• JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
 
  Bookmark and Share
 
 
Mémoire de Maîtrise
DOI
10.11606/D.18.2016.tde-02022016-090733
Document
Auteur
Nom complet
Aldo Braghini Junior
Unité de l'USP
Domain de Connaissance
Date de Soutenance
Editeur
São Carlos, 1998
Directeur
Jury
Coelho, Reginaldo Teixeira (Président)
Diniz, Anselmo Eduardo
Oliveira, João Fernando Gomes de
Titre en portugais
Investigação do desgaste de ferramentas de PCBN e metal duro no fresamento de topo de aços endurecidos
Mots-clés en portugais
Fresamento de topo
Metal duro
Metal endurecido
PCBN
Resumé en portugais
O fresamento de topo de aços ferramenta, no estado endurecido, pode ser uma alternativa para a fabricação de moldes e matrizes, com alta taxa de remoção. Este trabalho estuda os tipos e mecanismos de desgaste presentes nesta operação de usinagem, bem como o comportamento da emissão acústica. São realizados experimentos com ferramentas de PCBN e Metal Duro usinando os aços H13 (49-51 HRc), VMO (54-57 HRc) e VC131 (57-59 HRc). O desgaste das ferramentas de PCBN é significativamente menor que o desgaste das ferramentas de Metal Duro. O tipo de desgaste predominante é o desgaste de flanco, com indícios de desgastes de cratera. É observada uma combinação entre os mecanismos de desgaste abrasivo e adesivo. Não se observa a formação de trincas abaixo da superfície usinada. Verifica-se que a emissão acústica aumenta com a velocidade de corte e mostra-se também dependente do material da peça e da ferramenta.
Titre en anglais
not available
Mots-clés en anglais
Carbide
Endmilling
Hardened material
PCBN
Resumé en anglais
The endmilling operation applied to the machining of hardened tool steels, can be seen as an alternative to the conventional sequence of operations used in dies and injection moulds. Normally, eletrodischarge machining, which has a low removal rate, is applied for the finishing operation, just before polishing. The present research work study the types and mechanisms of wear that appear in this machining operation, as well as, the behaviour of Acoustic Emission (EA). Experiments are carried out using PCBN and Carbide tools, machining AISI H13 (49-51 HRc), AISI 6F3 (54-57 HRc) e AISI D6 (57-59 HRc). The wear observed on the PCBN tools was smaller than that on the carbide ones. The type of wear dominating was flank wear, with some presence of crater wear in a few machining conditions. It was also observed a combination between the abrasive and the adhesive mechanisms. It was not noted any cracks on the surface just below the machined surface. The acoustic emission showed to be directly proportional to the cutting speed and also dependent upon the workpiece material and to the tool material.
 
AVERTISSEMENT - Regarde ce document est soumise à votre acceptation des conditions d'utilisation suivantes:
Ce document est uniquement à des fins privées pour la recherche et l'enseignement. Reproduction à des fins commerciales est interdite. Cette droits couvrent l'ensemble des données sur ce document ainsi que son contenu. Toute utilisation ou de copie de ce document, en totalité ou en partie, doit inclure le nom de l'auteur.
Date de Publication
2016-02-02
 
AVERTISSEMENT: Apprenez ce que sont des œvres dérivées cliquant ici.
Tous droits de la thèse/dissertation appartiennent aux auteurs
CeTI-SC/STI
Bibliothèque Numérique de Thèses et Mémoires de l'USP. Copyright © 2001-2019. Tous droits réservés.