摘要
利用冲击试验机、维氏硬度计、金相显微镜、扫描电镜和能谱分析技术研究工业生产大型锻件马氏体耐热钢中的δ-铁素体含量以及δ-铁素体对冲击性能的影响。研究表明:δ-铁素体是一种富W、Mo、Cr和V且贫Mn相,接近水口端比冒口端含量高,它的存在是造成马氏体耐热钢冲击韧性低的主要原因。可通过控制铁素体形成元素到最低限和奥氏体形成元素到最高限,抑制δ-铁素体的析出,获得完全马氏体组织及良好的综合力学性能。
Although such steel normally have a fully martensitic microstructure,they are susceptible to the formation of δ-ferrite.δ-ferrite and its effect on impact property in large-scale martensitic heat resistant steel were researched via impact test,Vickers hardness test,optical microscope,SEM and EDS.The results indicated that,δ-ferrite was W,Mo,Cr and V-enriched but poor-Mn phase,and there was more δ-ferrite in water slot than that in feeder head.Its existence led to extremely low impact toughness.A fully martensitic microstructure and excellent general mechanical property could be achieved through controlling the austenitic-formation elements to lower limit and ferrite-formation elements to upper limit.
出处
《一重技术》
2011年第2期31-35,共5页
CFHI Technology
关键词
马氏体耐热钢
Δ-铁素体
Creq
冲击性能
martensitic heat resistant steel
δ-ferrite
Cr equivalent
impact toughness
