Improving the resistance to intergranular cracking and corrosion at elevated temperatures by grain-boundary-engineering-type processing
Improving the resistance to intergranular cracking and corrosion at elevated temperatures by grain-boundary-engineering-type processing
复制标题
通过晶界工程型加工提高高温下的抗晶间裂纹和腐蚀能力
DOI：
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发表时间：
2008
影响因子：
4.5
通讯作者：
U. Krupp
中科院分区：
文献类型：
--
作者：
U. Krupp
在高机械负载和/或侵蚀性环境下运行的结构部件的故障通常可归因于晶间降解，例如由于蠕变、腐蚀、疲劳或脆性开裂。本文重点关注氧扩散控制的晶界攻击，例如镍基高温合金的晶界攻击，该攻击会导致晶间氧化或动态脆化导致的快速裂纹。由于晶界扩散取决于相邻晶粒之间的晶体取向关系，因此采用晶界工程方法来降低对晶界攻击的敏感性。结合双晶裂纹实验的结果，从修改一般高角度和所谓特殊晶界网络的角度讨论了相关机制。
Failure of structural components operating under high mechanical loading and/or in aggressive environments can often be attributed to intergranular degradation, e.g. by creep, corrosion, fatigue or brittle cracking. The present article is focussed on oxygen-diffusion-controlled grain-boundary attack, for example, of a nickel-based superalloy leading to intercrystalline oxidation or rapid cracking by dynamic embrittlement. Since grain-boundary diffusion depends on the crystallographic orientation relationship between adjacent grains, the grain-boundary-engineering approach was applied to reduce the susceptibility to grain-boundary attack. The relevant mechanisms are discussed in terms of modifying the network of general high-angle and so-called special grain boundaries taking the results of cracking experiments on bicrystals into account.