MICROBIAL DRESSING METHOD FOR SUPER ABRASIVE TOOLS

Abstract

A microbial dressing method for super abrasive tools includes a kind of microbe which is capable of consuming the bond in a certain manner is selected to perform the microbial dressing. Specifically, the microbe is inoculated and cultured in the culture medium to a certain concentration, then the dressing area of the abrasive tool is immersed into the culture liquid to remove the bond in the surface by the action of the microbe, and the control of the dressing amount is realized by controlling the microbe concentration and the soaking time. Precise dressing for super abrasive products, particularly for fine grained abrasive tools can be realized using the present method.

Claims

1. A microbial dressing method for super abrasive tools forming by combination of a super abrasive and a bond, the method comprising the steps of: 1) selecting a microbe depending on the type of the bond, wherein the microbe is capable of consuming the bond in a certain manner; 2) culturing the selected microbe to obtain a microbial culture liquid with an appropriate cell concentration; 3) immersing the dressing surface of the super abrasive tool into the microbial culture liquid to remove the bond of the dressing surface by the action of the microbe; 4) determining the soaking time according to the required removal amount and the removal rate of bond material by the microbial culture liquid, observing the surface topography after the soaking time and judging whether to continue soaking until the requirement is reached, then taking out and cleaning the super abrasive tool.

2. The microbial dressing method for super abrasive products according to claim 1, wherein the removal of the bond is realized through a circulation that the metabolite of the microbe reacts with the bond material to consume the bond and produce a metabolic raw material and the metabolic raw material is reused by the microbe into the metabolite.

3. The microbial dressing method for super abrasive products according to claim 2, wherein the reaction of the metabolite with the bond is oxidation-reduction reaction.

4. The microbial dressing method for super abrasive products according to claim 3, wherein the microbe is Acidithiobacillus ferrooxidans, the metabolic raw material is Fe.sup.2+ ion, the metabolite is Fe.sup.3+ ion, and the bond is a metal-based bond which is capable of reducing Fe.sup.3+ ion to Fe.sup.2+ ion.

5. The microbial dressing method for super abrasive tools according to claim 4, wherein the bond is at least one kind of metal-based bond selected from the group consisting of copper-based, lead-based, zinc-based, cobalt-based, tin-based, chromium-based, cadmium-based, manganese-based, iron-based, nickel-based and aluminum-based bond.

6. The microbial dressing method for super abrasive tools according to claim 4, wherein in step 2, the Acidithiobacillus ferrooxidans is cultured in the culture medium until the concentration of Fe.sup.3+ ion of the metabolite ranges from 6 g/L to 9 g/L to obtain the microbial culture liquid with the appropriate microbial concentration.

7. The microbial dressing method for super abrasive tools according to claim 4, wherein in step 3, the temperature of the microbial culture liquid is maintained at a range from 25° C. to 45° C.

8. The microbial dressing method for super abrasive tools according to claim 1, wherein the microbe is Thiobacillus thiooxidans, Acidithiobacillus ferrooxidans, Acidithiobacillus caldus or Leptospirillum ferrooxidans.

9. The microbial dressing method for super abrasive tools according to claim 1, wherein the super abrasive tool is rotated in the microbial culture liquid to immerse the dressing surface into the microbial culture liquid.

10. The microbial dressing method for super abrasive tools according to claim 2, wherein the microbe is Thiobacillus thiooxidans, Acidithiobacillus ferrooxidans, Acidithiobacillus caldus or Leptospirillum ferrooxidans.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0026] FIG. 1 illustrates structural representation of embodiment 1.

[0027] FIG. 2 illustrates structural representation of embodiment 2.

DETAILED DESCRIPTION OF THE EMBODIMENTS

[0028] A microbial dressing method for super abrasive tools forming by combination of a super abrasive and a bond comprises the following steps:

[0029] 1. selecting a microbe depending on the type of the bond, wherein the microbe is capable of consuming the bond in a certain manner;

[0030] 2. selecting a particular culture medium, controlling appropriate environment conditions such as temperature, humidity and pH, and culturing the selected microbe to obtain a microbial culture liquid with an appropriate cell concentration;

[0031] 3 immersing part or all of the super abrasive tool into the microbial culture liquid, or making the super abrasive tool move at a low speed according to the requirement of the dressing surface;

[0032] 4. determining the soaking time according to the required removal amount and the removal rate of the bond material by microbial culture liquid, observing the surface topography after the soaking time and determining whether to stop soaking;

[0033] 5. judging whether-it meet the requirement, soaking until the requirement is reached and then taking out and cleaning the super abrasive tool.

