1 Introduction
At present, the domestic and international high-quality stone and jade market is active in development, and the economic development prospects are very broad, thus stimulating and driving the rapid development of related processing industries. In terms of processing difficulty, jade is the most difficult to process. Generally, the Mohs hardness of precious stones such as turquoise is 3 to 4.5, and the Mohs hardness of jade in jade is 4.5 to 5.5, and the hardness of jadeite such as Burmese jade is 6.5 to 7. In layman's terms, the more precious the jade material, the more difficult it is to process. Because in addition to the high hardness, precious jade materials have strict requirements for fine cutting, beautiful cut surface and jade loss.
There are usually two types of technical approaches for the manufacture of cutting saw blades for hard and precious materials such as jade and gemstones:
(1) Process method of powder metallurgy hot pressing and welding: mixing diamond particles with metal powder such as bronze, hot pressing into a cutting wear ring (or block), and then welding the wear ring to the saw blade base. The saw blade used for cutting jade has the fatal weakness of cutting efficiency, large slit, and serious wear of jade.
(2) Electroplated diamond saw blade: After the groove is formed on the outer edge of the saw blade base, the diamond is evenly sprinkled, and then the substrate is bonded to the diamond by electroplating. The saw blade produced by this method can cut all jade materials and work efficiently. However, the following disadvantages exist: 1 diamond particles adhere to the non-edge of the saw blade base during electroplating, so that the thickness of the saw blade is increased, the slit is widened, thereby increasing the loss of jade material; 2 due to the limitation of the plating bath, it is impossible to manufacture large Sized blades of size; 3 electroplating process has serious environmental pollution problems.
This article briefly introduces the technical route developed by our company to process diamond jigs for jade and gemstones.
2 Technical route of the project
In this project, the selected artificial diamond particles are bonded into a piece of flakes by self-developed binder, placed in the edge of the saw blade base with precise design calculation, and the metal edge of the saw blade is made by scientific and reasonable calendering process. Appropriate plastic deformation, which plays a good role in fixing the diamond single crystal. This method of not using electroplating can make large diameter sheets and avoid environmental pollution caused by electroplating.
3 Introduction to development
3.1 Abrasive selection
The dental saw blade developed by this project uses synthetic diamond as the cutting sharp body, and the particle size and concentration of the diamond abrasive should be selected according to the processing technology requirements. Due to the different sizes of saw blades for cutting jade, there are different requirements for the particle size and concentration of diamond. The saw blades produced by our company range in diameter from Φ200 to Φ1250, with a total of 13 bins. We pre-selected 3 particle sizes and 2 concentrations for each size for comparative test screening to determine 13 different sizes of product and diamond grain size.
3.2 Matrix selection and processing
The saw blade base requires both a certain strength and a corresponding toughness and ductility. After the steel grade is selected, the mechanical calculation is performed according to the size of the saw blade, and the thickness is determined to meet the strength required for the application. Another function of the strength requirement is to ensure the cutting efficiency, while the plasticity and toughness provide the metal deformation degree of the saw blade in the pressing pressure delay to firmly support the diamond particle agglomerate to ensure the cutting.
After detailed calculations and tests, high-quality cold-rolled steel sheets imported from Japan were selected as the base material. Its chemical composition is: C<0.08%, Mn=0.30%-0.45%, Al=0.02%-0.07%, and the mechanical properties are “бb=260～350N/mm2, бS<240mm2, δ10≥39%â€. These performance guarantees that the substrate can meet the technical requirements for turning, constitutional and pressure delay.
3.3 Binder trial production
After 10 to 15 types of test comparison, the YJ204 special binder was determined. The binder enables the diamond particles to be flexibly bonded, both to ensure bond strength and to withstand the metal extrusion force of the calendering process. Viewed from the microscope, there is a semi-cured grease bond film between the bonded synthetic diamond agglomerates. When the pressure is not subjected to the rolling stress, the thickness of the adhesive film is large; after the calendering and extrusion, the area of ​​the adhesive film is enlarged, and the thickness is small, but the good particle bonding is always maintained.
3.4 Calendering Process In order to facilitate the calendering operation, we have designed the corresponding moulds suitable for various product sizes. The shape of the mould has a good fit with the shaft holes and side grooves of the saw blade. With the guarantee of the mold, the calendering deformation of the base metal can be concentrated in the alveolar portion. The deformed alveolar is closely combined with the inner diamond-like piece of the diamond to form a convex spherical wave connection, and such a tooth shape is most advantageous for the sawing of the jadeite.
For the selection of calendering process parameters, we carried out hundreds of calendering tests on the basis of mechanical calculations, and accurately measured and recorded the deformation amounts under various pressure intensities. At present, the calendering mechanical parameters selected in the production process have a good correspondence with the diameter of the saw blade.
4 Conclusion
The new patented diamond dental saw blade developed by the company has successfully overcome the shortcomings of the other two types of saw blades for cutting hard materials. Its characteristics are:
(1) The products of this project can cut jade materials, especially jadeite such as jadeite (there are no problems in cutting other hard materials), and the cutting efficiency is high and the guiding property is good.
(2) The dental saw blade is not limited by the electroplating process. The saw blade is large and thin (the thickness of the saw blade with a diameter of 1250mm is only 2.5mm). The slit is thin and the cut surface is beautiful, so that the loss of jade material is small.
(3) Avoid the environmental pollution caused by the electroplating process.
