| Maraging stainless steel has considered as a new type of stainless steel that is widely usedin electronics, aerospace, nuclear power industry and other fields due to its excellentmechanical properties. For the practical application, heat treatment and welding play animportant role in the utilization of maraging stainless steel. In addition, one strategy toachieve high-quality welding is to use laser welding.0Cr13Ni7MoTi maraging stainless steel has well corrosion resistance, heat resistance andmechanical properties. In this paper, the main aim is to study the characteristics of heattreatment, laser welding and high temperature oxidation of the0Cr13Ni7MoTi maragingstainless steel.To research the influence of parameters of solution treatment and aging treatment for0Cr13Ni7MoTi maraging stainless steel, this steel is deal with solution and aging treatment indifferent temperatures and times. As a results, the highest aging hardness is achieved atdifferent aging temperatures after1050℃and850℃solution treatment, respectively. Inaddition, the reversed austenite will be generated when the aging temperatures at540℃orupper.In this paper,5welding speeds are used. Moreover, in order to improve the mechanicalproperties of the welding joints, aging treatments at different temperature are also applied.The hardness of welding joints consistent with―W‖, meanwhile, the hardness of fusion zoneand heat affected zone decreased greatly. The best properties of joints were achieved aswelding speed is2.5m/min. However, compared with the parent material, the yield strength isrelatively low, only76.9%, and has strongly brittle fracture tendency. After420-580℃agingtreatment, the enhanced hardness and strength of welding joints were obtained. Moreover, thetrends of joints were different, and the highest hardness were achieved in fusion zone, heataffected zone and unaffected parent material zone at500℃,460℃and420℃respectively.The recycle oxidation tests were carried out at450℃，500℃，550℃, and600℃usingthe Maraging stainless steel though850℃solution treatment for1h. The morphology,element distribution and hardness variation of oxidation film were studied by SEM and XRD.The recycle oxidation results show that there is no obviously weight increasing, which according to―complete antioxidant rating‖. The color of oxidation film was changed fromgolden to dark blue and the surface roughness was raised with the temperature increase. Asthe oxidation temperature at500℃or elevated temperature, the tumor-like protuberances onthe surface of oxide film are rich containing C and Mo element but Cr and Fe are poor. Foroxidation film, the higher of the oxidation temperature, the lower of the hardness, and at550℃or elevated temperature, the hardness of oxide film is lower than that of the parentsmaterial. |
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