Effect of Mo content on erosive wear characteristics of high chromium cast iron at 1173 K

• Published in: Wear 2017-04, Vol.376-377, p.542-548
• Main Authors: Shimizu, Kazumichi, Kusumoto, Kenta, Yaer, Xinba, Zhang, Yao, Shirai, Masato
• Format: Article
• Language: English
• Subjects: Aluminum oxide; Carbides; Cast iron; Chromium; Crystallization; Hardenability; Hardness; High temperature; Iron; Melting points; Molybdenum; Soil erosion; Wear
• ISSN: 0043-1648; 1873-2577
• DOI: 10.1016/j.wear.2016.12.030

Crystallization of carbides with high hardness in the matrix was proved to be effective to improve erosive wear characteristics under high temperature conditions. In the present study, molybdenum (Mo) with the ability to increase hardenability was added into high chromium cast iron. Erosive wear characteristics of six kinds of materials with 16, 26 mass % chromium (Cr) and 0, 1, 3 mass % Mo content was investigated at 1173 K, using alumina balls with size of 1.16 mm at velocity of 30 m/s. As results, 16Cr–3Mo and 26Cr–3Mo showed the best erosive wear characteristics at 1173 K, which has been improved for about 36% compared to material 16Cr and 28% compared to material 26Cr. With the increasing of Mo addition, the reduction of M7C3 carbides’ hardness was suppressed. The existence of M2C carbides with high hardness and melting point was also considered to be another important factor to improve erosive wear characteristics. Therefore, with the feature of increasing the hardness of M7C3 carbides and promoting the formation of M2C carbides with high hardness and melting point, Mo was proved to be effective in improving the erosive wear characteristics of high chromium cast iron at 1173 K. Furthermore, since 16Cr–3Mo and 26Cr–3Mo showed the erosive wear characteristics at the same high level, it is possible to save costs significantly by cutting Cr addition from 26 mass % to 16 mass %.