Termilise töötlemise mõju ultraheli levimise kiirusele sanglepa ja halli lepa puidus
Laen...
Kuupäev
2020
Kättesaadavus
08.09.2020
Autorid
Ajakirja pealkiri
Ajakirja ISSN
Köite pealkiri
Kirjastaja
Eesti Maaülikool
Abstrakt
Puitu termiliselt modifitseerides on võimalik teatud puidu omadusi paremaks muuta. Küll
aga on keeruline puidu füüsikalisi omadusi mõõta ilma puitu mehaaniliselt vigastamata.
Ultraheli mõõtmise käigus on võimalik puidu omadusi uurida ilma puitu kahjustamata.
Töö eesmärgiks oli uurida, kui palju mõjutab termilise töötluse aste ultraheli levimise
kiirust kõigis kolmes puidu põhisuunas.
Töös kasutatud sanglepa puitmaterjal varuti Järvselja Õppe- ja Katsemetskonnast ja halli
lepa puit RMK Tartumaa metskonnast.
Termilise töötluse käigus töödeldi kummagi puuliigi katsekehasid kümne erineva
töötlusastmega. Kasutatud temperatuurid varieerusid 160–186 kraadini ning töötluse kestus
60-180 minutini. Võrdluseks on ka mõlema puuliigi kohta naturaalsed termiliselt
töötlemata katsekehad.
By thermally modifying wood, it is possible to improve certain properties of wood. However, it is difficult to measure physical properties of wood without mechanically damaging the wood. With ultrasound measuring, it is possible to measure the properties of wood without damaging it. The aim of this study was to investigate how much the level of thermal treatment affects the ultrasonic propagation in all three main directions in wood. The common alder wood used in this study was collected from RMK Tartu Country forest district and the grey alder wood used in the study was collected form Järvselja Study- and Experimental Forest district. During the thermal treatment, the test specimens of both tree species were treated with ten different level of treatment. The temperature used in treatment varied from 160 to 186 degrees and the duration of treatment varied from 60 to 180 minutes. For comparison, untreated natural specimens were also used.
By thermally modifying wood, it is possible to improve certain properties of wood. However, it is difficult to measure physical properties of wood without mechanically damaging the wood. With ultrasound measuring, it is possible to measure the properties of wood without damaging it. The aim of this study was to investigate how much the level of thermal treatment affects the ultrasonic propagation in all three main directions in wood. The common alder wood used in this study was collected from RMK Tartu Country forest district and the grey alder wood used in the study was collected form Järvselja Study- and Experimental Forest district. During the thermal treatment, the test specimens of both tree species were treated with ten different level of treatment. The temperature used in treatment varied from 160 to 186 degrees and the duration of treatment varied from 60 to 180 minutes. For comparison, untreated natural specimens were also used.
Kirjeldus
Bakalaureusetöö
Metsanduse õppekaval
Märksõnad
bakalaureusetööd, termotöötlemine, sanglepp, hall lepp