How to avoid easy "burning" and "explosion" when cnc machining magnesium alloys
Cnc machining magnesium alloys problem
|Magnesium-based sheet metal processing in the precision parts processing stage, the resulting fine chips and fine powder can easily reach the ignition temperature and cause burning or explosion accidents. The size of the chips generated in the initial processing stage is large. Due to the high thermal conductivity of magnesium, the frictional heat generated can be quickly dissipated, so it is difficult to reach the ignition temperature. In this stage, the accident occurs less.|
1. Control the cutting speed.
The cutting heat of magnesium alloy precision parts will increase in proportion to the cutting speed, so the cutting speed has a great influence on the cutting temperature. In actual work, the cutting heat generated by different cutting speeds will change the color of the surface oxide film of the chips. Therefore, a safe cutting speed can be estimated by cutting the color of the oxide film by the magnesium alloy at different cutting speeds.
2. Correct selection of cutting fluid.
Unless the machine construction itself is limited, the cutting fluid should always be supplied in the magnesium alloy process and the chip temperature should be reduced. Considering the chemical properties of magnesium, the choice of cutting fluid should avoid the use of flammable, highly oxidizing and high water content liquids, thus preventing the coolant from burning in high temperature magnesium dust or reacting to exothermic fire.
In addition, lubricating oil, hydraulic oil, guide oil, and spindle oil used in machine tools are mostly flammable liquids, and the general oil storage capacity is not small. Therefore, magnesium alloys should be specially inspected before precision parts processing, and whether there is oil leakage at each position of the machine tool. Seepage oil, prevent it in advance.