掺杂氧化铈对钼性能的影响

Effect of CeO_2 on Mechanical Performance of Molybdenum Alloys

为了研究氧化铈对钼烧结的致密化作用以及不同含量氧化铈对钼坯密度、硬度及轧制后力学性能的影响,设计制作了5种掺杂量的Φ17 mm烧结棒,烧结棒全部取样进行密度、硬度检测,做组织形貌观察分析;将烧结棒进行轧制(1250℃热轧),对轧制成的Φ7.2 mm轧杆做拉伸试验及断裂韧性试验。结果表明,氧化铈有强烈细化晶粒的作用,当氧化铈含量增加到3.5%时,晶粒可细化到纯钼的1/4以下;氧化铈掺入量在1.2%~2.5%的范围内时,可以在几乎不降低塑性的前提下同时提高轧制钼制品的抗拉强度和屈服强度;氧化铈掺杂大幅度地提高了钼材的断裂韧性,将材料的断裂韧性提高到纯钼材料的3~4倍以上。

In order to investigate the action of CeO_2 on heightening density of molybdenum sinter and the effect of the performance of molybdenum alloys with different contents of CeO_2,the sintered Φ 17 mm Mo bars doped with CeO_2 respectively were designed and processed,the density and hardness of those bars were tested,and the structure feature was also aoalyzed.The Φ 7.2 mm bars made from Φ 17 mm bars by rolling at 1250 ℃ were tested.As content of CeO_2 increasing,the grain size is thinner;when the content of CeO_2 increases to 3.5%,the grain size may be decreased less than one fourth that of the Mo materials.When the contents of CeO_2 range from 1.2%～2.5%,both yield strength and extension strength of the product are improved at the same time,but the plasticity is not obviously changed.Fracture toughness value of all samples doped with CeO_2 is increased over 3 to 4 times than pure molybdenum.