摘要
在不同温度进行再结晶退火的W-Y_(2)O_(3)复合材料和去应力退火态纯W的拉伸实验并观察其断口的显微组织,研究了添加稀土氧化物Y_(2)O_(3)对W材料力学性能的影响。结果表明,在300~800℃拉伸W-Y_(2)O_(3)和纯W,随着拉伸温度的提高其抗拉强度都逐渐降低,伸长率先提高后降低。随着拉伸温度的提高W-Y_(2)O_(3)复合材料和纯W的拉伸行为都遵循“脆性”“伪塑性”“本征塑性”的韧脆转变过程;在相同温度拉伸,W-Y_(2)O_(3)的高温塑性比纯W的好。在600℃拉伸时W-Y_(2)O_(3)的塑韧性最佳,其断后伸长率可达~46%。拉伸曲线表明,W-Y_(2)O_(3)出现塑性行为的温度在300℃附近而纯W出现塑性行为的温度在400℃附近。应变硬化阶段的本构方程表明,纯W遵循Hollomon's方程的幂函数强化行为,而W-Y_(2)O_(3)在均匀塑性变形前期表现出对数函数强化行为,在均匀塑性变形后期与纯W的幂函数强化行为相同。这表明,添加稀土Y_(2)O_(3)可提高W材料的塑韧性、降低脆性和韧脆转变温度。
Tungsten and tungsten-based materials are one of the most promising candidate of the first wall material faced plasma atmospheres for future nuclear fusion devices,and their brittleness and mechanical properties have always been the focus of attention.Herein,the tensile behavior at 300~800°C of W-Y_(2)O_(3)composites after recrystallization annealed at different temperatures and pure W after stress relief annealed were comparatively assessed at 300~800°C via high temperature tensile testing machine,in terms of the effect of addition of rare earth oxide Y_(2)O_(3) on the mechanical properties of W-composites.It was found that with the increasing temperature,the tensile strength of W and W-Y_(2)O_(3)composites de-creased gradually,and the corresponding break elongation increased first and then decreased;while the tensile behavior of W and W-Y_(2)O_(3)composites all follow the ductile-brittle transition process,namely brittleness-pseudoplasticity-intrinsic plasticity.If tensile testing at the same temperature,W-Y_(2)O_(3)compos-ites exhibit better high plastic behavior than pure W.Whereas,W-Y_(2)O_(3)composites present the best plas-ticity and toughness at 600 C,with a break elongation even up to~46%.In addition,from the acquired ten-sile curves,it is found that the temperature at which pure W exhibits plastic behavior is near 400°C,while the temperature at which W-Y_(2)O_(3)exhibits plastic behavior is near 300°C.The constitutive equation of their strain hardening stage shows that pure W followed the power function strengthening behavior dominated by Hollomon's equation,while W-Y_(2)O_(3)shows logarithmic function strengthening behavior in the early stage of uniform plastic deformation,and the same power function strengthening behavior as that of pure W in the later stage of uniform plastic deformation.It follows that the addition of Y_(2)O_(3) can sig-nificantly enhance the plasticity and toughness of W composites,while reducing their brittleness and ductile-brittletransition temperature.
作者
陈昱溟
朱晓勇
谭晓月
刘家琴
吴玉程
CHEN Yuming;ZHU Xiaoyong;TAN Xiaoyue;LIU Jiaqin;WU Yucheng(School of Materials Science and Engineering,Hefei University of Technology,Hefei 230009,China;National-Local Joint Engineering Research Center of Nonferrous Metals and Processing Technology,Hefei University of Technology,Hefei 230009,China;National International Science and Technology Cooperation Base for Advanced Energy and Environmental Materials,Hefei University of Technology,Hefei 230009,China;College of Chemistry,Beijing University of Chemical Technology,Beijing 100029,China;Engineering Research Center of Advanced Composite Materials Design&Application of Anhui Province,Hefei230051,China)
出处
《材料研究学报》
北大核心
2025年第7期510-520,共11页
Chinese Journal of Materials Research
基金
国家自然科学基金国际(地区)交流与合作重点项目(52020105014)
国家自然科学基金面上资助项目(51474083,51672065)
国家重大研发计划磁约束核聚变重大专项(2022YFE03140001,2022YFE03140004,2019YFE03120002,2022YFE03030003)
国家“清洁能源新材料与技术”学科创新引智基地项目(B18018)。
关键词
金属基复合材料
弥散强化
高温拉伸
韧脆转变
metal matrix composites
dispersion strengthening
high temperature tensile
ductile-brittle transition
