Fosfat bağlı revetmanlardaki genleşmelerin dökümlerin kenar uyumlarına etkisinin incelenmesi

Abstract

Bu <;ah~mada, ii<; genle~me teknigini degerlendinnek i<;in ii<; farkh fosfat baghrevetman kullamlrm~nr. Bu ama<;la, dik ve geni~ a<;1h metal giidiikler haZirlanml~ vebunlann iizerinde mum kuron ornekler elde edilmi~tir. Mum ornekler metal man~etli vemetal man~etsiz olarak revetmana almrm~nr.Higroskopik genle~me yontemi ile termal genle~me yontemi arasmda bir farkolmad!gl, sertle~me genle~mesinin bu iki tip genle~meden daha az oldugu istatistikselolarak saptanrm~nr. Diger tan!ftan higroskopik genle~me teknigi ile yap1lan dokiimlerin,1~1k mikroskobunda elde edilen fotograflannda marjinal aral1gm geni~liginin daha azolmas1,bu yontemin doktim i~lemlerinde daha giivenilir oldugunu gostermi~tir.Buna ilaveten, ii<; farkh fosfat bagh revetmanm mrujinal uyumlan arasmda onemli birfark bulunmadljp., metal man~et kullan!larak yap!lan dokiimlerde mrujinal aral1jp.n daha azoldugu, dik a<;1h giidiikten elde edilen kuron orneklerinde mrujinal adaptasyonun daha iyioldugu istatistiksel olarak tesbit edilmi~tir.

In the present study, three expantion techniques were compared by using threedifferent phosphate bonded investment. For this purpose, metal dies with right and wideangle were prepared, and wax crown patterns were modelled upon them. The waxpatterns were immersed into the investments with and without metal ring.It has been found that there is no statistically significant difference between thehygroscopic and termal expantion methods, and that the setting expantion rate is less thanthose of the other methods. On the other hand, it has been observed from the photographstaken by ligth microscope that the widths of the marginal spaces are less. At the samplesobtained by hygroscopic expantion technique according to these results, the hygroscopicexpantion technique is the most reliable method in casting procedures.In addition, it has been statistically found that there is no significant differencebetween the marginal adaptation of the three different phosphate bonded investments, andthat the marginal spaces are less in castings used metal rings, and also that the marginaladaptations are better at the crown patterns obtained from the dies with right angle.