At present, the domestic and international high-quality stone and jade market is active in development, and the economic development prospects are very broad, thus stimulating and driving the rapid development of related processing industries. In terms of processing difficulty, jade is the most difficult to process. Generally, the Mohs hardness of precious stones such as turquoise is 3 to 4.5, and the Mohs hardness of jade in jade is 4.5 to 5.5, and the hardness of jadeite such as Burmese jade is 6.5 to 7. In layman's terms, the more precious the jade material, the more difficult it is to process. Because in addition to the high hardness, precious jade materials have strict requirements for fine cutting, beautiful cut surface and jade loss.
There are usually two types of technical approaches for the manufacture of cutting saw blades for hard and precious materials such as jade and gemstones:
(1) Process method of powder metallurgy hot pressing and welding: mixing diamond particles with metal powder such as bronze, hot pressing into a cutting wear ring (or block), and then welding the wear ring to the saw blade base. The saw blade used for cutting jade has the fatal weakness of cutting efficiency, large slit, and serious wear of jade.
(2) Electroplated diamond saw blade: After the groove is formed on the outer edge of the saw blade base, the diamond is evenly sprinkled, and then the substrate is bonded to the diamond by electroplating. The saw blade produced by this method can cut all jade materials and work efficiently. However, the following disadvantages exist: 1 diamond particles adhere to the non-edge of the saw blade base during electroplating, so that the thickness of the saw blade is increased, the slit is widened, thereby increasing the loss of jade material; 2 due to the limitation of the plating bath, it is impossible to manufacture large Sized blades of size; 3 electroplating process has serious environmental pollution problems.
This article briefly introduces the technical route developed by our company to process diamond jigs for jade and gemstones.
2 Technical route of the project
In this project, the selected artificial diamond particles are bonded into a piece of flakes by self-developed binder, placed in the edge of the saw blade base with precise design calculation, and the metal edge of the saw blade is made by scientific and reasonable calendering process. Appropriate plastic deformation, which plays a good role in fixing the diamond single crystal. This method of not using electroplating can make large diameter sheets and avoid environmental pollution caused by electroplating.
3 Introduction to development
3.1 Abrasive selection
The dental saw blade developed by this project uses synthetic diamond as the cutting sharp body, and the particle size and concentration of the diamond abrasive should be selected according to the processing technology requirements. Due to the different sizes of saw blades for cutting jade, there are different requirements for the particle size and concentration of diamond. The saw blades produced by our company range in diameter from Φ200 to Φ1250, with a total of 13 bins. We pre-selected 3 particle sizes and 2 concentrations for each size for comparative test screening to determine 13 different sizes of product and diamond grain size.
3.2 Matrix selection and processing
The saw blade base requires both a certain strength and a corresponding toughness and ductility. After the steel grade is selected, the mechanical calculation is performed according to the size of the saw blade, and the thickness is determined to meet the strength required for the application. Another function of the strength requirement is to ensure the cutting efficiency, while the plasticity and toughness provide the metal deformation degree of the saw blade in the pressing pressure delay to firmly support the diamond particle agglomerate to ensure the cutting.
After detailed calculations and tests, high-quality cold-rolled steel sheets imported from Japan were selected as the base material. Its chemical composition is: C<0.08%, Mn=0.30%-0.45%, Al=0.02%-0.07%, and the mechanical properties are “бb=260～350N/mm2, бS<240mm2, δ10≥39%â€. These performance guarantees that the substrate can meet the technical requirements for turning, constitutional and pressure delay.
3.3 Binder trial production
After 10 to 15 types of test comparison, the YJ204 special binder was determined. The binder enables the diamond particles to be flexibly bonded, both to ensure bond strength and to withstand the metal extrusion force of the calendering process. Viewed from the microscope, there is a semi-cured grease bond film between the bonded synthetic diamond agglomerates. When the pressure is not subjected to the rolling stress, the thickness of the adhesive film is large; after the calendering and extrusion, the area of ​​the adhesive film is enlarged, and the thickness is small, but the good particle bonding is always maintained.
3.4 Calendering Process In order to facilitate the calendering operation, we have designed the corresponding moulds suitable for various product sizes. The shape of the mould has a good fit with the shaft holes and side grooves of the saw blade. With the guarantee of the mold, the calendering deformation of the base metal can be concentrated in the alveolar portion. The deformed alveolar is closely combined with the inner diamond-like piece of the diamond to form a convex spherical wave connection, and such a tooth shape is most advantageous for the sawing of the jadeite.
For the selection of calendering process parameters, we carried out hundreds of calendering tests on the basis of mechanical calculations, and accurately measured and recorded the deformation amounts under various pressure intensities. At present, the calendering mechanical parameters selected in the production process have a good correspondence with the diameter of the saw blade.
4 Conclusion
The new patented diamond dental saw blade developed by the company has successfully overcome the shortcomings of the other two types of saw blades for cutting hard materials. Its characteristics are:
(1) The products of this project can cut jade materials, especially jadeite such as jadeite (there are no problems in cutting other hard materials), and the cutting efficiency is high and the guiding property is good.
(2) The dental saw blade is not limited by the electroplating process. The saw blade is large and thin (the thickness of the saw blade with a diameter of 1250mm is only 2.5mm). The slit is thin and the cut surface is beautiful, so that the loss of jade material is small.
(3) Avoid the environmental pollution caused by the electroplating process.
Leather Storage Cabinet,Leather Dresser Storage Tower,Drawer Storage Tower Chest,Stackable Drawer Storage Tower
Changzhou Offistyle Furniture Co., Ltd. , https://www.offistylefurniture.com