(1) Fine grinding
That is, use conventional diamond rubber wheels to grind the surface of titanium and titanium-containing alloy castings. The problem that needs to be paid attention to during grinding is still not to make the castings heat up, not to cause grinding scratches on the casting surface, and to make the entire surface flat and smooth.
(2) Barrel grinding method
The so-called barrel grinding method is to put the processed casting, abrasive, water and additives into a barrel grinding tank, and the grinding barrel rotates and vibrates, so that friction is generated between the abrasive mixture and the processed casting, and the casting surface is grinded smooth and flat. Its characteristics are that it does not produce dust pollution, low labor intensity, and does not produce heat during conventional grinding. At present, Japan has commercialized barrel grinders and abrasives for grinding titanium and titanium-containing alloy castings, other metal castings and plastics for sale. After testing, it has been confirmed that the pk series abrasives have the highest grinding efficiency, but the surface roughness is also the highest. Although the grinding efficiency of SA and B series abrasives is not as good as PK, the surface smoothness of the titanium castings after grinding is the highest. At present, the Fourth Military Medical University has successfully developed the first dental barrel grinder in China.
(3) Mechanical polishing method
Use soft cloth wheels or black brushes of different specifications, dipped in titanium and titanium alloy special polishing paste to polish the surface of titanium and titanium alloy. When polishing titanium castings, it is necessary to completely clear the surface contamination layer of the castings and no new grinding hardening layer occurs, otherwise the ideal polishing effect cannot be achieved. High speed and light pressure are still used during polishing. The author has also experimented with using green polishing paste to polish titanium and titanium alloy castings, and achieved a relatively ideal polishing effect. After polishing, titanium and titanium alloy castings cannot be washed immediately. They must be washed after the surface oxide film is fully formed, otherwise the surface will become darker.
