Titanium Alloy
Purpose：Observe the microstructure of
titanium alloys. Titanium alloy blades are increasingly replacing aluminum
alloys and precipitation-hardened stainless steels as the preferred material
for compressor blades in aerospace engines due to their exceptional specific strength. These blades must
withstand operational loads at temperatures below 500°C while maintaining high
room-temperature strength and creep resistance. Samples undergo cutting
(Beta-400MA), mounting (FLEXPRESS fully automatic modular hot mounting
machine), grinding/polishing (Alpha610), and etching with Keller’s reagent for
microscopic examination (MN80 metallographic microscope).
Basic
Guide：
Cutting：1.Use
titanium-specific
resin-bonded silicon carbide cutting wheels. Refer to the Trojan Cutting Guide
for specific
models.
2.Select
pulse mode for cutting, with a recommended maximum cutting speed ≤0.25 mm/s.
Mounting：Use
high-edge-retention cold/hot mounting resin.
Grinding：1.Begin
with P400 silicon carbide sandpaper/lapping films/diamond grinding discs until
the sample surface is flat
and cutting damage is fully removed.
2.Continue
fine grinding
with P400, P800, P2000 sandpaper or a POS disc +9µm diamond polishing suspension.
3.Clean
the sample, sample holder, and hands after each grinding step.
Polishing：1.Clean
the polishing cloth, sample holder, and hands before polishing. Repeat cleaning
after each step.
2.Do
not mix polishing disks with different
abrasive particle sizes.
3.Rinse
the sample surface with alcohol and dry with a blower to remove residue.
4.After
each polishing step, inspect under a metallographic microscope to ensure
scratch size matches the abrasive grit and direction is random.
5.Clean
polishing cloths with running water and a soft brush after use, then air-dry.
6.Dedicate
polishing cloths used for titanium alloys exclusively to such samples.
