Laser Rust Removal vs. High Pressure Water Gun Rust Removal, which is better?

 The principle of laser rust removal is laser cleaning

 

The process of pulsed Nd: YAG laser cleaning depends on the characteristics of the light pulses generated by the laser and is based on a photophysical reaction caused by the interaction between the high-intensity light beam, the short-pulsed laser light, and the contaminated layer. The physical principle can be summarized as follows:

 

a) The beam emitted by the laser is absorbed by the contaminated layer on the surface to be treated.

b) The absorption of the large energy creates a rapidly expanding plasma (highly ionized unstable gas), which generates a shock wave.

c) The shock wave causes the contaminants to fragment and be removed.

d) The width of the light pulse must be short enough to avoid the heat buildup that destroys the treated surface.

e) Experiments have shown that plasma is generated on metal surfaces when oxides are present on the surface.

 

Plasma is only generated at energy densities above a threshold which depends on the contamination or oxidized layer being removed. This threshold effect is important for effective cleaning while keeping the substrate material safe. There is also a second threshold for the appearance of plasma. If the energy density exceeds this threshold, the substrate material is destroyed. For effective cleaning with the safety of the substrate material, the laser parameters must be adjusted to the situation so that the energy density of the light pulses is strictly between the two thresholds.

 

Each laser pulse removes a certain thickness of contamination layer. If the contamination layer is thicker, more than one pulse is required for cleaning. The number of pulses required to clean the surface depends on the degree of surface contamination. An important consequence of the two thresholds is the self-control of the cleaning. Light pulses with an energy density higher than the first threshold will keep rejecting contaminants until they reach the substrate material. However, because the energy density is below the damage threshold of the substrate material, the substrate will not be damaged.

 

Sandblasting and high-pressure water gun rust removal principle are actually similar, the main or spray of diamond sand impacts the surface to achieve the purpose of rust removal, The sandblasting process:, is the use of compressed gas, high-speed pneumatic pressure way of spraying the spray material (commonly used spray material copper ore sand, quartz sand, diamond sand, iron sand, Hainan sand, etc.) to the surface of the workpiece in the spray material on the surface of the workpiece under the impact, and cutting, so that the surface to obtain a certain degree of Cleanliness (such as rust removal). High-pressure water gun that is water and sand together with the spray, if not add sand to remove rust or more difficult. That kind of ordinary cleaning machine is not possible.