采用专用管道式超临界水氧化（SCWO）反应腐蚀试验装置，研究了GH132高温合金管在25℃~520℃、27.2MPa的SCWO反应法处理航天推进剂废水工作环境中的腐蚀行为。结果表明：当T＞180℃时，试样发生晶间腐蚀（IGC），T＞260℃时，试样发生了浅点蚀，在280℃左右发生了径向贯穿试样的SCC，导致在试验151小时后试样失效。在340℃~370℃的均匀腐蚀速度最大，导致试样管壁减薄量超过100μm，当温度超过临界点后，试样管的腐蚀程度显著降低，只有轻微的浅点蚀。用EDX和IR分析腐蚀产物，发现亚临界温度段内试样中Fe、Cr、Ni的溶解和生成氧化物、氢氧化物，导致均匀腐蚀速度逐渐加快，而超临界温度段内腐蚀产物的溶解度降低，对基体表面的保护作用增强。GH 132高温合金管不能用作亚临界温度段内的连接管道。
Corrosion behavior of a candidate connecting tube, a GH132 tube, for supercritical water oxidation（SCWO）system in the environment of disposing the propellant wastewater by SCWO method with the range of temperatures from room temperature to 520℃ and the pressure of 27.2MPa was studied. The morphology of corrosion surface was analyzed using SEM. Intergranular corrosion (IGC) and shallow pitting occurred respectively when the temperature was above 180℃ and 260℃. Severe stress corrosion cracking was found at 280℃ which leaded to leak of the tube after 151h of testing. The maximum decrease in wall thickness of the tube was measured between 340℃ and 370℃,which amounted to 100μm. Within the supercritical temperature range, corrosion of the tube was obviously mitigated and only very shallow pits could be found. Corrosion products were analyzed using EDX and Fourier transfer infrared spectrometry (FTIR). The selective dissolution of elements such as Fe, Cr and Ni and the formation of corresponding oxides and hydroxides accelerated general corrosion within the subcritical temperature range; while, in the supercritical temperature range, corrosion products was protective due to their very low solubilities. Results showed that GH132 tubes could not be used as connecting tubes at subcritical temperatures.
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