Because the SmCo magnets contained iron components, so SmCo magnets will also rust. But compared with NdFeB magnets, the iron content is relatively low, therefore, rust phenomenon is not very serious for SmCo magnets. If put the SmCo magnets in the seawater, the surface will produce some rust, but does not affect its performance and use. Therefore, usualy SmCo magnet does not require electroplating.