La_2O_3/MoSi_2复合微粒对烧结钼组织与力学性能的影响  

Effect of La_2O_3/MoSi_2 Composite Particles on Microstructure and Mechanical Properties of Sintered Molybdenum

作　　者：昝秀颀[1] 王德志[1] 汪异[1] 徐兵[1] 

机构地区：[1]中南大学材料科学与工程学院,长沙410083

出　　处：《机械工程材料》2011年第10期50-53,共4页Materials For Mechanical Engineering

基　　金：国家"863"高技术研究发展计划(2007AA03Z5172008AA031003)

摘　　要：采用机械合金化法制备了La2O3/MoSi2复合微粒,运用固-固掺杂法制备了掺杂不同含量La2O3/MoSi2复合微粒的烧结钼,并对其组织与性能进行了研究。结果表明:La2O3/MoSi2复合微粒的掺杂可细化烧结钼晶粒,有效提高烧结钼的室温抗弯强度和断裂韧度,当其质量分数为2.0%时,断裂韧度可提高101.63%;其高温抗压强度明显提高,但随温度升高而降低,当掺杂质量分数为1.5%时烧结钼的抗压强度在1 000℃时较纯钼的仍可提高近1倍;烧结钼的断裂方式随掺杂量的增加由沿晶断裂向穿晶断裂转变的趋势越来越明显,掺杂质量分数为0.2%时出现的黑色孔洞是导致高温抗压强度降低的原因。La2O3/MOSi2 composite particles were prepared by mechanical alloying method and then to prepare sintered molybdenum with different contents of La2O3/MOSi2 composite particles by solid-solid doping method, and the microstructure and mechanical properties of sintered molybdenum were studied. The results show that the doping of La2O3/MOSi2 composite particles could reduce the grain size of sintered molybdenum, and improve the room temperoture bending strength and fracture toughness effectively. When the doping content of La2O3/MOSi2 was 2.0wt%, the facture toughness was increased by 101. 630//00. High-temperature compressive strength decreased obviously with increase of temperature, but the compressive strength of sintered molybdenum with doping content of 1.5wt% was still enhance by 1 time comparing with pure sintered molybdenum, The trend of from ＇intergranular fracture to transgranular fracture of sintered molybdenum was nore and more obvious with increase of doping. The black hold appeared in sintered molybdenum with doping content of 0.2wt% to make high-temperature compressive strength decrease.

关 键 词：La2O3/MoSi2复合微粒 掺杂 烧结钼 组织 力学性能 

分 类 号：TG146.412[一般工业技术—材料科学与工程]