【摘要】 利用预敷硅粉氩弧堆焊方法,在纯钛基体表面制备出含有Ti5S i3相的堆焊层,在温度为800和900℃条件下对基体和堆焊层试样进行循环氧化试验.结果表明,不同组织堆焊层的高温抗氧化性能均比纯钛基体有明显提高.氧化试验温度低于钛的固态相变点时,堆焊层抗氧化性能按照亚共晶→共晶→过共晶的组织组成顺序提高.氧化试验温度为900℃时,三种组织组成的堆焊层的抗氧化性能与800℃时顺序相反,这主要是多次加热冷却导致相变应力积累,以及钛固溶体与Ti5S i3相的线膨胀系数不同引起热应力,堆焊层出现内部裂纹使氧化面积增加造成的.更多还原

【Abstract】 The surfacing layers with Ti5Si3 phase were prepared on the pure titanium substrate by argon arc-surfacing after pre-deposited with pure silicon powders.And the cyclic oxidation test was carried out at 800 ℃ and 900 ℃ for samples of the substrate and the surfacing layers.The test results showed that high temperature oxidation performance of the surfacing layers with different microstructures was obviously higher than that of the pure titanium substrate.When the oxidation test temperature is below the solid transformation point,the oxidation performance of the surfacing layers was improved in the order of hypoeutectic,eutectic and hypereutectic microstructures.But if the oxidation test temperature was 900 ℃,the order of the oxidation performance of the surfacing layers with three types of microstructures was inverse.The main reasons were that solid transformation stress was accumulated by repeatedly heating cooling and the thermal stress because of the difference of the linear expansion coefficients between titanium solid solution and Ti5Si3 phases,which resulted in internal cracks in the layers and large oxidized area.更多还原