder. The magnesium metal member 10A is made of a magnesium-tin alloy having a magnesium content of 95% by weight and a tin content of the magnesium-tin alloy of 5% by weight based on the entire magnesium-tin alloy.

In the present embodiment, the magnesium metal member 10A is a cylinder having a mesh cylinder wall, and its shape is rather complicated and fine. In this embodiment, the magnesium metal member 10A is electrochemically polished, and the magnesium metal member 10A having a complicated and fine shape can be polished in addition to the time and labor required for manual polishing. And the magnesium metal member 10A having a complicated and fine shape has a uniform surface.

Based on the above, the present invention can polish the metal member by electrochemical polishing, thereby eliminating the need for manual polishing. The time and labor required, the use of complex and finely shaped magnesium metal components and the advantages of recycled magnesium metal.

S1, S2, S3‧‧‧ steps

Claims (4)

An electrochemical polishing method for a magnesium metal member, comprising the steps of: placing an anode and a cathode in an organomagnesium electrolyte, the anode being a magnesium metal member; and at atmospheric pressure and 30 ° C to 40 Applying an electrolytic voltage and a current density of 25 mA/cm ² to 50 mA/cm ² between the anode and the cathode at a working temperature of ° C to obtain a polished magnesium metal member and a reduced magnesium metal; Wherein, the organomagnesium electrolyte comprises a solvent, an organomagnesium electrolyte and a supporting electrolyte, the solvent is 2-methyltetrahydrofuran, and the organomagnesium electrolyte is alkoxymagnesium bromide or alkoxymagnesium chloride, in 1 L. In the organomagnesium electrolyte, the molar amount of the organomagnesium electrolyte in the organomagnesium electrolyte is between 1.0 mol and 2.0 mol, and the molar amount of the supporting electrolyte in the organomagnesium electrolyte is between 0.05 mol and 0.15 mol. between. The method of electrochemical polishing of a magnesium metal member according to claim 1, wherein the magnesium metal member contains 90.00% by weight or more of magnesium based on the entirety of the magnesium metal member. The method of electrochemical polishing of a magnesium metal member according to claim 2, wherein the cathode is stainless steel, an aluminum member containing 99.90% by weight or more of aluminum, or a tin member containing 99.90% by weight or more of tin. The method of electrochemical polishing of a magnesium metal member according to any one of claims 1 to 3, wherein a step of placing the anode and the cathode in the organomagnesium electrolyte and applying the electrolysis voltage to the anode Between the steps of obtaining the polished magnesium metal member with the cathode: A step of covering an inert gas to the surface of the organomagnesium electrolyte.