中文摘要：

通过失重腐蚀试验和应力腐蚀开裂（四点弯曲法）试验,研究了TC4钛合金在地层水和完井液环境中抗均匀腐蚀、局部腐蚀和SCC性能。结果表明：在地层水CO2腐蚀环境中,TC4钛合金为轻微腐蚀,温度升高,均匀腐蚀速率变化不大,温度达到220℃时,均匀腐蚀速率仅为0.0012 mm/a,且试样表面无局部腐蚀,表明该合金具有良好的抗地层水CO2均匀腐蚀和局部腐蚀性能;在完井液CO2腐蚀环境中,TC4钛合金的均匀腐蚀速率高达0.4247mm/a,该合金发生明显的点蚀和选择性溶解腐蚀;在地层水CO2腐蚀和完井液CO2腐蚀环境中SCC试验均未发现裂纹,具有良好的抗SCC性能。

英文摘要：

The corrosion behaviours of TC4 titanium alloy in the formation water and the completion fluid corrosion environment were studied by mass loss and stress corrosion cracking（four-point bent test）. The results show that TC4 titanium alloy has slight corrosion in formation water corrosion environment with CO2. With temperature increasing, the corrosion rate of TC4 titanium alloy changes little.The corrosion rate is 0.0012 mm/a when the temperature is 220 ℃. And the localized corrosion morphology on samples surface could not be observed, which can prove that TC4 titanium alloy has good resistance to uniform corrosion and localized corrosion in formation water corrosion environment with CO2. In the completion fluid corrosion environment with CO2, the uniform corrosion rate of TC4 titanium alloy is up to 0.4247 mm/a, and TC4 titanium alloy generates obvious pitting corrosion and selective dissolution corrosion. In the SCC test, no cracks are found on the surface of the test specimen, and then, TC4 titanium alloy has good resistance performance to SCC.