In the machining process of thin-walled non-standard precision machining lathe parts, thermal stress deformation is one of the key factors affecting machining accuracy, and choosing the right cutting fluid and cooling method is crucial to controlling thermal stress deformation.
The selection of cutting fluid needs to consider many factors. The first is lubrication performance. When non-standard precision machining lathe parts, the friction between the tool and the workpiece will generate a lot of heat. High-quality lubrication can reduce friction, thereby reducing thermal stress deformation caused by frictional heat. For example, cutting fluid containing extreme pressure additives can form a firm lubricating film on the surface of the tool and the workpiece under high temperature and high pressure, effectively reducing the friction coefficient.
The second is cooling performance. The cooling effect of the cutting fluid can timely take away the heat generated during the machining process to prevent the local temperature of the workpiece from being too high. Water-based cutting fluid has a higher specific heat capacity and stronger cooling capacity, and has obvious advantages in controlling thermal stress deformation. In addition, the adaptability of the cutting fluid to the workpiece material should also be considered. For thin-walled parts of different materials, such as aluminum alloy, stainless steel, etc., some cutting fluids may react chemically with them, affecting the surface quality and dimensional accuracy of the workpiece, so it is necessary to choose a cutting fluid that is compatible with them.
The cooling method should not be ignored either. The internal cooling method is to spray the cutting fluid directly into the cutting area through the channels inside the machine tool spindle and the tool. This method can make the cutting fluid quickly reach the high temperature area, and the cooling effect is significant. It is especially suitable for the processing of complex thin-walled parts such as deep holes and slender shafts, and can effectively reduce the deformation caused by thermal stress concentration. The external cooling method is to cool the cutting area from the outside, such as spray cooling. The spray cooling equipment is simple and easy to operate, but the cooling effect is slightly inferior to the internal cooling.
In practical applications, the gas-liquid mixed cooling method can also be used. The compressed air is mixed with a small amount of cutting fluid and then sprayed into the cutting area. It not only utilizes the rapid heat dissipation characteristics of the air, but also relies on the lubrication and cooling effect of the cutting fluid. While ensuring the cooling effect, it reduces the use of cutting fluid, reduces costs and environmental pollution, and can also play a good role in controlling the thermal stress deformation of thin-walled non-standard precision machining lathe parts.