[0034] Specifically, the removal of the bond is realized in a way that the metabolite of the microbe reacts with the bond material to consume the bond and produce a metabolic raw material and the metabolic raw material is reused by the microbe to change into the metabolite. The microbe is Acidithiobacillus ferrooxidans, Thiobacillus thiooxidans, Acidithiobacillus caldus, Leptospirillum ferrooxidans, etc.

[0035] In a preferred embodiment, the reaction of the metabolite with the bond is oxidation-reduction reaction, and the solid-state bond is transformed to soluble product dissolving in the culture liquid through the reaction, thereby to achieve the removal of the bond.

[0036] In the following, the Acidithiobacillus ferrooxidans is used as an example of specific description.

Embodiment 1

[0037] Referring to FIG. 1, grinding tool 1 of this embodiment is an iron-based bonded diamond grinding wheel with diamond abrasive grains in a size of about 20 μm. The selected microbe is acidithiobacillus ferrooxidans. The dressing method is performed as follows:

[0038] a. A container 3 contains a volume of acidithiobacillus ferrooxidans culture liquid 2 which is mainly composed of acidithiobacillus ferrooxidans 4, culture medium and cell metabolites such as Fe.sup.3+ ion. Acidihiobacillus ferrooxidans culture liquid 2 is obtained through inoculating and culturing in sterile culture medium. The culture medium is 9K medium and sterilized under high temperature, and then Acidithiobacillus ferrooxidans 4 is inoculated to the culture medium and cultured in a constant temperature shaker. Acidihiobacillus ferrooxidans 4 obtains sufficient nutrients and chemical energy from the culture medium to undertake cell division and proliferation. After the lag phase, the exponential growth phase, the plateau phase, the concentration of bacteria increases, light green Fe.sup.2+ ions in the medium are continuously transformed into yellow Fe.sup.3+ ions by Acidithiobacillus ferrooxidans 4 and the color of the culture liquid changes to yellow brown. The culture is stopped after the concentration of Fe.sup.3+ ions reaches 8 g/L.

[0039] b. Container 3 is placed on the dresser table, the grinding machine is started to drive grinding tool 1 rotate at a low speed. The grinding area of grinding tool 1 is immersed in microbial culture liquid 2 and kept rotating. The temperature of Acidithiobacillus ferrooxidans culture liquid 2 is kept at a range from 30° C. to 40° C. Fe.sup.2+ ions are changed to Fe.sup.3+ ions continuously by series of self-biochemical reactions of Acidithiobacillus ferrooxidans 4. Fe.sup.3+ ions are capable of reacting chemically with the iron-based bond because of the oxidability, and thereby the iron-based bond of zero-valence state is oxidized to Fe.sup.2+ ions which are capable of dissolving into the culture liquid, meanwhile Fe.sup.3+ ions are reduced to Fe.sup.2+ ions. Fe.sup.3+ ions are consumed continuously and reused by Acidithiobacillus ferrooxidans 4 to generate Fe.sup.3+ ions, which forms a cycle process to realize the removal of the bond by the microbial culture liquid.

[0040] c. According to the abrasive grain size of grinding tool 1, the type of the bond and the removal rate of the bond material by the microbial culture liquid to the bond, the time of the iron-based grinding wheel soaking in the Acidithiobacillus ferrooxidans culture liquid 2 is calculated for about 36 minutes. The grinding area of the grinding wheel is maintained in the microbial culture liquid until the calculated soaking time is reached, then the surface topography is detected and the exposure height of the abrasive and the chip space between the abrasive is observed.

[0041] d. If the observation results do not meet the requirement, the dressing process is to be continued. If the observation results meet the requirement indicating that the removal amount of the bond is enough, then take out grinding tool 1 from the culture liquid and remove container 4, the dressing process is finished.

Embodiment 2

[0042] Referring to FIG. 2, grinding tool of this embodiment is a copper-based bonded diamond abrasive disk 6 with diamond abrasive grains in a size of about 10 μm. The selected microbe is Acidithiobacillus ferrooxidans.

[0043] The dressing method is similar to embodiment 1. Abrasive disk 6 is rotated at a low speed to immerse all the grinding area of abrasive disk 6 into Acidithiobacillus ferrooxidans culture liquid 2. Fe.sup.3+ ions react chemically with the copper-based bond, and thereby copper-based bond of zero-valence state is oxidized to Cu.sup.2+ ions which are capable of dissolving into the culture liquid to realize the removal of the copper-based bond. The time of abrasive disk 6 to be soaked in Acidithiobacillus ferrooxidans culture liquid 2 is calculated for about 15 minutes to achieve a certain removal amount of the bond, and then the dressing is finished.

[0044] Although the present invention has been described with reference to the preferred embodiments thereof for carrying out the patent for invention, it is apparent to those skilled in the art that a variety of modifications and changes may be made without departing from the scope of the patent for invention which is intended to be defined by the appended claims.