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Martensite stainless steel (MSS) possesses excellent strength and medium corrosion resistance, and is often used in industrial applications, such as for highly stressed parts like turbine blades and pipe materials. However parts are often damaged by flow field particles interact with the materials, in a solid particle erosion (SPE) phenomenon, which may even lead to injuries. In this paper we discuss the effects of the tempering treatment and the erosion incident angle on the CA-15 MSS erosion behavior. The results show that, in single particle erosion tests, the main mechanisms that cause problems are micro-cutting and deformation craters at low and high incident angles, respectively. In repetitive particle erosion tests, grain boundary cracking is one of the main fracture mechanisms. The platelet mechanism also obvious affected at high incident angle erosion. Materials tempered at 573-673 K, tempered martensitic embrittlement (TME) occurred, which caused serious boundary cracking and grain broken-down. The serious erosion damage showed at medium incident angle for this material that result in combine of cutting, deformation crater, and cracking mechanism. The maximum erosion rate of material occurred at an incident angle of =6 and the deepest erosion penetration occurred at an incident angle of =4.

This research studied the possibility of non-destructive detection of temper-embrittlement in tempered CA-15 martensitic stainless steel (MSS). It was found that secondary hardening phenomenon existed in tempering temperature range of 573-673 K for the MSS in this study. Ultrasonic responses, both in terms of acoustic velocity and attenuation, exhibited changes with respective to the microstructure variation. Microstructural constituent of chromium carbide (Cr 23 C 6 type) precipitates was found to have resulted in the temper-embrittlement of the MSS and also was responsible for the changes of the ultrasonic behavior of the material.

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