Utjecaj usmjerenosti strukture na tvrdoću i abrazijsku otpornost drva hrasta kitnjaka

master's thesis

• Title (english): Influence of structure orientation on hardness and abrasion resistance of the sessile oak wood
• Author: Kata Soldo
• Mentor: Vera Rede (mentor)
• Granter: University of Zagreb; Faculty of Mechanical Engineering and Naval Architecture; Zagreb
• Defense date and country: 2021-07-14, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Mechanical Engineering; Precision Mechanical Engineering

Abstract

Osnovni zadatak ovog rada bio je odrediti kako usmjerenost strukture utječe na tvrdoću i otpornost na abrazijsko trošenje drva hrasta kitnjaka (lat. Quercus petraea). Ispitivanje abrazijske otpornosti provedeno je metodom „suhi pijesak – gumeni kotač“, a mjerenje tvrdoće metodom po Brinellu. U radu je utvrđeno da postoji korelacija između usmjerenosti strukture i odnosa tvrdoće i gubitka volumena pri abraziji. Kod manjih kutova (do 52°) s povećanjem tvrdoće smanjuje se gubitak volumena, a kod većih kutova s povećanjem tvrdoće povećava se gubitak volumena. Udio vlage i gustoća ovise o poziciji uzoraka u poprečnom presjeku debla. Također je utvrđeno da se povećanjem gustoće uzoraka povećava tvrdoća, a smanjuje gubitak volumena pri abraziji. Vrijednosti i rasipanja rezultata za gustoću, gubitak volumena pri abraziji i tvrdoću ponašaju se po zakonu Weibullove razdiobe, kojom su statistički analizirani.

Abstract (english)

The main purpose of this thesis was to determine how the orientation of the structure affects the hardness and abrasion resistance of sessile oak wood (lat. Quercus petraea). The abrasion resistance test was conducted by the "dry sand - rubber wheel" method, and the hardness measurement by the Brinell method. In the thesis is determined that there is a correlation between the orientation of the structure and the relationship between hardness and volume loss during abrasion. At smaller angles (up to 52°) the volume loss decreases with increasing hardness, and at larger angles with increasing hardness the volume loss increases. The moisture content and density depend on the position of the samples in the cross section of the trunk. It has also been found that increasing the density of the specimens increases the hardness and reduces the volume loss on abrasion. The values and scatter of the results for density, volume loss on abrasion and hardness are distributed by the Weibull's distribution law, by which they are statistically analyzed.

• Keywords: abrazijsko trošenje; tvrdoća; gustoća; hrast kitnjak
• Keywords (english): abrasion wear; hardness; density; sessile oak
• Language: croatian
• URN:NBN: urn:nbn:hr:235:197334
• Study programme: Title: Mechanical Engineering; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra inženjer/inženjerka strojarstva (magistar/magistra inženjer/inženjerka strojarstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2021-07-12 11:55:49