Study on improvement of high temperature strength in oxidation environment of intermetallic compound and Nickel-base superalloys by electric-discharge anti-oxidation surface treatment

放电抗氧化表面处理提高金属间化合物及镍基高温合金氧化环境下高温强度的研究

• 批准号: 04650097
• 负责人: IINO Yutaka
• 金额: $ 1.34万
• 依托单位: Toyota Technological Institute
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1992
• 资助国家: 日本
• 起止时间: 1992 至 1993
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-04650097/
• 关键词: high temperature oxidation; intermetallic compound; Ni-base superalloy; electric-discharge-machining; surface modification; low cycle fatigue; creep; 金属間化合物

To improve both oxidation resistance and mechanical properties such as low cycle fatigue crack initiation life and creep crack initiation time of stress concentration part, electric-discharge surface modification technique was used, by which intermetallic compound TiAl and Nickel-base superalloys 713LC and 738LC were electric-discharged using NiCrAlY electrode. Oxidation test, high temperature low cycle fatigue test and creep test were carried out. The modified surface of TiAl have many microcracks and the the surface-modification test was interruptted. Oxidation resistance of 713LC and 738LC in ranged 900-1000ﾟC was improved significantly by this technique. Low cycle fatigue crack initiation life at 800ﾟC of 738LC notched compact tension specimen was comparable with non-treated one. Creep crack initiation time at 900ﾟC of the CT specimen was improved with less oxidation, while the oxide film of the non-treated one spalled much.

为了提高应力集中部位的抗氧化性和低周疲劳裂纹萌生寿命、蠕变裂纹萌生时间等力学性能，采用电火花表面改性技术，对金属间化合物TiAl和镍基高温合金713LC和738LC进行NiCrAlY电极放电处理。进行了氧化试验、高温低周疲劳试验和蠕变试验。TiAl表面有许多微裂纹，表面改性试验中断。该技术显著提高了713LC和738LC在900-1000ﾟC温度范围内的抗氧化性。738LC缺口紧凑拉伸试件在800ﾟC下的低周疲劳裂纹萌生寿命与未处理试件相当。随着氧化程度的降低，CT试件在900ﾟC的蠕变裂纹萌生时间延长，而未处理的试件氧化膜剥落较多。