Laseravausta

Laseravausta is a Finnish term used to describe the removal of material from a solid surface by irradiation with a laser. In many contexts it corresponds to laser ablation, the rapid transformation of laser energy into heat, mechanical stress, and phase changes that eject material. The exact mechanism depends on the laser wavelength, pulse duration, energy, and the properties of the target, and can involve photothermal melting and vaporization, photomechanical spallation, or photochemical decomposition.

The methods rely on delivering energy with focused light to a precise spot. Short-pulse lasers, such as femtosecond to nanosecond systems, often achieve high precision with limited heat diffusion, enabling micromachining and minimal thermal damage. Longer-pulse and continuous-wave lasers are used for broader material removal but typically produce a larger heat-affected zone. Common laser types include CO2 lasers for polymers and organics, Nd:YAG and fiber lasers for metals and ceramics, and ultrafast lasers for delicate or high-precision work. Techniques include laser micromachining, drilling, cutting, surface texturing, and thin-film patterning. In analytical contexts, laser ablation is used to sample materials for spectroscopy, notably in LA-ICP-MS (laser ablation inductively coupled plasma mass spectrometry), enabling elemental analysis of solids.

Advantages of laseravausta include non-contact processing, high precision, and the ability to process complex geometries without chemical reagents. Limitations involve heat-affected zones, potential recast layers or debris, equipment cost, and the need for careful control of process parameters. Safety considerations cover laser hazards, airborne particulates, and the requirement for proper enclosure and ventilation. The technique has a long research history beginning in the 1960s and continues to evolve with advances in ultrafast and high-power laser systems.