Avaliação de desgaste por perda de massa de sistema extrator de moldes de injeção de termoplásticos revestidos com filme fino de DLC

This paper has as objective, the deposition of DLC thin films over components of injection mold extractor system, checking the influence of this surface coating in the wear of these components, under different surface lubrication configurations. For this evaluation, extractor pins, currently produced in steel AISI H13, by gas nitriding, was coated with DLC (Diamond Like Carbon) thin films. The DLC thin film has been deposited in a chamber with system PECVD (Plasma Enhanced Chemical Vapor Deposition). A device that simulates of the extraction system of an injection mold was used to test the wear behavior of sets pin-bushing proposed, in function of increased number of cycles. Pin wear was quantitatively assessed by mass loss after 100,000 cycles. The results of mass loss show that for samples without using grease, the wear rate was considerably lower. The pins that showed less wear were PS and HS sets, both without using grease, with a loss of 5.400 and 5.467 mg, respectively. Whit this, was evidenced the possibility of using DLC coated pins without use of grease in injection mold extraction systems and that this still provided a considerable reduction in the wear rate.