Hojat Ahmadi
材料科学技术（英）
TiNi alloy has a high resistance to wear and could be an excellent candidate for various tribological applications. In this paper, it was demonstrated that by addition of yttrium, hardness properties and resistance to wear and corrosive wear of TiNi alloy were improved. New yttrium rich regions were formed in microstructure of TiNi alloy. The improved properties of this alloy by the yttrium addition could be attributed to the formation of these regions. The results showed that there was an optimum content for addition of yttrium between 2% and 5% (in wt%), and above this content the improvement in properties of TiNi became minor.
关键词:
Yttrium
Hojat Ahmadi
材料科学技术（英）
TiNi alloy has a high resistance to wear and could be an excellent candidate for various tribological applications. In this paper, it was demonstrated that by addition of yttrium, hardness properties and resistance to wear and corrosive wear of TiNi alloy were improved. New yttrium rich regions were formed in microstructure of TiNi alloy. The improved properties of this alloy by the yttrium addition could be attributed to the formation of these regions. The results showed that there was an optimum content for addition of yttrium between 2% and 5% (in wt%), and above this content the improvement in properties of TiNi became minor.
关键词:
Yttrium
Zheng LIU
金属学报(英文版)
Semi-solid Al7Si0.3Mg alloy slurry, which is grain-refined by yttrium, is manufactured by low temperature pouring. The effects of grain-refined by yttrium on the morphology and the grain size of the primary α-Al in semi-solid Al7Si0.3Mg alloy are researched. The results indicate that semi-solid Al7Si0.3Mg alloy with particle-like and rosette-like primary α-Al can be prepared by low temperature pouring from liquid Al7Si0.3Mg alloy grain-refined by yttrium. The grain size and particle morphology of primary α-Al in Al7Si0.3Mg alloy are markedly improved by 0.5 wt pct Y. The refining mechanism of Y on the morphology and the grain size of the primary $\alpha$-Al in semi-solid Al7Si0.3Mg alloy are delved.
关键词:
Semi-solid
,
钇
,
Al7Si0.3Mg合金
,
细化机制
LI Bei WU Shuangxia LI Dianchen Baotou Research Institute of Rare Earth Ministry of Metallurgical Industry
,
Baotou
,
ChinaMA Ruzhang University Science and Technology Beijing
,
Beijing
,
China Baotou Research Institute of Rare Earth
,
Ministry of Metallurgical Industry
,
Baotou 014010
,
China
金属学报(英文版)
A high temperature embrittlement occures in Fe-15Cr-4AI and Fe-20Cr-4Al alloys treated over 1000 C.It is caused mainly by 475℃ brittleness during cooling.When a secondary treatment at 500℃ was conducted,the 475℃ brittleness developed very rapidly.After only 15 rain of the treating,little plasticity was remained for all samples pretreuted at the temper- atures over 1000℃ and cooled in water.However,no 475℃ brittleness was generated when pretreating temperature was below 1000℃,Addition of Yttrium can inhibit not only grain growth,but also 475℃ brittleness.For the alloys with 0.2—0.4 wt-%Y,after treating at 800—1300℃,the plasticity did not decrease and the properties of furnace cooled samples were not lower than those of water cooled samples.
关键词:
Fe-Cr-Al alloy
,
null
,
null
韩钰
,
夏延秋
,
祝志祥
,
孙远
,
宾杰
,
李红英
,
杨长龙
材料科学与工艺
doi:10.11951/j.issn.1005-0299.20160512
随着特高压输电技术在我国的大力发展，铝合金导体材料作为特高压输电线路的主要组成部分，受到业内的广泛关注．本文采用电导率测试、硬度测试、金相显微镜和扫描电镜观察等手段，研究添加不同含量稀土Y对铸态Al－Zr耐热铝导体材料的影响．研究结果表明：Y元素和Fe、Si等杂质元素形成金属间化合物，可净化基体，改变杂质相的形态和分布，使其粒子化、球化和细化．Y元素在枝晶网络和晶界分布，从而细化晶粒和枝晶组织，但添加量达到0．5％时晶粒细化不均匀．当Y含量为0．2％时，电导率达到60％IACS；当Y含量为0．3％时，硬度达到最高值20．9HBS，且电导率并无明显下降．加入0．3％ Y可使耐热铝导体材料获得较好的综合性能．
关键词:
Y
,
铝导体
,
晶粒细化
,
电导率
,
硬度
