EVALUATION METHOD FOR LUBRICATING FILM USED FOR PLASTIC WORKING, TEST PIECE EVALUATED WITH THE SAME, AND EVALUATION DEVICE FOR LUBRICATING FILM USED FOR PLASTIC WORKING

摘要

PROBLEM TO BE SOLVED: To provide an evaluation method for a lubricating film used for plastic working capable of showing an environment where the lubricating film is exposed at processing with a high degree of difficulty such as an object to be severely deformed, a test piece evaluated with the evaluation method for a lubricating film, and an evaluation device for a lubricating film used for plastic working.SOLUTION: Drawing work is performed by moving a holder 3a from an upper punch 1 side to a lower punch 2 side after finishing swaging work. When the holder 3a descends to the test piece 4', respective bearing section 3 moves downward along a side overhanged portion while respective bearing section 3 is pressed down to the side overhanged portion of the test piece 4' since the test piece 4' is already deformed at a barrel shape by the swaging work. Then, drawing work is applied to the test piece 4' by means of respective bearing section 3, and the side overhanged portion of the test piece 4' is deformed.