Study On Process For Intensive Laser Additive Maintenance Of Fe314 In Field Environment

As an advanced maintenance method in the field of equipment maintenance,the laser additive maintenance technology is a suitable maintenance method for the equipment maintenance support in the field environment with its particular technical features.Faced with the multi-material characteristics of the failure parts and the time-validity request of maintenance,the laser additive maintenance technology cannot repair the failure parts with the same material,the laser additive maintenance technology cannot repair the failure parts with the same material.And there is still a problem of repairing materials shortage.In order to solve this problem,this study based on the intensive laser additive maintenance that repairing various kinds of materials of failure parts with Fe314.This study has advantages of improving the mobility and flexibility for the field additive maintenance equipment,reducing the maintenance cost of the field damaged equipment,expanding the application range of the laser additive maintenance technology in field environment,and promoting the popularization and application of laser additive maintenance technology.First of all,the effects of different atmospheres,nitrogen atmosphere and air atmosphere,on the microstructure and properties of Fe314 formed by the laser additive manufacturing were conducted via studying on density,element composition,defect characteristics,microstructure and mechanical properties of experimental specimens.The conclusion is drawn which is feasible to make Fe314 as the material for laser additive maintenance in the air atmosphere of field environment.There is no influence on microstructure and properties of Fe314 formed by laser additive manufacturing in the different atmosphere.Moreover,the microstructure and properties of Fe314 formed by laser additive manufacturing are gained to lay a foundation for the further research.Secondly,Analyzing the process matching performance based on process parameters of the Fe314 laser additive forming between repairing material and matrix materials to assure a full metallurgical bonding.The process matching performance which belongs to the Fe314 and five different matrix materials was evaluated with taking defect distribution,microstructure distribution,hardness distribution and element gradient near the bonding surface as the evaluation criterion,and the optimal matched process parameters were obtained respectively,which can serve as a guidance meaning for process in studying on the mechanical properties of the intensive laser additive maintenance.Finally,experimental studies on the intensive laser additive maintenance were carried out,using optimal matched process parameters,and the properties of the repaired were studied,and the morphology of fracture was observed.The mechanical behavior,fracture cause and mechanical matching performance of the repaired were analyzed.The validity of optimal matched process parameters was verified,determining whether the mechanical properties repaired satisfy the request for utilization that above 90% of mechanical properties,moreover,the process parameters of intensive laser additive maintenance were obtained.