Experimental Research Of The Laser Surface Modification For GCr15 Bearing

The bearing is one of the general used parts that extensive applied in the modern machine, and make important use to support the machine property of whole system. It is the whole acceptance parts of system; the life span of the bearings takes decisive influence on the function of whole system, sometimes still decide safe problem of the whole system. The exaltation of the bearings machine property is the most important thing for enhancing the whole system machine property.The thesis is mainly on the research that changes the surface property of GCrl5 bearings steel by laser. Firstly, it makes certain the parameters of laser and the design of research. Among them, the no overlap scan style is chose as the way for laser scan, and the characteristic of the light spot under focus offset condition is chose as complementarities, then getting the more even hardening layer; the each of parameters (output power, value of focus offset and velocity of scan) divides to five levels in some bound. On the analysis of comparison of research ways, three factors-five horizontal orthogonal experiments are designed.The next in order, measure the degree of hardness with the DMH-2LS microhardness instrument, the pressure chooses the 50gf. Measure the value of hardness on the layer depth direction and harden layer, and analyzed the result of experiment.Then, using the MEF3 metallographical microscope to analysis the details of GCr15 bearings surface organization that property has changed by laser. The organization is divided into five layers generally: the melted layer, the complete harden layer, the transitional layer and the base body organization. And make conclusion that the main reason of the superiority is to get the more small martensite organization by analysis the surface that changed by laser.Finally, using three electrode systems to do the erode resisted experiment on electrochemistry, draw the outline of polarization curve by using the CP5-1 synthetically testing erode resisted instrument and Princeton electrolysis slot. The result are: the erode resisted property of surface that changed by laser enhance 1.47% when output power is 120W, enhance 5.51% when output power is 160W,enhance 8.5% when output power is 200W, and the more degree of hardness induce the higher ability of erode resisted property.The methods that integrate the style of no overlap scan with the status of laser light spot is used, improving the hardness uniformity on hard belt. Making the foundation research apply to actual production, and compared the erode resisted property, the theories thatobtained base on the trial are provided for surface property changing and application of GCrl5 bearing.