Author: H. T. QuiggPublisher:
ISBN:
Category :
Languages : en
Pages : 173
Book Description
An experimental investigation was conducted to determine whether the maximum sulfur content of 0.40 weight per cent, currently allowed in grade JP-5 aviation turbine fuel, is a safe level for the protection of turbine blade alloys used in high-performance engines. Four nickel-base alloys (Udimet 500, Inco 713C, IN-100 and SM-200), one cobalt-base alloy (WI-52 and one aluminum-diffusion coated alloy (Misco MDC-1 on Inco 713C) were exposed to vitiated air in Phillips hot corrosion test rig at high pressure (15 atmospheres) and high velocity (565 to 805 ft/sec) during a five hour cyclic test. A statistically designed program was used to evaluate the effect of temperature (1400, 1600, 1800, 2000 and 2200 F), fuel sulfur (0.0002, 0.040 and 0.40 weight per cent) and sea salt in air (zero, 1.0 and 10.0 ppm). The significance of metal weight loss by test specimens was determined by analysis of variance, made at a confidence level of 95 per cent. The validity of metal weight loss data was established by metallographic examination of test specimens, which showed a correlation with depth of penetration and the absence of deep intercrystalline attack.
