TALLINNA TEHNIKAKÕRGKOOL TALLINN COLLEGE OF ENGINEERING KIUDTUGEVDATUD KOMPOSIITMATERJALID REFERAAT Õppeaines: Tehnomaterjalid I Juhendaja: D. Arensburger Mehaanika teaduskond Õpperühm: MI- 21 Tallinn 2009 MATERJALI OMADUSED SURVEL Õhukeste komposiitlaminaatide survetaluvuse omadusi on suhteliselt raske mõõta tänu proovidetaili külgpidisele rabedusele. On proovitud mitmeid testimismeetodeid ja mitmeid proovidetaili kujusid, et vältida esilekerkivat probleemi. Siinkohal kirjeldaks neist meetoditest kolme. Celanese test: see test on võetud kui standartne surve test ja seda on detailselt kirjeldatud ASTM D3410-87 standardis. Testi põhimõte seisnes sellest et võetakse sirge proovidetail, mille otsetesse kinnitatakse labad. Seejärel asetatakse see koonilise kujuga silindri sisse, mis omakorda sobitatakse täpselt teise vormi sisse mille siseserv...
kasutatav matemaatiline mudel tuleneb Boltzmanni printsiibist ja omab järgnevat kuju: = 0J(t t0) + (1 0)J(t t1) +...+ (i i-1)J(t ti)+..., kus J on materjali vastavus ehk J= 1/E. Boltzmanni printsiip kehtib nii väga väikeste deformatsioonide puhul kui ka suurte deformatsioonide puhul, mis on kaua kestvad. See on tingitud sellest, et polümeersetel vedelikel on kahanev mälu mineviku koormuste suhtes. Kasutatud kirjandus 1. http://www.me.umn.edu/labs/composites/Projects/Polymer%20Heat%20Exchanger/Creep %20description.pdf (26.03.2012) 2. Montgomery T. Shaw, William J. MacKnight, ,,Introduction To Polymer Viscoelasticity", kättasaadav: http://books.google.ee/books? id=HS7wp0QiISkC&pg=PA27&lpg=PA27&dq=boltzmann+superposition+principle&sourc e=bl&ots=nwK9l5kCPh&sig=ADBBXBmD8IWqibd4EPfQBFG9EsU&hl=et&sa=X&ei=hs OnT4CTJZDR4QStrdzSCA&ved=0CGcQ6AEwBQ#v=onepage&q=boltzmann
strings. For the first century of the modern game, racquets were of wood and of standard size, and strings were of animal gut. Laminated wood construction yielded more strength in racquets used through most of the 20th century until first metal and then composites of carbon graphite, ceramics, and lighter metals such as titanium were introduced. Nowadays they use synthetic strings. For clothing usually male players wear collared polos, shorts and tennis shoes. Women also wear short- sleeved polos and tennis-skirts. Sometimes they might use tennis dresses or just simple shorts. Players often use sweat bands on their wrists to keep their hands dry as well. Although the
päritoluga pigiliike ja erinevaid valmistamismeetodeid. Igal neist on omad eelised ja puudused, kuid eelistatakse ikkagi protsesse, mis võimaldavad kiiremini soovitud tulemini jõuda. Selleks, et tootmine oleks kiirem ja tõhusam, on välja töötatud erinevaid võimalusi süsinikkiudude valmistamiseks pigist, millest mõningaid ka selles referaadis tutvustasin. Kasutatud kirjandus: 1. Chung, D. L. 1994. Carbon Fibers made from Pitch rmt: Carbon Fiber Composites, pp. 14-23 2. Arensburger, D. 2005. Boor-, ränikarbiid- ja süsinikkiud rmt: Komposiitmaterjalid, lk. 34-36
expressed in inch/inch or in percent.) 42,000 psi). Any further stress 1, is too small to be considered any The behavior of the two kinds of car- increase results in a disproportionally further.) This "elastic limit" is a very bon composite (HM, HT), of Kevlar 49 large increase in strain. Aluminum important point. All structural parts and of the two glass composites begins to "yield" - an experience of an aircraft (or the kitchen table, or (S2,E), is nicely "straight", meaning familiar to all homebuilders, by the the chair, or the children's swing, or that the elongation, or strain, way - with large strain increases for the bridge, or. . .) must be designed increases in proportion with the stress relatively small stress increases. well under this limit. No structural
It was described as Burmilla x Scottish Fold with large protuberant eyes, short ears and very relaxed nature due its excellent vision. The photo was that of a Brown Burmilla which was been edited to give the cat larger eyes, narrower chin and short ears (the original ear tip had been photographically enlarged and grafted back onto the face). The face was then grafted back onto the image of the cat's body. One giveaway was that the facial area had a "floating effect", which is common in photo-composites. A Scottish Fold would have given folded not shortened ears. In addition, the partial-dominant "macro- retinal" gene mentioned in the text is fictional (and it should have been a macropthalmia gene since the retina is the back of the inside of the eye). BOBTAILED AND CURLY TAILED CATS Copyright 2002 - 2013, S Hartwell THE TAIL The normal tail has 21 - 23 vertebrae on average with the normal range being 18 - 28 vertebrae
annaabi.ee 
