【摘要】 利用光学显微镜、扫描电镜、X射线衍射仪研究了增强型UNS N08028′合金析出相的分布、形貌和种类。基于扩散理论的应用和具体分析,研究了4种不同固溶温度对试验合金析出相的影响,并确定了合理的固溶处理温度。结果表明,试验合金经过锻造后,形成了以大小不均的奥氏体等轴晶为基体,颗粒状和针状σ相连续分布于晶界和弥散分布于晶内的组织;Mo在γ-铁中的扩散速度决定着σ相的溶解时间,经过1155℃、2 h的固溶处理后,σ相已大部分溶解,试验合金基本形成了单相奥氏体组织。更多还原

【Abstract】 Distribution,morphology and type of the precipitated phase in enhanced UNS N08028′ alloy were investigated by using optical microscope,SEM and XRD.Based on the application and analysis of diffusion theory in detail,four different solution treatment temperatures and their effects on the precipitated phase of the alloy were studied and examined.The results show that the microstructure of the tested alloy as-forged is equiaxed austenite grains with different size of granular and acicular σ phase distributed in the grain and along the grain boundaries.The solution time of σ phase is determined by the diffusion rate of Mo in γ-Fe.The solution treatment was determined as 1155 ℃×2 h with water cooling.The σ phase after such a solution treatment can be completely eliminated,and the final microstructure of the alloy is single phase austenite.更多还原