铝对高铝铁素体耐热钢组织与性能的影响

 高铝铁素体耐热不锈钢作为一类新型的低成本结构材料,主要应用于超临界和超超临界火电机组行业。为了明确铝元素对此类钢种的影响机理,在X10CrAlSi18钢种的基础上,通过成分优化设计,调控铝质量分数,得到两种不同成分的铁素体耐热不锈钢。借助金相显微镜(OM)和扫描电子显微镜(SEM)对微观组织进行表征,并通过硬度测试和拉伸试验测试其力学性能。结果表明,随着铝质量分数的增加,促进了再结晶过程,晶粒细化;并且铝元素降低了碳元素的扩散速度,抑制碳化物的析出聚集;随着铝质量分数的增加,材料的抗拉强度、屈服强度和硬度升高,伸长率降低。

Effect of aluminum on microstructure and properties of high alumina ferritic heat resistant steel

High-aluminum ferritic heat-resistant stainless steel as a new type of low-cost structural material is mainly used in the supercritical and ultra-supercritical thermal power generation.In order to clarify the mechanism of the effect of Al on the steel property,Al mass percent based on X10CrAlSi18 steel and obtained two different compositions of ferritic heat-resistant stainless steel was optimized. The microstructure was characterized by means of metallographic microscope (OM) and scanning electron microscope (SEM),and its mechanical properties were measured by hardness test and tensile test. The experimental results show that the increase of Al mass percent facilitates the recrystallization process and grain refinement.The Al element reduces the diffusion rate of carbon and inhibits the precipitation and aggregation of carbides. Besides that,with the increase of Al mass percent,the tensile strength,yield strength,and hardness of the material are improved,and the elongation is decreased.