SLM制备马氏体时效不锈钢组织及服役行为  

Microstructure and service performance of maraging stainless steel prepared by SLM

作　　者：赵晓洁 赵凯 张轩 高扬[1] ZHAO Xiaojie;ZHAO Kai;ZHANG Xuan;GAO Yang(Department of Intelligent Control and Equipment,Research Institute of Petroleum Exploration and Development,Beijing 100083,China)

机构地区：[1]中国石油勘探开发研究院智能控制与装备研究所,北京100083

出　　处：《钢铁》2024年第6期145-154,共10页Iron and Steel

摘　　要：马氏体时效不锈钢具有高强度及耐腐蚀等优点,在航空航天及石油等领域应用广泛。以选区激光熔化(SLM)技术制备马氏体时效不锈钢为研究对象,开展力学性能及腐蚀磨损性能测试。采用OM、SEM、EBSD、TEM及三维形貌仪等表征手段分析马氏体时效不锈钢的微观组织及服役行为。结果表明,选区激光熔化技术制备的马氏体时效不锈钢力学性能优异,屈服强度和抗拉强度分别为700 MPa和1184 MPa,伸长率和冲击韧性分别达到20.6%和149.6 J。对拉伸和冲击断口表面形貌分析,均表现为细小蜂窝状的韧窝,断裂形式为韧性断裂。在腐蚀磨损条件下,马氏体时效不锈钢的失效形式以磨粒磨损、腐蚀磨损为主。研究不同载荷下马氏体时效不锈钢的腐蚀与磨损交互作用,发现磨损对腐蚀的促进作用随载荷增加而增强,主要由于存在“应变差电池”。马氏体时效不锈钢微观组织主要由马氏体以及少量奥氏体组成,组织细小,且内部有高密度位错及纳米尺寸夹杂物存在。分析氧化铝夹杂物对马氏体时效不锈钢服役行为的影响,发现微纳米尺寸球形夹杂物可有效调控马氏体不锈钢韧性和腐蚀磨损性能。Maraging stainless steel exhibits high strength and good corrosion resistance,widely used in aerospace,and petroleum fields.The mechanical properties and corrosion wear properties of maraging stainless steel prepared by selective laser melting(SLM)were tested.Microstructure and service behavior of the samples were analyzed by OM,SEM,EBSD,TEM and Three-dimensional morphometer.The results show that the mechanical properties of the maraging stainless steel prepared by selective laser melting technology are excellent.The yield strength and tensile strength are 700 MPa and 1184 MPa,and the elongation and impact toughness are 20.6%and 149.6 J,respectively.The tensile and impact fracture surface morphology shows fine cellular dimple,and the fracture mode is ductile fracture.The main failure modes under tribo-corrosion are abrasive wear and corrosion wear.The interaction between corrosion and wear of maraging stainless steel under different loads is studied,and it is found that the promotion of wear to corrosion increases with the increase of load,mainly because of the existence of"strain difference battery".Maraging stainless steel is mainly composed of martensite and a small amount of austenite,with fine microstructure,high density dislocations and nano-sized inclusions.The influence of alumina inclusions on the service behavior of maraging stainless steel was analyzed.It was found that micro-nano sized spherical inclusions could effectively manipulate the toughness and tribo-corrosion properties.

关 键 词：马氏体时效不锈钢 选区激光熔化 夹杂物 韧性 腐蚀磨损行为 

分 类 号：TG142.71[一般工业技术—材料科学与工程] TG665[金属学及工艺—金属材料]