时间:2021-08-21
The production and manufacture of aluminum alloy straight grinding heads include three key whole processes of mixture preparation, forming, and calcination. In order to make the aluminum alloy have the necessary compressive strength and strength, the bonding metal material is added to the cementite in fine powder form, and other components are added when necessary. These types of raw materials are milled by a ball mill or rod mill for a certain period of time to make a homogeneous mixture with a certain specified particle size distribution. Milling is generally carried out in aqueous solutions of organic chemicals such as ethanol and hexane. In addition to the compound used for pressing, a forming agent (such as paraffin) must be added to the compound. The slurry obtained by grinding can be used in different drying methods (such as spray dryer) to better remove organic chemical liquids.
Cold extrusion is the most common forming method. It is the whole process of processing the mixed material into a compact with a certain relative density, compressive strength, appearance and specifications. The abrasive tools are used to make the final product look, and the specifications of the calcination are fully considered. Therefore, the specifications of the abrasive tools should exceed the specifications of the final product. It is important to ensure the uniformity of the density of each position of the compact, without layers, cracks, and uncompressed conditions, which is technically important to inhibit forming. Manufacturing often chooses dual suppression or multi-directional suppression.
In terms of relative cold extrusion, another forming method is pressing. It is to pack the mixed material into a high-purity graphite mold in powder form, and inhibit the forming at the calcination temperature. This type of method is generally used for large and medium-sized or some unique products. Another way to produce large and medium-sized and special-shaped products is isostatic pressing. Put the powder into a closed soft mold, and then put it into the liquid in a closed high-pressure container. Make the working pressure in the liquid rise according to the soft mold cover to moderately suppress the powder form. Because the working pressure on the powder form is the same in each direction, the relative density of each position of the compact is even. Thermosetting plastic soft plastic epoxy resin is the key raw material for making soft molds at this stage. The composition of the tackifier can be adjusted according to the composition to be integrated into the manufacture of abrasive tools for different main purposes.
Extrusion molding is suitable for the production of long and complex cross-section products, such as tubes, rods and strips of carbide tools. The tackifier causes a critical hazard to the entire process of extrusion molding, and its characteristic is that it is added in a large amount and requires excellent bonding. Tackifiers are generally composed of organic solvents, organic chemical binders and surfactants. Mixing the tackifier evenly into the mixture is a key step in the quality management of extrusion molding. In the whole process of extrusion, in order to have sufficient exhaust pipe, it is carried out in a press equipped with vacuum equipment. The working pressure of extrusion molding lies in the characteristics of the plasticized powder. Extrusion molding is not good, usually leading to cracks, poor relative density and other shortcomings, should attach great importance to the quality of the extrusion molding blank.
The calcination of the stone carving alloy grinding head is high performance liquid phase calcination, which is carried out under the standard that the binder phase is high performance liquid phase. The compact is heated to 1350℃~2200℃ in a vacuum sintering furnace. The linear shrinkage rate of the compact during calcination is about 12%, and the volume shrinks around 80%. The value of the shrinkage depends on the particle size distribution of the powder and the composition of the aluminum alloy.
The calcination of tungsten steel sand grinding head is a complicated whole process of physics. This whole process includes the whole process of tackifier resin adsorption, degassing, solid phase calcination, high performance liquid phase calcination, grain refinement strengthening, high density, melting and dissolving. The compact produces products with certain composition, organizational structure, characteristics and specifications under special calcination standards. This kind of processing technology standard differs greatly depending on different calcining equipment.