| Laser cladding technology could strengthened the surface of metal parts,and repaired the parts that surface failure. Moreover, it was gave the base material a new performance, so this technology would became extraordinary important in industry. But the development of laser cladding technology was restrained, because of iron base coating have many defects, such as cracking, oxidation, pore and so on. With magnetic field assistive technology in the application acquired achievement well in compound technology, and the operation of technical magnetization was simple, green, pollution-free. Therefore, the paper was mainly researched on laser cladding iron-based coatings combined with magnetization treatment discuss whether the compound technique could strengthen the cladding and the effectiveness of repaired parts surface performance.The 45 steel that after tempering treatment as substrate material,used self-made magnetic device treated it in advance. Firstly studied the magnetization of substrate material tribological performance and the impact of organization. Secondly, to obtain the best cladding process parameters of the experiment, discussed it excellent of the coating macro quality and performance under different cladding process parameters After got the laser process parameters, before laser cladding magnetic substrate, explored coating tribological performance and the impact of organization of magnetic treatment base material in advance.The results showed that after magnetic treatment, the surface of the substrate hardness have not increased, and the magnetizing frequency too high or too low, the hardness will be a slight declined, but all after dealt with the magnetization of substrate material abrasion resistance was better than not magnetized; after magnetization also reduced the friction coefficient, elaborated the organization. Laser process parameters test showed that the cladding layer forming quality mainly depend on how fast scanning speed, and then was the size of the laser power; Only under the parameters combination of good conditions, the less visible coating porosity, forming quality and abrasion resistance was better. Magnetization-laser cladding compound experiment showed that the substrate after magnetization, on the surface of coating hardness was slightly higher than without magnetization, abrasion resistance have improved, grain group also obtained the further refinement, hard particle distribution was more even. Separated magnetization and magnetization-laser claddingcompound tested have shown that 25 Hz frequency magnetization magnetization effect was best, therefore 25 Hz could be as the best magnetizing frequency under the condition of experiment.Through the Matlab software, according to the w- m fractal function model to simulate the two-dimension contour curve and the three-dimension contour surface, contour shape complexity and fractal parameters was discussed. Two-dimension simulation result showed that the fractal dimension and characteristic scale coefficient was the main influence parameters, and along with the fractal dimension changed from 1.3 to 1.9, simulation of the surface profile curve was more and more complicated that the curve shape and amplitude were changed. For 3 dimension contour surface, with the increase of fractal dimension from2.1 to 2.9, the surface profile morphology obtained more and more complicated as well, the conclusion illustrated fractal dimension was still the main parameter affected the surface contour surface morphology. |
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