The powder component accounts for about 60% of the volume fraction share. Raw materials used for injection are grainy. Machine in processing metal raw materials is different from the traditional injection molding machines. The difference is mainly on its plasticizing device. Under the temperature, the binder molten. Thanks to the distribution uniform, boron powder components remain solid in the melt. Not only the loading of the metal powder, particle size and composition of binder affected the processing performance, the uniformity of the mixture also does.
Subsequently, most of the bond component is extracted from the original injection molded parts. So that the so-called brown parts are then passed to make the final sintering furnace. Made of metal and ceramic objects by the PIM applications in many industries, such as medical technology and automotive industry. The mixed raw material depicted in the rheometer, which determines the flow properties. The most common method is the measurement at one point, melt flow index test device. Comparison of the rheological properties of the mixed raw materials uniformity in terms of some of the information. For the same mixture plastic parts of uneven mixture of poor flow properties than the non-bulk material flow properties. Rheological data, however, not only can be used for quality control of raw materials, but also can be used as the input parameters of injection molding simulation program.
Only be added to the heat of the metal powder materials melt when using the traditional capillary rheometer. However, before the actual measurement is no application of shear. The flow of the plasticizing screw should improve the homogenization, usually result in lower viscosity. Or relative effects might be: if the dead time in the plasticizing unit is too long or temperature is too high, then the binder will dissolve, gradually increase the viscosity. This indicates that the data may be obtained by the traditional methods of measurement to describe the real situation. When used to simulate the viscosity data measured directly on the injection molding machine, the new method is more suitable to describe the mold filling process and determine the required pressure and clamping force.
For the tests carried out using the standard formula of the metal powder binder mixture, mixing ratio is changed. The binder content of the stainless steel raw material than the ordinary mixture of 5% higher then the rheological properties of raw materials is shown. The viscosity of the process showed that the content of the adhesive composition is just affect the viscosity value. The raw material can be seen as highly filled systems. These materials are easy to slide in the mold wall. This means that the flow speed of the melt in the mold wall to deviate from the zero value. The rheological machine can quantify this phenomenon.
When the mold temperature increases, the injection pressure must be lower. This reduces the injection integrity. However, the MFQ value is not affected by the state or injection mold parameters. Metal raw material quality remained stable, as long as subjected to the screw torque and barrel temperature. Moreover, when the shear velocity and pressure is not high, it describes the viscosity properties of raw materials. In such conditions, the raw materials are very sensitive to factors affecting the viscosity of the reaction. Similarly, in this case, the metal powder mixed and the amendment of binder plays a role on the mobility.
In metal powder injection molding, uniform mixing of powder particles and binder is essential for quality of injection molded parts. A change of mixture will eventually change fluidity of the melt. Unlike traditional methods, flows tube determines viscosity of the injection molding machine. It forms the desired data. Quality control can monitor the quality of raw materials. The motor electronics read out the screw torque and pass to the machine up to calculate the MFQ value. It describes the heat introduced in plasticizing process.Source:mhcmp
Article Tags: Metal Powder Injection, Powder Injection Molding, Metal Powder, Powder Injection, Injection Molding, Flow Properties