The principles of laser surface heat treatment process are, in essence, the postulates of metallurgy that are implemented to conventional steel thermal stage transformation. However, it's still essential to satisfy the three conditions to change steel from austenite to martensite thermally:

Adequate carbon existing in solution at the surface of the steel to transform to the stage of austenite.
The suitable austenitizing temperature has to be accomplished to alter the steel surface to austenite.
Maintaining a suitable cooling rate to transform the current-austenitized surface by quick cooling into martensite.

The depth of hardening will be determined by the steel hardenability and the laser energy chosen in addition to the kind of laser utilized. The principle of laser heat treatment is in how the beam's length can be adjusted to create a ring throughout the surface in connection to its diameter.

The density of laser beams power is usually delivered in watts per square centimeter( W/cm2) and can create a sufficiently high heat pattern at the steel surface. It's a known fact that the laser heat energy is absorbed into a thin band (width of the laser beam), which can generate the heat needed to change that band into the phase of austenite.

The conversion of the austenitic phase into the martensite phase will be reliant on the mass (weight) of the entire body of steel being treated with laser. In other words, a heat-sink routine within the steel will tug the surface heat that is produced into the steel's body. With rapid cooling, the essentials of metallurgy continue to be applicable to change the austenite into martensite.

The depth of hardening is usually achieved as a result of the hardening reaction of the material being treated. Steels that contain low to medium carbon and plain carbon steels won't produce rather significant value. Whereas the moderate and high carbon steels that contain both sufficient carbon and alloying components will react favorably to achieve required hardness values. Below is a brief list of the benefits of laser heat treatment process:

Removal of intricate quenching equipment
Reduced scrap rate
Reduced thermal-process time
Reduced equipment surface-area demands
No pollution
Lower energy costs
Agile turnaround times
Reduced material handling
Reduced distortion
Less residual stress relief
Less risk of surface cracking (providing that All the Proper operational conditions have been fulfilled )

Disadvantage of Laser Heat Treatment process

The drawback of laser heat treatment is the depth of the formed case, which will be shallow (approximately 0.100-inch maximum). Naturally, elevated capital equipment cost is also an added issue. Laser heat treatment process, including surface hardening, is used in numerous other applications, including gun-barrel breech slides, engraving, cutting, and thermal phase transformation.