Eksploatacijsko ispitivanje trošenja nitriranog lančanika bicikla

master's thesis

• Title (english): Exploitation testing of wear on a nitrided bicycle chainwheel
• Author: Bartol Marinović
• Mentor: Darko Landek (mentor)
• Granter: University of Zagreb; Faculty of Mechanical Engineering and Naval Architecture; Zagreb
• Defense date and country: 2019-07-11, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Mechanical Engineering; General Mechanical Engineering (Construction)

Abstract

Tema istraživanja obuhvaća detaljan opis postupka plazmom potpomognutog nitriranja i nitriokarburiranja u solnoj kupci TENIFER te njihovu primjenu u svrhu poboljšavanja mehaničkih i triboloških svojstava lančanika bicikla. Rad opisuje povijesni razvoj i podjelu bicikala ovisno o njihovoj namjeni te konstrukciju bicikla uzimajući u obzir kritične dijelove sklopa. Naglasak će biti stavljen na tribološka i mehanička svojstva prijenosa bicikla, odnosno tribosustav „lanac-lančanik“. Kao predmet eksperimentalnog dijela rada izdvojen je lančanik s 22 zuba koji predstavlja najlakši prijenosni omjer pogonskog sklopa bicikla. Na dva takva lančanika provedena je toplinska obrada postupkom nitriranja u plazmi te nitriranja u solnoj kupci TENIFER na još jednom identičnom lančaniku. Tri obrađena lančanika uspoređena su s četvrtim u neobrađenom stanju nakon eksploatacijskog trošenja u identičnim uvjetima. Na svim lančanicima provedena su mjerenja mase, ravnosti i dimenzija profila ozubljenja prije i nakon obrade te nakon eksploatacijskog trošenja. Po završetku eksploatacijskog trošenja provedena su metalografska ispitivanja zone spojeva, difuzijske zone i jezgre lančanika nitriranog u plazmi i lančanika nitriranog TENIFER postupkom. Usporedbom dobivenih rezultata dolazi se do zaključka da je nitriranje u plazmi prikladniji postupak toplinske obrade za povećanje otpornosti trošenja lančanika bicikla od nitriranja u solnoj kupci.

Abstract (english)

The following study covers a detailed description of the plasma enhanced nitrating process and salt bath nitrocarburising TENIFER process as well as their use as a means to improve mechanical and tribological features of a bicycle chainring. The study deals with the historical development of the bicycle and bicycle types according to their purpose, taking into consideration critical components of a bicycle. The stress will be put on the tribological and mechanical features of a drivetrain, i.e. chainring-chain tribological system. The main focus of the experimental part of this study is a 22-tooth chainring which reprisents the low range gear ratio on a bicycle. Two of such chainrings have undergone a heat treatment as a part of a plasma enhanced nitrating process and one has undergone a salt bath nitrocarburising TENIFER process. The three of the processed chainrings were then directly compared to the fourth, which has not undergone a process of any sort, but has undergone exploitation wear test in similar conditions as the previous three chainrings. Afterwards, the four chainrings have undergone measurings of weight, flatness, and the dimensions of the profiles of the teeth before and after the exploitation wear test. Moreover, metallographic examinations of compound layer and diffusion zones have been conducted. By comparing these results, we have come to a conslusion that the plasma enhanced nitrating process is a better heat treatment process for enhancing wear resistance of a bicycle chainring as opposed to salt bath nitrocarburising TENIFER process.

• Keywords: plazma potpomognuto nitriranje; proces nitrokarburiranja; TENIFER; lančanik; bicikl
• Keywords (english): plasma enhanced nitrating; nitrocarburising process; TENIFER; chainring; bicycle
• Language: croatian
• URN:NBN: urn:nbn:hr:235:687122
• 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: 2019-07-08 09:00:52