Laser shock method and laser shock device

Abstract

The invention discloses a laser shock method and a laser shock device. The laser shock method comprises the following steps that: 1, a laser beam acts on an energy absorption coating coated on the surface of a metal workpiece; 2, the energy absorption coating absorbs laser energy and then is gasified to form a plasma; 3, the plasma continues to absorb the laser energy and then explodes to eject charged particles so as to form shock waves; and 4, an external magnetic field imposes the acceleration facing the metal workpiece on the charged particles so as to increase the action force of the shock waves on the metal workpiece. By the method and the device, the intensity of the shock waves can be increased so as to perform contactless constraint on the plasma, so that the shock effect is improved and the environmental pollution is avoided.

Description

technical field [0001] The invention relates to the technical field of mechanical manufacturing and laser shock strengthening, in particular to a laser shock method and a device thereof. Background technique [0002] Laser shock strengthening technology is a high-tech technology that uses plasma shock waves generated by strong laser beams to improve the fatigue resistance, wear resistance and corrosion resistance of metal materials. It has outstanding advantages such as non-contact, no heat-affected zone, strong controllability and remarkable strengthening effect. [0003] figure 1 A schematic diagram of the existing laser shock strengthening, such as figure 1 Shown, high power density (GW / cm 2 order), short pulse (10-30ns order) laser beam 101 acts on the energy-absorbing coating 104 coated on the surface of the metal workpiece 106 through the transparent confinement layer 103, the coating 104 absorbs the laser energy and vaporizes rapidly and A large amount of dense hi...

AI Technical Summary

Problems solved by technology

However, as a rigid material, the glass constrained layer has extremely poor adaptability to constrained planes, especially for laser shock advantages, such as micro-holes, corners and other local areas, and non-planar areas cannot be applied; and the operation is difficult, and it needs to be used every time it is impacted. Replacing the constraining layer once is also very expensive and can only be applied to the laboratory research stage

In addition, glass, as a brittle material, bursts and sputters after being subjected to the action of plasma shock waves, which poses a certain degree of danger to operators and lasers

[0011] In order to solve the problem of poor adaptability of the glass constrained layer, many people are also working on the research and development of flexible confinement technology, including water, flexible film, silica gel, PVC film, resin constrained layer, ice confinement and other means, but so far there is no Which kind of constraint layer can achieve breakthrough progress has not been widely recognized by everyone

[0012] In addition to problems such as the adaptability and operability of the confinement layer, the lateral expansion of the plasma greatly weakens the peak pressure of the plasma shock wave, which has a strong negative impact on the shock effect

However, none of the existing confinement technologies can limit the lateral expansion of plasma, and studies have shown that the more flexible the confinement layer, the better its adaptability, but the corresponding lateral expansion effect is also more obvious, so the confinement effect and adaptability A pair of irreconcilable contradictions are formed, and new restraint technology is urgently needed to solve this problem

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