Microscope images of the coating surface of Material #1 drawn over 5T die radius are shown in Fig. 7(a–c). It can be seen that under the 100% oil lubrication condition, the coating surface appears glossier with less obvious scratch than the surfaces formed under other two lubrication conditions. It should also be noted that the scratch mark in Fig. 7(a) could be caused by the high friction observed in the beginning of the test.