Uticaj sistema površinske obrade Paulownia Siebold et Zucc. na mehanička svojstva lakirane površine

Abstract

U ovom radu ispitan je uticaj brušenja, operacije bajcovanja i primene poliuretanskog i akrilnog premaza na adheziju, otpornost na grebanje i otpornost na abraziju premaza. Cilj rada je bio određivanje najznačajnijih mehaničkih svojstava lakirane površine, sa stanovišta upotrebe Paulownia elongata i Paulownia fortunei, uz primenu različitih sistema površinske obrade drveta. Za ispitivanje adhezije premaza korišćen je metod rešetke. Obuhvatniji prikaz adhezije premaza dobijen je merenjem otpornosti na grebanje. Otpornost na abraziju je ispitana metodom slobodnog pada abrazivnih čestica. Primenjeni sistem brušenja nije imao uticaja na ispitivana mehanička svojstva. Bajcovani uzorci lakirani PU premazom pokazali su bolju adheziju u odnosu na nebajcovane uzorke. Uticaj bajcovanja na otpornost na grebanje nije utvrđen. Bajcovani uzorci pokazali su veću otpornost na abraziju kod obe drvne vrste. Više vrednosti mehaničkih svojstava pokazali su uzorci lakirani PU premazom u poređenju sa uzorcima lakiranim UV akrilnim premazom. Primena PU premaza za površinsku obradu Paulownia elongata i Paulownia fortunei je adekvatnija od primene UV akrilnog premaza, sa stanovišta otpornosti na grebanje i abraziju.

This paper presents the research of influence of sanding, staining and the use of polyurethane and acrylic coating on the adhesion, scratch resistance and abrasion resistance of the coating. Objective was to determine the most important mechanical properties of lacquered surfaces, considering the application of Paulownia elongata and Paulownia fortunei, by using different systems of surface finishing. Cross cut method was used for measurement of adhesion. More accurate view of coating adhesion was obtained by measuring the scratch resistance. Abrasion resistance was tested by the method of free falling of abrasive particles. The applied system of sanding had no effect on the examined mechanical properties. Stained samples lacquered with PU coating showed better adhesion to the non-stained samples. Impact of staining on scratch resistance is not established. Stained samples showed greater resistance to abrasion for both wood species. Samples lacquered with PU coating showed the higher values of mechanical properties compared with samples lacquered with UV acrylic coating. Application of PU coating for surface finishing of Paulownia elongata and Paulownia fortunei is more adequate than the application of UV acrylic coatings, from the point of scratch resistance and abrasion resistance.