Optimal maintenance policies during the post-warranty period for second-hand item

This paper studies the optimal periodic PM policies of a second-hand item following the expiration of warranty. The criterion used to determine the optimality of the PM is the expected maintenance cost rate per unit time from the customer's perspective. The periodic PM of the item starts right after the warranty is expired and all maintenance costs are paid by the customer. Given the cost structures of maintaining the item, we determine the optimal number of PM's before replacing the item by a new one and the optimal length of period for the periodic PM following the expiration of warranty.