What technical measures are needed for CNC lathe processing of high hardness materials?

Analysis of technical measures for CNC lathe processing of high-hardness materials
In the field of mechanical manufacturing, with the improvement of product structural strength requirements, the demand for processing high-hardness materials continues to grow. Such materials include hardened steel, alloy tool steel, stainless steel, high-speed steel, titanium alloy, etc., which have high hardness, large cutting resistance, and high processing temperature, which can easily cause problems such as increased tool wear, reduced workpiece surface quality, and reduced processing efficiency.

Reasonable selection of tool materials and geometric parameters
The primary factor in processing high-hardness materials is tool selection. Traditional high-speed steel tools are prone to rapid wear in the processing of high-hardness materials, so high-performance tool materials such as cemented carbide, ceramics, cubic boron nitride (CBN) or polycrystalline diamond (PCD) need to be selected. Among them, CBN tools are particularly suitable for workpieces with a hardness of HRC50 or above.
In addition to the material itself, the optimization of tool geometric parameters is also extremely critical. For example, the tool rake angle should be appropriately reduced to enhance the cutting edge strength; the back angle design should take into account chip removal and tool support; the main deflection angle can affect the direction of the cutting force, and reasonable setting helps to reduce tool force concentration and thermal deformation.

Reasonable setting of cutting parameters to reduce load
Cutting parameters have a significant impact on tool life and processing quality. When processing high-hardness materials, a strategy of low cutting speed, small feed rate and small cutting depth should be adopted to reduce the accumulation of cutting heat and tool wear rate per unit time.
For example, when processing high-hardness steel, CBN tools can use a cutting speed of 20-100 m/min, and the feed rate is controlled within the range of 0.05-0.15 mm/rev. High speed and large feed should be avoided to avoid tool burning and thermal deformation of the workpiece.

Enhance cooling and lubrication, control cutting temperature
When processing high-hardness materials, heat is concentrated, and the role of the cooling system is more important. A high-pressure coolant system should be used to accurately spray the coolant to the contact area between the tool and the workpiece to quickly take away the cutting heat and prevent annealing or burning of the hardened layer on the workpiece surface.
The use of high-efficiency cutting fluids containing additives can form a stable lubricating film between the tool and the workpiece, reduce friction and adhesion, and improve the processing surface quality and tool life. At the same time, for special materials such as titanium alloys, you can also try to use oil-based coolants or a combination of dry cooling + cold air systems.

Use high-rigidity equipment and stable clamping systems
When CNC lathes process high-hardness materials, the rigidity and stability of the equipment itself are particularly important. It is necessary to ensure that the bed structure has sufficient seismic resistance, the guide rails and lead screws are of high precision, and the tool holder is stable and firm. In addition, a high-precision spindle bearing system should be used to avoid radial runout during processing.
In terms of clamping, a clamping method with uniform clamping force and small deformation should be selected. For workpieces with high precision requirements, a three-jaw chuck with soft jaws or a customized special fixture can be used to ensure that the workpiece will not be affected by clamping deformation during processing. Size and surface quality.

Process strategy and multi-pass processing allocation
For materials with higher hardness, it is not advisable to remove all the excess at one time. A multi-pass rough and fine separation processing strategy can be adopted. First, rough turning is performed to remove most of the excess, and then semi-finishing and fine turning processes are performed to ensure the final size and surface quality. Reasonable process parameters should be set for each process to maintain the stability of the processing process.
It can also combine intermittent cutting technology, milling instead of turning and other strategies to disperse cutting heat and cutting force, and avoid heat accumulation and tool damage caused by long-term continuous processing.

Application of CNC program optimization and monitoring system
The programming of CNC lathe processing also needs to adapt to the characteristics of high-hardness materials. CAM software can be used to simulate and analyze the path to avoid sudden changes in cutting angles or sharp acceleration and deceleration that lead to unstable processing. During the processing, the introduction of intelligent monitoring modules such as spindle load, tool temperature, and vibration monitoring helps to grasp the tool status and processing quality in real time.
Some high-end CNC lathes also have tool compensation and wear prediction functions, which can warn before the tool is abnormal, replace or adjust processing parameters, and reduce abnormal downtime and scrap rate.