Erosion Rate Testing at High Temperature of Alloys and Coatings for Use in Turbomachinery

Abstract

Because of the serious consequences of turbomachinery erosion on their performance and life, it is important to have reliable methods for predicting their erosion when solid particles are ingested with the incoming flow. This is a very challenging problem since turbomachinery erosion is affected by many factors such as blade passage geometry, blade row location, rotational speed flow conditions, blade material and particles’ characteristics. Several studies which are essential to predicting blade surface erosion intensity and pattern, have been conducted at the University of Cincinnati’s Propulsion Laboratory over the past twenty-five years. This paper describes only some of the work done on erosion testing at high temperatures and velocities for different materials and coatings. The testing has been performed with a special high temperature erosion wind tunnel which simulates the aerodynamic conditions on the blades. The coated substrates reveal one order of magnitude less wear compared to some commercial non-CVD coatings on the same alloys. This study demonstrates that some coatings provide an excellent erosion resistance to INCO 718, LNCO 738, MAR-246, X-40 and Tungsten Carbide.

Study of solid particle impact effects and coating thickness on the erosion damage

“…Since there are three parameters and each parameter in two levels based on two-level factorial designs, 2 3 simulations are carried out in this paper, and the results including erosion depth and erosion volume are listed in Table 1.…”

“…1 The performance of erosion resistant coatings is usually established experimentally through the measurement of the minimum erosion loss. 2,3 Many researchers have attempted to calculate erosion rate (ER) of coatings. As a result, many difficulties were encountered when erosion tests were performed to measure ER of coatings, frequently relevant to the interactions of many factors influencing the erosion phenomenon.…”

Solid particle erosion mechanisms of protective coatings for aerospace applications

“…In particular, the group of Tabakoff have evaluated many different coatings found in aerospace applications (Pt-Al, Rd-Pt-Al, CrC, NiCrC, Cr, WC-Co, TiC, TiN, Al 2 O 3 and CVD diamond) in a specially constructed high temperature erosion test rig that simulates, as closely as possible, the particle impact conditions found in the engine [5,121,128,[138][139][140][141][142][143][144][145][146][147][148][149][150][151]. Although most of their studies were comparative, they have shown that in many cases the increased ductility at high temperature is beneficial for erosion resistance of hard coatings.…”