How to prolong the life of Customized 230v dc motor?
Some people also do a lot of work to improve the surface hardness and wear resistance of the commutator(sliding ring). For example, high hardness alloy materials are used instead of pure copper or silver copper alloys. However, no alloy material at room temperature can have electrical conductivity compared to pure copper, including silver copper alloys. Almost all metals, as the content of their alloy elements increases, the conductivity will deteriorate sharply. The commutator(sliding ring) has undoubtedly become an electric heater, which is extremely harmful to the entire machine.
In another method, the surface hardening of the commutator(sliding ring) is performed, such as cold hardening or plating a layer of high hardness film on the surface of the commutator(sliding ring), but the effect is not satisfactory. First of all, the role of cold hardening is very limited. Under the conditions of high-speed operating friction, the temperature on the surface of the commutator(sliding ring) will rapidly rise and stabilize at a higher level, which will make the grain distortion and lattice distortion caused by cold hardening, which will soon be eliminated due to recrystallization., This causes the surface hardness to return to its original state. The surface plating coating must be a conductor. As mentioned above, because the coating is hard, its conductivity must be far inferior to that of the commutator(sliding ring) body metal. Due to the significant potential differences, the bulk metal forms a primary battery pack with this coating. At a higher interface temperature, the carbon in the brush and the trace moisture in the atmosphere produce carbonated gas, plus compounds such as sulfur and phosphorus suspended in the atmosphere, which become excellent electrolytes and can make this layer in a short period of time. The dural failure and peeling off.
In our long-term research and practice, we have realized that to effectively extend the life of electric brushes, we must abandon conventional practices and create a new way.
In general, the wear resistance of the material is indeed related to its surface hardness, but it also depends on the friction coefficient of the material itself. Different materials have different friction coefficients. If the shape, surface roughness, friction speed, and positive pressure of these materials are all the same, due to the difference in friction coefficient, their friction and material wear conditions will also show significant differences. There is no doubt that the smaller the coefficient of friction, the less friction and material wear.
We regard the commutator(sliding ring) and the brush as a pair of friction pairs. First of all, we should ensure that the commutator(sliding ring) is not or less worn. Under the previous question, the brush is required to have a high conductivity. From the current technology and economic level, this can be done, non-graphite electric brushes are. However, the biggest disadvantage of the graphite brush is that the material is too soft and the friction coefficient is too large. Whether it is sintering brush or die-casting brush, there are such problems.
