Abnormal Wear Analysis of Wear-resistant White Cast Iron Needle Ring for Loom

During the product testing of textile machinery parts, it was found that the needle ring had rapid wear at the contact position with the needle piece before it reached the expected design life. To find out the wear cause, a severely worn needle ring and an unworn needle ring after long time testing were analyzed. Macro observation, composition analysis, hardness testing, micro metallography, SEM observation and EDS analysis were carried out. It is found that the wear of the needle ring belongs to abrasive wear. The reason for the abrasive wear is that the carbides are distributed in a network of large particles and long strips, and the small number of secondary carbides in martensite reduces the inclusion and support ability of martensite matrix to eutectic carbides. As a result, the eutectic carbides distributed in blocks are easy to peel off from martensitic matrix to form abrasive particles, finally resulting in abnormal wear.