ETD system

Electronic theses and dissertations repository

 

Tesi etd-01232020-005222


Thesis type
Tesi di laurea magistrale
Author
BOMBARDA, ILARIA
URN
etd-01232020-005222
Title
Development And Evaluation Of Tensile Testing For C/C-SiC Composite Materials
Struttura
INGEGNERIA CIVILE E INDUSTRIALE
Corso di studi
MATERIALS AND NANOTECHNOLOGY
Supervisors
relatore Lazzeri, Andrea
Parole chiave
  • Strain Gauges
  • Bending
  • Alignment
  • Tensile Test
  • Ceramics
  • Composite Materials
  • C/C-SiC
Data inizio appello
28/02/2020;
Consultabilità
Parziale
Data di rilascio
28/02/2090
Riassunto analitico
This thesis deals with de development of a system to perform tensile tests on CMC C/C-SiC materi-als. The motivation behind this attempt is to investigate Weibull’s analysis and the peculiarity that this theory presents in CMC materials. The main problem in tensile testing of CMC materials is to combine a good gripping and a perfect alignment. This difficulty is driven in particular by the rough surface of the specimen and by the stiffness of CMC materials. The work is divided into 4 main top-ics: the choice of the specimen design and shape, the design of the gripping system, the design of the connection between the gripping system and the testing device and the strain gauge verification procedure. The gripping system has been projected in order to compensate the specimen’s roughness, with a system of self-alignment provided by two sliding pins and a carriage, together with two brass inserts. During the test, tension force is transferred through specimen shoulders. The connection between the gripping system and the testing device is based on the insertion of a swivel head, to minimize bending and torque forces. Ten plates in CFRP state are prepared starting from pre-treated carbon fabrics and PEEK powder, all of them with the same thickness and fiber volume content. The plates are then pyrolyzed in two steps and siliconized via LSI. The plates are cut with EDM to obtain 240 specimens in two different widths. To understand whether if the alignment is reached or not, before testing the specimens, strain gauges verification procedure is performed.
File