检索结果-南通市图书馆

reciprocating extrusion OF IN SITU Mg_2Si REINFORCED Mg-Al BASED COMPOSITE

Acta Metallurgica Sinica(English Letters) 2008年第3期21卷 169-177页

作者： Z.M. Zhang C.J. Xu X.F. Guo S.Z. Jia School of Materials Science ＆ Engineering Xi＇an University of Technology Xi＇an 710048 China

M92Si reinforced Mg-Al based composite with high amount o/silicon was prepared by permanent mould casting, and then extruded by reciprocating extrusion （RE） after the composite was processed by homogenization heat treatment. The effect of RE processing on the morphology and size of M92Si and the mechanical properties of the com- posite were investigated, to develop new ways to refine the M928i phase and improve its shape. The result showed that RE was very useful in refining the M92Si phase. The more the RE processing passes, the better the refining effect would be. Moreover, the uniform distribution of M928i phases would be more in the composite. After the composite was processed by RE for 12 passes, most M92Si phases were equiaxed, with granular diameter below 20 μm, and distributed uniformly in the matrix of the composite. The mechanical properties of the composite could be increased prominently by RE processing, and were much higher than that in the as-cast state. As the temperature rises, the tensile strength is reduced. For the composite RE processed for 12 passes, the tensile strength, yield strength, and elongation are 325.9 MPa, 211.4 MPa, and 3.3% at room temperature, whereas, 288.2 MPa, ,207.7 MPa, and 7.8%, respectively, at 150℃. In comparison with the properties at room temperature, the tensile strength and yield strength are high and only decrease by 11.6% and 1.8% at 150℃. The M928i reinforced Mg-Al based composite possesses good heat resistance at 150℃. The excellent resistance to effect of heat is attributed to the high melting tempera- ture and good thermal stability of fine Mg2Si phases, which are distributed uniformly in the composite, and effectively hinder the grain boundary gliding and dislocation movement.

关键词： reciprocating extrusion Magnesium alloy In situ composite Elevated temperature property

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

MICROSTRUCTURE OF Mg-6.4Zn-1.1Y ALLOY FABRICATED BY RAPID SOLIDIFICATION AND reciprocating extrusion

引用

Acta Metallurgica Sinica(English Letters) 2008年第1期21卷 30-36页

作者： Z.M. Zhang C.J. Xu X.F. Guo School of Materials Science ＆ Engineering Xi＇an University of Technology Xi＇an 710048 China

In order to explore the methods to prepare high-strength quasicrystal-reinforced magnesium alloys, the flakes of rapidly solidified Mg-6.4Zn-1.1 Y magnesium alloy with a thickness of 50-60μm were obtained by a melt spinning single-roller device, and the flakes were then processed into rods by reciprocating extrusion and direct extrusion. The microstructure of the alloy was analyzed by optical microscope and SEM, and the constituent phases were identified by XRD. Phase transformation and its onset temperature were determined by differential thermal analyzer （DTA）. The analysis result shows that rapid solidification for *** alloy can inhibit the eutectic reactions, broaden the solid solubility of Zn in α-Mg solute solution, and impede the formation of Mg3 Y2Zn3 and MgZn2 compounds, and thus help the icosahedral Mg3 YZn6 quasicrystal formed directly from the melt. The microstructure of the flakes consists of the α-Mg solid solution and icosahedral Mg3 YZn6 quasicrystal. Dense rods can be made from the flakes by two-pass reciprocating extrusion and direct extrusion. The interfaces between flakes in the rods can be welded and jointed perfectly. During the reciprocating extrusion and direct extrusion process, more Mg3 YZn6 compounds are precipitated and distributed uniformly, whereas the rods possess fine microstructures inherited from rapidly solidified flakes. The rods contain only two phases： α- magnesium solid solution as matrix and fine icosahedral Mg3 YZn6 quasicrystal which disperses uniformly in the matrix.

关键词： Magnesium alloy Rapid solidification reciprocating extrusion Quasicrystal

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

MICROSTRUCTURES AND PROPERTIES OF reciprocatingLY EXTRUDED Mg-6.4Zn-1.1Y ALLOYS

引用

Acta Metallurgica Sinica(English Letters) 2008年第1期21卷 37-42页

作者： Z.M. Zhang C.J. Xu X.F. Guo School of Materials Science ＆ Engineering Xi＇an University of Technology Xi＇an 710048 China

An icosahedral Mg3 YZn6 quasicrystalline phase can be produced in Mg-Zn- Y system alloys when a proper amount of Zn and Y is contained, and it is feasible to prepare the quasicrystal phase-reinforced low-density magnesium alloy. In this article, phase constituents and the effect of reciprocating extrusion on microstructures and properties of the as-cast Mg-6.4Zn-1.1 Y alloy are analyzed. The microstructure of the as-cast Mg-6.4Zn-1.1 Y alloy consists of the α-Mg solid solution, icosahedral Mg3YZn6 quasicrystal, and Mg3 Y2Zn3 and MgZn2 compounds. After the alloy was reciprocatingly extruded for four passes, grains were refined, Mg3 Y2 Zn3 and MgZn2 phases dissolved into the matrix, whereas, Mg3 YZn6 precipitated and distributed uniformly. The alloy possesses the best performance at this state; the tensile strength, yield strength, and elongation are 323.4 MPa, 258.2 MPa, and 19.7%, respectively. In comparison with that of the as-cast alloy, the tensile strength, yield strength, and elongation of the reciprocatingly extruded alloy increase by 258.3%, 397.5%, and 18 times, respectively. It is concluded that reciprocating extrusion can substantially improve the properties of the as-cast Mg-6.4Zn-1.1 Y alloy, particularly for elongation. The high performance of the Mg-6.4Zn-1.1 Y alloy after reciprocating extrusion can be attributed to dispersion strengthening and grain-refined microstructures.

关键词： reciprocating extrusion Mg-Zn- Y alloy Icosahedral quasicrystal

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Superplastic Behavior of reciprocating Extruded Mg-6Zn-1Y-0.6Ce-0.6Zr from Rapidly Solidified Ribbons

引用

Journal of Wuhan University of Technology(Materials Science) 2012年第6期27卷 1033-1037页

作者：郭学锋 YANG Wenpeng REN Fang School of Materials Science and Engineering Henan Polytechnic UniversityJiaozuo 454000China School of Materials Science and Engineering Xi'an University of TechnologyXi'an 71004&China School of Economics and Management Henan Polytechnic UniversityJiaozuo 454000China

RRE-Mg66 alloy with a composition of Mg-6.0%Zn-1.0%Y-0.6%Ce-0.6Zr was prepared by combinatorial processes of rapid solidification, reciprocating extrusion and extrusion. Microstructure was evaluated on SEM and TEM. The average grain size of the alloy is 0.7 μm, the size of the second phase at grain boundary is 0.15 μm, and the size of the intragranular precipitates in round shape is less than 20 nm, Superplastic behavior of the material was investigated in a temperature range of 150 to 250 ℃ and initial strain rate range of 3.3×10^-4 to 3.3 × 10^-2 s^-1 in air. The highest elongation of 270% was obtained at 250 ℃ and 3.3 × 10^-3 s-L High-strain-rate superplasticity and low-temperature superplasticity were achieved. The superplasticity results from intragranular sliding （IGS） at temperatures from 170 to 〈 200 ℃ and grain boundaries sliding （GBS） at 250 ℃. At 200 ℃ a combination of IGS and GBS contributes to the superplastic flow.

关键词： rapid solidification reciprocating extrusion extrusion superplasticity

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：