摘要
使用原位自生法制备出4种TC18钛基复合材料。结果表明,热处理过程中随着增强体含量增加,β晶粒的合并速度加快,且β晶粒的尺寸分布标准差呈现下降的趋势,该组织现象与增强体对β晶界迁移的影响有关。增强体对晶界迁移钉扎能力的下降是导致该细化规律的首要原因。TiB和TiC摩尔比为4:1的复合材料在拉伸试验中塑性俱佳,但是屈强比却均高于0.96,且随着增强体含量增加呈现增加的趋势。拉伸过程中晶界对位错的吸收致使位错强化增加减缓,增强体加速了晶界对位错的吸收从而导致了上述结果,也正因为如此,晶粒细化对增韧作用的贡献会随着增强体含量增加而增加。
Four different kinds of TC18 Ti matrix composites containing trace amounts of TiB and TiC were fabricated by in-situ synthesis method.Results show that the merging of β grain is accelerated with increasing the reinforcements during heat treatment,and the standard deviations of β grain size distribution tend to decrease.The microstructure phenomenon is associated with the influence of the reinforcements on the boundary migration of β grains.The pinning ability of the reinforcements to the grain boundary migration decreases,which plays the most important role in the micro structure refinement.The plasticity of the composites is excellent during tensile test.However,when the molar ratio of TiB to TiC in the composites is 4:1,the yield ratios of the composites are all higher than 0.96,and gradually increase with the increase of the reinforcements.The grain boundaries absorb the dislocations,which slows down the increase of dislocation strengthening during the strengthening process.It is suggested that the reinforcements accelerate the absorption of dislocations,and thus lead to this result.The contribution of the microstructure refinement to the toughness increases with the increase of reinforcements.
作者
孙曙宇
吕维洁
Sun Shuyu;Lv Weijie(Taizhou University,Taizhou 318000,China;State Key Laboratory of Metal Matrix Composites,Shanghai Jiao Tong University,Shanghai 200240,China)
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2020年第2期398-403,共6页
Rare Metal Materials and Engineering
基金
Taizhou Science and Technology Project(1702gy07)。
作者简介
孙曙宇,男,1971年生,博士,台州学院医化与材料工程学院,浙江台州318000,电话:0576-88660358,E-mail:sun_shuyu@126.com。
