Titanium alloy processing requirements for machine tools

Titanium alloys are characterized by high strength and poor thermal conductivity. In order to achieve cutting efficiency like processing aluminum, it is necessary to improve the cutting parameters as much as possible, that is, increase the gold feed and cutting depth, resulting in an increase in the machining cutting force, which may cause static deviation between the workpiece and the tool, and then cause the shape accuracy of the part to deteriorate or the processing process is unstable, but also speed up the wear of the tool. For this reason, the machine tool used for titanium alloy processing must have high power and the best possible static and dynamic characteristics (high static and dynamic stiffness); It is also necessary to be equipped with the corresponding high-pressure cooling and lubrication equipment in order to remove the chips in time in the case of low speed and high torque processing, to reduce tool wear and reduce the heat generated during the processing to the tool, in order to improve the rigidity of the machine tool, some machine tool manufacturers use the box structure or the welded steel structure of the closed frame; The feed shaft is driven by a high-power feed motor and a high-stiffness gackless steering system, which can be clamped to the machining position to further improve the stiffness of the machine. In addition, the rigidity of the entire system, including the spindle-tool-link position and the tool holder, must be improved during machining.

In addition to static stiffness, the dynamic characteristics of the machine are also decisive for the successful machining of titanium alloys. Controlling the stability of the process is a huge challenge. If the rigidity of the machine tool is low and the damping characteristics are poor, self-excited vibration may occur due to the dynamic effects of large cutting force, low speed and excitation frequency similar to the machine tool's own natural frequency, resulting in machining process chatter. In addition to affecting the surface quality of the workpiece (there are vibration lines), this chatter will also cause damage to the machine structure, tool and tool overload. Tool wear increases or even breaks. The stability of the machining process mainly depends on the selected spindle speed, cutting depth and other parameters. To understand the performance of the machine tool and the possible limit cutting depth, the user can also actively take anti-vibration measures such as adding vibration pads to the machine tool and pre-placing parameters in the machine tool control device to avoid the small rotation range of the limit cutting depth to further improve the shock resistance of the machine tool.

The cutting of titanium alloy belongs to strong cutting, so the tool spindle of the machine tool should have a large driving power and a high-power strong cutting function. In the aviation industry, the processing of titanium alloy components to cavity milling, in order to facilitate the removal of chips, to manage the cooling lubrication device, in order to facilitate the removal of chips, to manage the cooling lubrication device, so that a large number of high-pressure cooling lubricants directly spray the cutting edge of the cutting tool. In this way, on the one hand, the tool is cooled, and on the other hand, the chips can be better rushed out of the processing area in time, so as to avoid the chips being cut multiple times and reduce the tool life and scratch the machining surface. In order to make the machine tool with high-power cutting function, the German Heller company targeted design, do not know the machine tool structure and coordinate axis structure, and equipped with a strong cutting swing unit with excellent stiffness installation tool spindle, so that the machine tool can produce the same cutting power at any Angle in vertical, horizontal and space.

In short, the machine tool for processing titanium metal requires high power, high stiffness, with a large flow and high-pressure cooling device, and also good proximity.