Study On The Quantitative Analysis And Research Of The Refinement Of The Magnesium Alloy Grains With Laser Shock Processing

Magnesium(Mg) alloy is renewed as the perfect engineering material in the 21st century, for its well-known advantages, such as plentiful reserves, small density, both the high rates of the intensity and rigidity, good conductivity of heat and electricity. But its disadvantages restrict its development such as the low corrosion resistance and wear-resistant as well as the mechanics datas. So, the new surface modification technology of wrought magnesium alloy is of great practical significance to enhance the chemical and mechanical characters. Take the AZ31B magnesium alloy for example in this paper, the rate of Grain Refinement in the enhancement layer by the laser shock processing is studied from the aspects of the theory and the experiment, adopting the technology of Laser Shock Processing ,and using the powerful functions of the graph and calculation.The surface of the magnesium alloy shocked by the Nd:glass short-pulsed laser isn't burnt, but the morphology is kept well and the micro-degree of Finish is improved, the chemical compositions are neither changed clearly, nor new phases. By means of the metallography, the Grain of the magnesium alloy is refined obviously.The given research results only made the qualitative analysis of the grain refinement of magnesium alloy by LSP, but the quantitative analysis of grain refinement ratio of magnesium alloy by LSP is still vacant, so this study emphasizes the creative work on it. In order to calculate the refinement ratio of magnesium alloy grains quantification ally and analyze the changing performance of its mechanism quantification ally, the metallography of the specimens on the shocked and non-shocked area were processed by grey enhancement processing, median filtering processing, binarization processing, mathematical morphological processing and etc, and the average diameter and the area of the grains before and after the laser shock peening (LSP) and the refinement ratio after the LSP were worked out by intercept method and area method. It showed that this method could process the metallographic of magnesium alloy conveniently and quickly, the refinement ratio of grain areas, the average diameters and the refinement ratio of the average diameters before and after the LSP were worked out accurately, and the refinement ratio was 70.43% by quantitative analysis, and the refinement ratio of the area was 71.33%.