| Superplasticity is the general potential property of materials of lattice structure. It's a process that materials establish a stable deformation course after they are deformed and become unstable. It's mostly a boundary behavior, i.e. boundary gliding, transferring and shifting occurred as a microcosmic physical behavior. Realization of superplasticity is the result of harmonization between intrinsic and extrinsic qualification of material. Ceramic, intermetallic compounds, and alloys of aluminium and lithium et al, are all advanced materials of superplasticity。Intermetallic compounds are formed by tantalum and metalloid, its atoms are arranged in the form of big length and high order, and its metal bonds and covalent bonds are coexisting. Therefore, it has not only the better plasticity of metal but also the intension of ceramic under high temperature. Intermetallic compounds are important constructional materials for industry such as aviation, 超塑性aceflight, traffic, chem. , mechanism et al, also they are functional meterials for semiconductor, magnetism, hydrogen storing, superconductor et al, because of their low-density, high-melting point, and the property between metals and ceramic.The basic characteristic of intermetallic compound as a constructional material is its high 超塑性ecific intension under room temperature, and the ca capability of be maintained under high temperature. During the last few decades, American, Japan, and other Europe countries advanced in industry have all established nationally research projects to develop intermetallic compounds. hey have all attached importance to developing a constructional materials under high temperature that is intervenient between Ni-based alloys and ceramic under high temperature, aiming at filling in the inter超塑性ace between Ni-based alloys and ceramic under high temperature on temperature and mechanical property.Intermetallic compound has generally a problem that it is brittle which leads to a poor capability to be machined. Shaping by superplasticity offers it a feasible way for machining. My thesis aims at offering a prophase work for the following study on superplasticity of intermetallic compound, which stretches and extends fields of superplasticity on hard and brittle materials.Intermetallic compounds are composed of compounds of aluminium and silicon, and intermetallic compounds hard to be melted, and the study throughout international is focused on the former two. Compounds of aluminium include Ni-Al, Ti-Al and Fe-Al et al, compounds of silicon include Mo-Si,Fe-Si and Ni-Si et al. As constructional materials , intermetallic compounds have following basic mechanical properties: 1) yielding intension increases with temperature elevating, as called phenomena R; 2) brittleness—intrinsic brittleness and environment embrittlement. The problem of brittleness is the most important infection that influences the developing tends towards practicality. Contrasting with compounds of silicon, the Crystal structure of compounds of aluminium is more simple and more symmetrical, besides, it has less sever brittleness. From these points, compounds of aluminium are the primary applied materials. System Ni-Al has two compounds of Ll2-type Ni3Al and B2-type NiAl. Ni3Al- based alloy has high-melting point and good ability of oxidation resisting. Between certain temperatures, Ni3Al- based alloy has the characteristic called phenomena R. Ni3Al- based alloy studied currently has ollowing composition as Ni-14/18Al-6/0Cr- 1/4Mo- 0.1/1.5Zr or Hf-0.01/0.02B (atom percent, %). Ni3Al- based alloy can be made by fuse melt or powder metallurgy. Alloys developed by Ni3Al are IC-50,IC-218, IC-221M and MX-246 et al. The academe of aviation material of Peking in our country has also developed Ni3Al- based alloy IC-6 independently。Ni3Al- based alloy can be applied for engine firebox of turbine and supercharger of diesel engine.NiAl- based alloy has high-melting point , low-density, good ability of oxidation resisting, high-conductivity , big E value, and has an an...
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