Uncovering the secrets of how lasers "tame" titanium alloys: the perfect combination of materials science and optical engineering

2025,07,18

Q1: Titanium Alloy is known for its high hardness and is difficult to process with traditional tools. How does laser achieve precision cutting?

　　A: Laser cutting adopts the "energy crushing" strategy. Although titanium alloy has high hardness, the laser beam can generate an energy density of 10⁶–10⁸W/cm² at a very small focal point (about 0.1mm in diameter), instantly heating the material to above 1668℃ and directly vaporizing or melting it. With the help of argon/nitrogen to blow away the molten metal, precision processing with a slit width of only 0.1mm can be achieved without tool wear problems.

Q2: Titanium has a laser reflectivity of up to 90%. Will it damage laser equipment?

A: This requires three key technological breakthroughs:

(1) Wavelength optimization: CO2 lasers are easily reflected, while fiber lasers can increase the absorption rate of titanium to more than 60%;

(2) Reflection protection: The laser head is equipped with a special coating filter to absorb or deflect reflected light;

(3) Pulse control: Nanosecond/picosecond ultra-short pulses are used to achieve "cold processing" - the action time of each pulse is shorter than the thermal diffusion time of the material, reducing heat accumulation.

Q3: Titanium alloy has low thermal conductivity. How to avoid deformation and oxidation during laser precision cutting?

A: Through triple precision temperature control technology:

(1) Dynamic focusing: Real-time adjustment of laser focus position to avoid excessive energy concentration;

(2) Gas optimization: Helium cooling effect is 4 times that of nitrogen, which can increase cooling rate and reduce heat affected zone;

(3) Post-processing: After cutting, pickling with hydrofluoric acid-nitric acid mixture can completely remove the oxide layer.

Q4: What is the effect of laser precision cutting technology in practical applications?

A: Take aviation titanium alloy parts as an example:

(1) Precision: The tolerance of laser precision cutting is ±0.01mm, which is far higher than wire cutting (±0.1mm);

(2) Efficiency: Laser cutting is about 20 times faster than traditional processing;

(3) Quality: The heat-affected zone is controlled within 50μm to avoid the transformation of β phase to brittle α phase.

Conclusion: Laser cutting has achieved three major breakthroughs: "energy density breaks hardness, wavelength regulation overcomes reflection, and dynamic temperature control solves thermal sensitivity", allowing "difficult-to-process materials" such as titanium alloys to achieve micron-level precision manufacturing. This is a model of "using softness to overcome hardness" in modern industry.

Author:

Mr. Aaron Shen

E-mail:

shenguanlun9696@gmail.com

Phone/WhatsApp:

+86 13709173123