论文部分内容阅读
本文用电化学方法测定了 IN-738和 FSX-414燃气涡轮合金在1,100°K(827℃)碱金属熔螎硫酸盐(1大气压-101千牛顿/米~2氧和1.95×10~(-4)大气压-19.8牛顿/米~2SO_3)中的腐蚀速率,试验周期达2,500小时。观察到最初腐蚀速率下降,由此假设形成了保护膜,接着由于保护膜的破坏而腐蚀速率增加。腐蚀试样的显微镜检查发现在紧靠氧化层之下的硫化物相沿晶界渗透到基体金属中去。除了金属腐蚀外,考虑了氧化反应对腐蚀电流测定的影响。在某些条件下,腐蚀电位接近熔融物中氧化还原电位,而熔融硫酸盐中氧化反应对表现腐蚀电流产生显著影响。本文也描述了对这个效应的修正。
In this paper, electrochemical measurements of the corrosion rate of IN-738 and FSX-414 gas turbine alloys were carried out at 1,100 ° K (827 ° C) for 1 s-10 1 kN / m 2 and 1.95 × 10 ~ 4) Atmospheric pressure -19.8 N / m ~ 2SO_3), the test period is 2,500 hours. A decrease in the initial corrosion rate was observed, thereby assuming that a protective film was formed, followed by an increased corrosion rate due to the destruction of the protective film. Microscopic examination of the corroded specimen revealed that the sulfide phase immediately beneath the oxide layer infiltrated into the base metal along the grain boundaries. In addition to the metal corrosion, the effect of the oxidation reaction on the corrosion current is taken into account. Under certain conditions, the corrosion potential approaches the redox potential of the melt, whereas the oxidation reaction in molten sulphate has a significant effect on the corrosion current. This article also describes the correction of this effect.