2 results about "Residual compressive stress" patented technology

According to the method for improving the quality of the inner wall of the laser-processed micropore based on the dual cavitation effect, post-treatment strengthening is conducted on the laser-processed micropore based on the dual cavitation effect of laser cavitation and ultrasonic cavitation, and a large number of cavitation bubbles can be generated through the dual cavitation effect; the residual tensile stress on the inner wall of the micropore is changed into pressure stress by the local shock wave effect generated by cavitation collapse, the distribution of the residual pressure stress on the inner wall of the micropore can be improved, the generation trend of microcracks on the wall of the micropore is reduced, and the generation of the microcracks is effectively reduced or even prevented, so that the mechanical property of the micropore area is effectively improved. The laser cavitation is precisely positioned in a micropore processing area, so that the cavitation strengthening effect on the micropore inner wall area can be ensured. A large number of cavitation bubbles can be generated through ultrasonic cavitation, and the defect that the number of the cavitation bubbles is small under the laser cavitation effect is overcome. According to the method, a water temperature adjusting mode is adopted, the maximum diameter value of the cavitation bubbles is reduced, and the cavitation effect is more obvious and effective. In addition, the ultrasonic vibration also has the effects of ultrasonic cleaning and grain refinement, so that the defects caused by laser drilling are further reduced, and the application field of laser drilling is widened.