Pay attention to the problem of machining titanium alloy
In the process of CNC turning and milling titanium alloy, the matters that should be paid attention to are:
(1) Due to the small modulus of elasticity of titanium alloy, the clamping deformation and force deformation of the workpiece during machining are large, which will reduce the processing accuracy of the workpiece; The clamping force should not be too large when the workpiece is installed, and auxiliary support can be added when necessary.
(2) If a cutting fluid containing chlorine is used, it will decompose and release hydrogen at high temperatures during machining, which will be absorbed by titanium and cause hydrogen embrittlement;
It may also cause high temperature stress corrosion cracking of titanium alloys.
(3) The chloride in the cutting fluid may also decompose or volatilize toxic gases when used. Safety protection measures should be taken during processing and use, otherwise it should not be used;
After cutting, clean the parts thoroughly with a chlorine-free cleaning agent in time to remove chlorine residues.
(4) It is forbidden to use lead or zinc-based alloy tools and fixtures to contact titanium alloys, and copper, tin, cadmium and their alloys are also forbidden to use.
(5) All tools, fixtures or other devices in contact with titanium alloys must be clean; The cleaned titanium alloy parts should be prevented from being contaminated by grease or fingerprints, otherwise it may cause salt (sodium chloride) stress corrosion in the future.
(6) Under normal circumstances, there is no risk of ignition when CNC cutting titanium alloys. Only in the micro-cutting, the cut small chips will ignite and burn. In order to avoid fire, in addition to pouring a large amount of cutting fluid, it is also necessary to prevent the accumulation of chips on the machine tool. Replace the tool immediately after it is blunt, or reduce the cutting speed, and increase the feed rate to increase the chip thickness. In case of fire, fire extinguishing equipment such as talcum powder, limestone powder, dry sand, etc. should be used to extinguish the fire. It is strictly forbidden to use carbon tetrachloride and carbon dioxide fire extinguishers, nor to water, because water can accelerate the combustion and even cause hydrogen explosion.