MA956 is an iron-chromium-aluminum (FeCrAl) based oxide dispersion strengthened (ODS) alloy produced by mechanical alloying. The alloy was irradiated in the Advanced Test Reactor (ATR) at 328 °C up to 4.36 dpa with both thermal and fast neutrons. The microstructures before and after irradiation were investigated by various TEM techniques. The size and number density of dislocation loops, voids, and oxides were analyzed. The results showed that both 1/2<111> and <100> loops were generated in irradiated materials. The number density of dislocation loops reached up to 7.17 × 10²¹/m³. Cavities/voids were formed during irradiation. Argon bubbles were observed in unirradiated materials attached to the surface of oxide particles. The swelling rate was estimated to be 0.08% without subtracting pre-existed Ar bubbles. The oxide particles could maintain crystal structure during irradiation. The oxides had small decrease in size but half reduction in number density after irradiation. Calculation estimated that <100> loops and dislocation lines contributed most to hardening. Alpha prime precipitates were suggested to be formed by comparing to the calculated hardening. Dislocation lines are demonstrated not forming tangles in irradiated specimens.

MA956是通过机械合金化生产的铁铬铝（FeCrAl）基氧化物弥散强化（ODS）合金。合金在328°C的先进测试反应堆（ATR）中用热中子和快中子辐照，最高4.36 dpa。通过各种TEM技术研究了辐照前后的微观结构。分析了位错环，空隙和氧化物的大小和数量密度。结果表明，在受辐照的材料中均产生了1/2 <111>和<100>回路。位错环的数量密度达到7.17×10 ²¹ / m ³。照射期间形成空洞/空隙。在附着于氧化物颗粒表面的未辐照材料中观察到氩气气泡。溶胀率估计为0.08％，而未减去预先存在的Ar气泡。氧化物颗粒可以在照射期间保持晶体结构。辐照后氧化物的尺寸减小很小，而数密度减小了一半。计算估计<100>环和位错线对硬化的影响最大。与计算的硬化相比，建议形成Alpha沉淀。错位线显示在辐照的样品中不会形成缠结。